With all of the attention grabbed by Pluto in recent months, it’s easy to lose sight of just how much exploration is actually taking place across the solar system.

Lately, most of the news has come from NASA’s New Horizons flyby of Pluto, Cassini’s ongoing investigation of Saturn and its enigmatic moons and the Curiosity rover’s geologic quest on the slopes of Mount Sharp on Mars.

The European Space Agency’s Rosetta spacecraft and Philae lander are carrying us on a roller coaster ride around the sun on Comet Churyumov-Gerasimenko.

A small fleet of solar observatories like NASA’s Solar Dynamics Observatory and the ESA’s SOHO keep an unblinking eye on our tumultuous sun.

In fact, there are dozens of robotic spacecraft spread across the solar system, quietly exploring objects and regions from Earth’s moon all the way out to the frontier of interstellar space, three times more distant than Pluto.

Below are three current space expeditions that may yield results as soon as next year.

Asteroid Expedition: Orbit, Land, Rove, Return!

Have you heard of Hayabusa 2? Launched by Japan last December, this spacecraft is currently en route to the near-Earth object 1999 JU3, where it will arrive in 2018.

The spacecraft will spend about 18 months examining this half-mile-wide asteroid and employing a variety of exploration technologies, including deploying a lander and a rover to its surface, creating and exploring an artificial crater with an impactor projectile and the lander, and ultimately returning samples of the asteroid to Earth.

Sounds like a novel mission, but in fact this isn’t the first to bring pieces of an asteroid home to us; Hayabusa 2’s predecessor, Hayabusa (1), collected and returned samples of the asteroid Itokawa in 2010.

And 1999 JU3 is a “C” type asteroid, a carbonaceous object composed of clay and silicate rocks. Though C-type asteroids are the most common (75% of asteroids are of this type), they are among the oldest objects in the solar system. They are also thought to contain organic material and water (in hydrated rock).

These two factors—their origin in the earliest times of the solar system’s formation, and the water and organic molecules they may contain—can provide clues of how a planet like the Earth formed, in particular in relation to Earth’s oceans and the emergence of life.

Recycled Robots

Did you know that the green “reuse-recycle” ethic is occasionally employed with space missions? This is the case with ARTEMIS—a mission you may not have heard of even during its first incarnation.

ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon’s Interaction with the Sun) consists of two spacecraft that were originally members of another multi-probe mission called THEMIS.

The original five THEMIS spacecraft orbited the Earth starting in 2007 studying its aurora, but two of the solar-powered probes were in danger of losing power due to spending too much time in Earth’s shadow.

Instead of falling into dark silence, these two were sent on a new mission to the Moon, and renamed ARTEMIS-P1 and ARTEMIS-P2.

In 2010 the two repurposed spacecraft arrived at their initial destinations, the L1 and L2 Earth-Moon “Lagrange” points, where a balancing act between the Earth’s and the Moon’s gravity creates semi-stable “pockets” where spacecraft can dwell. L1 resides between the Earth and Moon, and L2 on the far side of the Moon.

These Lagrange points reside outside of Earth’s magnetic field, and so were excellent vantage points for the ARTEMIS spacecraft to study the properties of the solar wind and how it interacts with the Earth’s long magnetic tail and the Moon’s weak magnetism.

In 2011, both spacecraft were moved from the Lagrange points into close lunar orbits, and began a new phase of their repurposed mission to study the Moon more closely, including the structure of its core and its detailed surface magnetism. The ARTEMIS mission is still in progress.

Juno to Jupiter

NASA’s Juno mission also hasn’t been on people’s radar, but not because its mission isn’t large. In fact, its mission objective is the biggest thing in the solar system, the planet Jupiter, where it will arrive in July of 2016 and enter a first-ever polar orbit of the gas giant.

By investigating Jupiter’s polar regions, the Juno spacecraft will make detailed measurements of Jupiter’s powerful magnetic field where it emerges from within the planet, the structure of its atmosphere, and its gravitational field, giving scientists a glimpse of what’s going on deep within Jupiter’s thick gaseous layers and down to its core.

Probing Jupiter’s interior structure may give us insights into how Jupiter formed, and by extension the history of the formation of other planets in the solar system.

Five decades ago the first robotic probe to reach any place in the solar system beyond the Earth-Moon system, Mariner 4, flew by Mars, capturing and transmitting back to Earth less than two dozen images.

Today, the playing field of solar system exploration is crowded.

We’re in for a treat as spacecraft gather information and help us better understand the world in which we live.

On August 17, NASA’s Cassini spacecraft made its final close flyby of Dione, one of Saturn’s fascinating moons, sending us the highest-resolution pictures of its surface to date.

And though this isn’t the last flyby of a moon in store for Cassini, the event marks the beginning of this flagship mission’s end game.

On this fifth and final flyby of Dione, Cassini passed within 295 miles of the moon’s surface — a bit higher than the International Space Station orbits the Earth (keeping in mind, though, that Dione is only about 660 miles across).

Though Cassini accomplished some exquisite photography, the primary objective of this pass was to probe Dione’s gravity, magnetic field, and the plasma environment around it.

Analysis of these data will allow scientists to probe the moon’s interior structure. Similar measurements of two of Saturn’s other moons, Titan and Enceladus, were responsible for the discovery of liquid seas deep beneath their crusts.

It’s too early to tell what this flyby will reveal about the realm beneath Dione’s surface, but if there’s one thing we have learned from Cassini about the moons of Saturn, they tend to be full of surprises.

In the months ahead, Cassini will buzz other Saturnian moons, including three passages of Enceladus, one at a distance of only 30 miles from its surface.

This moon-raking graze will send Cassini deeper than ever before into Enceladus’ plumes of water vapor, which spew from under the moon’s crust. That encounter could reveal more eye-opening clues about the moon’s subsurface geyser chambers, sea, and possible hydrothermal vent activity at the sea floor — all of which have been detected previously.

Cassini’s 11-plus-year mission has been a stunning success in terms of its exploration and close scrutiny of Saturn, its system of ice and dust particle rings, and its entourage of moons.

Early in the mission, in 2005, Cassini launched the European Space Agency’s (ESA) Huygens probe onto the surface of Saturn’s largest moon, Titan, making it the only solid surface in the outer solar system on which we’ve landed a spacecraft.

Over the last decade Cassini, and the Huygens probe, have greatly illuminated the Saturn system — but the mission did not begin without some controversy.

The 1997 launch of this spacecraft, which carries 73 pounds of plutonium within three radioisotope thermoelectric generators (RTGs), was met with strong opposition. Protesters were concerned with the possibility that a launch accident could spread the radioactive material into the Earth’s environment and pose health risks to human and animal populations.

Exploration of the outer solar system, particularly as far from the sun as Saturn, requires a source of power other than sunlight, since sunlight at that distance is too weak for solar panels to be a practical alternative. Heat from the radioactive decay of substances like plutonium offers a steady and long-lasting supply of energy with which to generate electricity.

The New Horizons spacecraft, which recently made its close flyby of Pluto, is powered by one of the Cassini mission’s spare plutonium-238 RTGs.

After next December, Cassini will make only a small number of distant flybys of Saturn’s larger icy moons, and after that a series of long-range encounters with some of Saturn’s tiny, irregular moons, which we haven’t seen in any great detail so far.

Then in 2017, Cassini will enter what is being called its grand finale, steered into an inclined orbit that will send it repeatedly between Saturn and its innermost rings, a region that no spacecraft has ever before explored.

With the mission refocused exclusively on close-up investigation of Saturn and its rings, this daring and somewhat risky maneuver will deliver details about the gas giant planet as never before. Cassini will probe the interior of Saturn through its magnetic field, take extreme high-resolution images of its cloud systems, and obtain much better measurements of the mass of its ring system, which could give scientists great insight into its origin.

Then, at the conclusion of Cassini’s mission, the spacecraft will be sent into a fiery burn-up in Saturn’s atmosphere, eliminating any chance of its plutonium fuel from ever contaminating one of Saturn’s moons—particularly the water-bearing Enceladus, and cold, liquid-methane drenched Titan. (Maybe this self-sacrifice to protect any possible life on the moons of Saturn will make up a little for earlier concerns to life on Earth.)

In the meantime, our adventure in the Saturn system isn’t over yet, and we can expect more amazing revelations over the next year or two.

Data from NASA’s Mars Reconnaissance Orbiter provides “the strongest evidence yet that liquid water flows intermittently on present-day Mars,” NASA announced on Monday.

You can watch the video replay of the announcement here:

Photos from the Mars orbiter show dark streaks flowing down Martian slopes. The streaks appear in sunny spots or when the weather is warm, and they fade when the temperature drops.

Water was suspected to be involved, but now scientists have confirmed its presence. The new analysis, published in Nature Geoscience, shows salts mixed with water when the streaks are darkest. The water disappears when the streaks lighten.

The following animation “simulates a fly-around look at one of the places on Mars where dark streaks advance down slopes during warm seasons, possibly involving liquid water,” NASA says. “This site is within Hale Crater. The streaks are roughly the length of a football field.”

“We don’t know where the water actually comes from. That’s the next puzzle,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program, at this morning’s announcement.

“We haven’t seen rain on Mars because the surface pressure is way too low,” said John Grunsfeld, a physicist and former NASA astronaut. “But we have seen snow … so there is a water cycle.”

More on the possible source of the water from Popular Mechanics:

Some of the hypotheses include an underground aquifer, accumulations of humidity, or possible seasonal melting, though there is a counter for each. (Like an aquifer extending into mountainous regions, possible lack of sufficient humidity, or lack of regional surface ices, respectively.) The team also is working under the idea that it could be a mix of all of these.

An abundance of evidence exists that surface water flowed on Mars billions of years ago.  In 2008, NASA scientists confirmed the existence of frozen water on the planet. In 2010,  the space agency announced it had found evidence of subsurface water. In 2013, the Curiosity rover found water in Mars’ soil.

As to the significance of the most recent discovery, Jim Green, director of planetary science at NASA Headquarters, said, “This is tremendously exciting. … Everywhere we find water, we find life.”

Alfred McEwen, principal investigator for the High Resolution Imaging Science Experiment (HiRISE) at the University of Arizona in Tucson, said it’s “very likely” that there is microbial life on the subsurface of Mars.

Here is NASA’s complete press release on the latest discovery:

New findings from NASA’s Mars Reconnaissance Orbiter (MRO) provide the strongest evidence yet that liquid water flows intermittently on present-day Mars.

Using an imaging spectrometer on MRO, researchers detected signatures of hydrated minerals on slopes where mysterious streaks are seen on the Red Planet. These darkish streaks appear to ebb and flow over time. They darken and appear to flow down steep slopes during warm seasons, and then fade in cooler seasons. They appear in several locations on Mars when temperatures are above minus 10 degrees Fahrenheit (minus 23 Celsius), and disappear at colder times.

“Our quest on Mars has been to ‘follow the water,’ in our search for life in the universe, and now we have convincing science that validates what we’ve long suspected,” said John Grunsfeld, astronaut and associate administrator of NASA’s Science Mission Directorate in Washington. “This is a significant development, as it appears to confirm that water — albeit briny — is flowing today on the surface of Mars.”

These downhill flows, known as recurring slope lineae (RSL), often have been described as possibly related to liquid water. The new findings of hydrated salts on the slopes point to what that relationship may be to these dark features. The hydrated salts would lower the freezing point of a liquid brine, just as salt on roads here on Earth causes ice and snow to melt more rapidly. Scientists say it’s likely a shallow subsurface flow, with enough water wicking to the surface to explain the darkening.

“We found the hydrated salts only when the seasonal features were widest, which suggests that either the dark streaks themselves or a process that forms them is the source of the hydration. In either case, the detection of hydrated salts on these slopes means that water plays a vital role in the formation of these streaks,” said Lujendra Ojha of the Georgia Institute of Technology (Georgia Tech) in Atlanta, lead author of a report on these findings published Sept. 28 by Nature Geoscience.

Ojha first noticed these puzzling features as a University of Arizona undergraduate student in 2010, using images from the MRO’s High Resolution Imaging Science Experiment (HiRISE). HiRISE observations now have documented RSL at dozens of sites on Mars. The new study pairs HiRISE observations with mineral mapping by MRO’s Compact Reconnaissance Imaging Spectrometer for Mars (CRISM).

The spectrometer observations show signatures of hydrated salts at multiple RSL locations, but only when the dark features were relatively wide. When the researchers looked at the same locations and RSL weren’t as extensive, they detected no hydrated salt.

Ojha and his co-authors interpret the spectral signatures as caused by hydrated minerals called perchlorates. The hydrated salts most consistent with the chemical signatures are likely a mixture of magnesium perchlorate, magnesium chlorate and sodium perchlorate. Some perchlorates have been shown to keep liquids from freezing even when conditions are as cold as minus 94 degrees Fahrenheit (minus 70 Celsius). On Earth, naturally produced perchlorates are concentrated in deserts, and some types of perchlorates can be used as rocket propellant.

Perchlorates have previously been seen on Mars. NASA’s Phoenix lander and Curiosity rover both found them in the planet’s soil, and some scientists believe that the Viking missions in the 1970s measured signatures of these salts. However, this study of RSL detected perchlorates, now in hydrated form, in different areas than those explored by the landers. This also is the first time perchlorates have been identified from orbit.

MRO has been examining Mars since 2006 with its six science instruments.

“The ability of MRO to observe for multiple Mars years with a payload able to see the fine detail of these features has enabled findings such as these: first identifying the puzzling seasonal streaks and now making a big step towards explaining what they are,” said Rich Zurek, MRO project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California.

For Ojha, the new findings are more proof that the mysterious lines he first saw darkening Martian slopes five years ago are, indeed, present-day water.

“When most people talk about water on Mars, they’re usually talking about ancient water or frozen water,” he said. “Now we know there’s more to the story. This is the first spectral detection that unambiguously supports our liquid water-formation hypotheses for RSL.”

The discovery is the latest of many breakthroughs by NASA’s Mars missions.

“It took multiple spacecraft over several years to solve this mystery, and now we know there is liquid water on the surface of this cold, desert planet,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program at the agency’s headquarters in Washington. “It seems that the more we study Mars, the more we learn how life could be supported and where there are resources to support life in the future.”

There are eight co-authors of the Nature Geoscience paper, including Mary Beth Wilhelm at NASA’s Ames Research Center in Moffett Field, California and Georgia Tech; CRISM Principal Investigator Scott Murchie of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland; and HiRISE Principal Investigator Alfred McEwen of the University of Arizona Lunar and Planetary Laboratory in Tucson, Arizona. Others are at Georgia Tech, the Southwest Research Institute in Boulder, Colorado, and Laboratoire de Planétologie et Géodynamique in Nantes, France.

The agency’s Jet Propulsion Laboratory in Pasadena, California, a division of the California Institute of Technology, manages the Mars Reconnaissance Orbiter Project for NASA’s Science Mission Directorate, Washington. Lockheed Martin built the orbiter and collaborates with JPL to operate it.

Jon Brooks, NPR and Associated Press contributed to this post.

As soon as NASA announced finding evidence of liquid water on Mars last month, speculation erupted that scientists may be able to answer the age-old question: Is there life on Mars?

Technically, we already know the answer.

“The answer is, ‘Yes,’ and it’s probably our own life,” says David J. Smith, a scientist at NASA’s Ames Research Center in Mountain View.

Here on Earth, bacteria cover every surface we touch. And despite efforts to keep spacecraft as clean as possible, bacteria have likely hitchhiked all the way to Mars on NASA missions. Bacterial contamination was detected on the rovers that have driven across the red Martian desert.

Listen to the story:

These microbial travelers pose a big problem.

If a robot or astronaut drills into the Mars surface, testing for life, the Earth bacteria could get in the way, contaminating those tests.

“So we want to make sure that it is, in fact, Martian life that we find, potentially, and not just Earth contamination,” Smith says. “That would be a major bummer.”

Extreme Microbes

The Mars environment has a kind of biohazard safeguard already built in: it’s not a comfortable environment for most Earth bacteria to live in.

“It’s just not a nice place,” Smith says. “It’s extremely dry. Very cold.”

And with little atmosphere surrounding it, the surface of the planet is blasted with ultraviolet radiation. Most Earth microbes couldn’t hack it in those conditions. But Smith studies one that may have what it takes.

“The bacteria is called Bacillus pumilus SAFR-032,” he says. “That’s a mouthful.”

To endure extreme conditions, it forms a spore, essentially hunkering down in a biological fortress.

“In a sense, it’s like hibernation for bacteria,” Smith says. When it finds food or water again, it wakes back up.

This super-tough strain was found on a NASA spacecraft as it was being built inside a clean room, a place that’s meant to be mostly bacteria-free.

But how would the microbe fare if it got out on the Martian surface? Studying it there isn’t really possible. So, Smith is doing the next best thing.

Bacteria Take Flight

Twenty-three miles above Earth, at the very top of our atmosphere, it’s a lot like Mars: cold, dry and bombarded with UV radiation from the sun.

In early October, Smith and his colleagues launched millions of Bacillus pumilus bacteria to that altitude on a special ride.

A massive helium balloon, almost 1,000 feet tall, carried the bacteria in a miniature laboratory underneath it. The project is called E-MIST (Exposing Microorganisms in the Stratosphere).

High above the Earth, the bacteria hung out for eight hours in the thin air and intense sunlight—conditions a lot like Mars.

Then, the balloon popped, sending them back to Earth on a parachute.

The bacterial samples were then picked up in Texas. Smith will be looking to see if they’re still alive and growing.

“It wouldn’t surprise me,” he says. “The adaptability and persistence of bacteria is consistently impressive.”

Planetary Protector

“The more we learn about Earth life, the more we realize it’s actually likely that Earth organisms could live on Mars,” says Catharine Conley, NASA’s Planetary Protection Officer. Her job, in essence, is protecting Mars from us.

Just as soon the liquid water announcement was made, NASA’s planetary protection policies were called into play, something that’s governed by international treaty.

NASA’s Curiosity rover is currently on Mars, driving around not far from the discovery site. But if the car-sized rover went to investigate, it would bring along Earth bacteria.

“It’s possible that there’s some kind sub-surface aquifer on Mars that we didn’t expect,” Conley says. “And so it would be equally foolish to go and introduce Earth organisms.”

On NASA’s 1975 Viking missions to Mars, the spacecraft were sterilized to kill off bacterial life.

“The spacecraft were designed to tolerate heat treatment – being baked above the boiling point of water for several days,” Conley says. “It didn’t quite kill off all of the organisms on the surface of the spacecraft, but it killed off the majority of them.”

But heat treatment is extremely expensive. So, areas of Mars that were seen as more hospitable to life were protected as “special regions.” Missions landing outside those regions could have higher levels of microbial contamination.

“This was a compromise,” says Conley. “Because as we keep exploring Mars, we discover that more of Mars is actually ‘special.’ And so we actually should be more careful than we have been being.”

Conley adds that understanding the resilience of Earth microbes will help inform NASA’s efforts to come. It may be that allowing spacecraft to “cure” on Mars, sitting in the intense UV light long enough, would be adequate to kill off even the hardiest Earth bacteria.

“This is the first time that humans as a species have had the chance to really explore carefully,” she says.

Humans don’t have a great track record of that. In the name of exploration, we’ve spread invasive species and diseases around our own planet. The hope is not to repeat that on other planets.

“We haven’t made any mistakes yet,” Conley says. “I really hope that we won’t do it while I’m in this job.”

Protecting Mars will only get tougher once humans start walking on the red planet. NASA is planning to make that happen in about twenty years.

Last week, NASA’s Mars Atmospheric and Volatile Evolution (MAVEN) mission identified the smoking gun in the whodunit mystery of what happened to Mars’ once much warmer, thicker, and more Earth-like atmosphere.

As some suspected, it has slowly been blown into space by energetic particles of the solar wind. Turns out the sun did it! My money was on the butler….

Picturing a Warmer, Wetter Mars

In the saga of our exploration of Mars, which has unfolded over the past five decades since the first robotic probe sent back images taken at close range, our understanding of Mars has improved dramatically.

Early missions reported a dry, cold desert planet with an atmosphere a hundredth as thick as Earth’s, composed mostly of carbon dioxide.

More recently, missions in orbit and on the ground have churned up a preponderance of geological evidence that long ago liquid water flowed across Mars’ surface, filling large lakes and even shallow seas—an environment that may have been suitable to sustain life.

The very presence of liquid water in Mars’ past tells us that its atmosphere had to be much more substantial at one time–thicker, warmer.

So a big question has been, what happened to the atmosphere? 

Understanding what is responsible for the drastic difference between the cold dry Mars we see today and the warm and wet Mars of the distant past is key to answering important questions not only about Mars, but our home planet as well.

Might Earth someday fall victim to a similar crime? Is there a serial killer of planetary atmospheres on the loose, and should people on Earth start stock-piling tanks of air and water against the prospects of a Martian-esque future?

Don’t panic.

MAVEN was the first spacecraft ever sent to explore the uppermost regions of Mars’ atmosphere, where it comes into contact with the environment of the solar wind. It was believed that the answer to the mystery might be found in this region, but on-site forensic work was needed to prove it.

The solar wind is a continuous flow of high-speed, electrically charged particles (plasma) and magnetic fields exuded by the sun.

Blowing by with an average speed of about a million miles an hour, the solar wind affects the entire solar system, including the Earth. All of the objects in the solar system, even far beyond Pluto, are within this outflowing “bubble” of plasma.

How Does the Solar Wind Affect Us Here on Earth?

Here at home, we can see the effects of exceptional solar wind activity: dazzling auroras around Earth’s poles, and “geomagnetic storms” (fluctuations in Earth’s magnetic field) that on rare occasion have knocked out power grids.

These effects, however, are not the result of the solar wind hammering away at our upper atmosphere, but by its interaction with Earth’s more extensive magnetic field. Earth’s atmosphere, for the most part, is safely tucked away within our planet’s great magnetic deflector shield.

Mars, however, does not enjoy the same protection. Mars, at present, has no structured global magnetic field as Earth does—the kind with north and south poles and an enveloping donut shape, like a textbook bar magnet. With respect to the solar wind’s abrasive action, Mars’ deflectors are down.

Scientists had hypothesized, and now MAVEN has verified, that the energetic ions of the solar wind coming into direct contact with Martian atmospheric atoms result in those atoms being kicked off into space, thus slowly leaking away at Mars’ atmosphere.

How Bad Is the Leak in Mars’ Atmosphere?

MAVEN has detected the amount of atmospheric gases escaping from Mars: around 100 grams per second.

About three-quarters of the loss occurs through a long “tail” extending away from the sun’s direction, and another quarter through a plume spewing off of Mars’ polar region.

MAVEN has also found that the loss rate rises dramatically when solar wind activity increases, such as during solar storms.

With this insight, we can now envision how Mars probably lost a major part of its atmosphere in the solar system’s younger days, billions of years ago, when the sun was more active and the solar wind more abrasive.

Though our understanding of exactly how Mars lost its water-supporting atmosphere won’t bring it back, it may help us better understand what Mars is all about today, including how we might go about looking for any remnants of its global paleoclimate.

Recently, NASA’s Mars Reconnaissance Orbiter confirmed the presence of trickles of briny liquid water seeping in certain spots on Mars today—a discovery that has scientists interested in finding signs of life on Mars very excited.

In what may not be unlike a space-geek’s version of American Idol, NASA has judged five proposals for interplanetary missions worthy of moving onto a final round of competition for selection under its Discover program.

While it is likely that only one contender will win the prize of being fully funded, each represents exciting potential for exploration, including probing the atmosphere and surface of Venus, exploring distant and ancient asteroids, and searching for objects that sometimes come perilously close to the Earth.

NASA’s Discovery program is designed to produce quick-paced and relatively inexpensive missions to explore important questions about our solar system, without the encumbrance involved in time-consuming and expensive “flagship” missions like Curiosity or Cassini.

An example of a highly successful Discovery mission is NASA’s Dawn, which only last March became the first spacecraft to encounter a dwarf planet when it arrived at Ceres, following a year-long exploration of the protoplanet Vesta.

Among the five missions being considered–four of which are led by women–two are focused on Earth’s near neighbor and size-twin, Venus, and three on various aspects of small solar system bodies: asteroids.

Contestant 1: DAVINCI

The Deep Atmospheric Venus Investigation of Noble gases, Chemistry, and Imaging (DAVINCI—yes, NASA really works hard to make its acronyms say something!) would make a gradual, hour-long descent through Venus’ thick atmosphere, studying its composition and other properties along the way. DAVINCI would also attempt to confirm recent exciting evidence that there may be active volcanoes on Venus today.

Contestant 2: VERITAS

Another Venus exploration proposal, the Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy (VERITAS) would make high-resolution image maps of Venus’ surface. So far, we have only seen Venus’ surface through relatively low-resolution radar maps, such as those made by the Magellan spacecraft decades ago, and the few close-up images taken by Soviet landers even earlier.

So much attention has been given to Mars in recent years that Venus seems to have become an afterthought in near-solar-system exploration–but that does not mean Venus is less interesting. Venus’ extremely inhospitable atmospheric pressure and temperature present greater challenges to exploration than Mars, but that is merely a hurdle to technological innovation, and not a barrier to curiosity.

Active volcanoes on Venus? Awesome. There are even thoughts that once, long ago, Venus may have possessed oceans, a possibility that examination of its present-day atmosphere could reveal to us.

The balance of the Discovery mission contestants focus on much more accessible solar system objects: asteroids.

Contestant 3: Lucy

The Lucy mission would send the first-ever spacecraft to explore a distant and special group of space rocks: Jupiter’s Trojan asteroids. Trojan asteroids accumulate in two gravitationally stable “pockets” called “Lagrangian” points, which lead and trail Jupiter in its orbit around the sun. Jupiter’s Trojans number over 6,000, and are believed to have been captured in Jupiter’s L4 and L5 Lagrangian points early in the formation of the solar system. Lucy would be the most distant asteroid encounter mission to date, since the targets of past asteroid missions reside within the Main Asteroid Belt, between the orbits of Mars and Jupiter.

Contestant 4: Psyche

The Psyche mission would send a spacecraft to explore the asteroid Psyche, one of the largest objects in the Main Asteroid Belt. Psyche is the remnant of a protoplanet whose outer layers were blasted away by a collision with another body. Psyche might offer a visiting spacecraft an unobstructed view of parts of the asteroid that originally formed deep within it.

Contestant 5: NEOCam

The final Discovery candidate under consideration is NEOCam, which would focus on detecting and tracking asteroids—and potentially comets—that pass close to Earth’s orbit. NEOCam would be stationed closer to the sun than Earth, near Venus’ orbit, and sweep its infrared gaze around Earth’s entire orbital path. We already know of about 10,000 Near Earth Objects (NEOs), including almost all of the larger ones. But the smaller the NEO, the more easily it evades detection. NEOCam is expected to detect 100,000 or more as yet unknown NEOs, vastly improving our ability to predict possible future collisions with Earth.

So who will become NASA’s next Solar System Discovery Idol?

Who would get your vote? Do Venusian volcanoes strike your fancy, or are you more concerned with space rocks that could punch a hole in Earth’s surface? Or maybe ancient asteroids that tell a story of the early formation of the solar system is what plays on your fascination.

Voting lines are now open! (If only….)

On Monday, NASA started accepting applications for its new class of astronauts. Applying is simple: Just log in to USAjobs.gov, search for “astronaut,” and upload your resume and references. The job description says “Frequent travel may be required.”

It’s a bit more difficult to be picked. In 2013, more than 6,000 people applied to the program. Only eight were selected. That’s an acceptance rate of a little more than one-tenth of 1 percent.

To be an astronaut, you need a degree in a scientific field, vision correctable to 20/20, and you’ve got to stand between 4 feet, 8.5 inches tall and 6 foot 4. (History suggests it also helps to be white and a man, but NASA says it’s trying hard to remedy that.)

Still, there are many possible paths to space. For former astronaut Charlie Bolden, that journey started in middle school.

“I fell in love with a place called the United States Naval Academy in seventh grade when I saw a program on television called Men of Annapolis,” Bolden says.

The men portrayed in the program reminded him of his father and uncles, who had served in WWII. He resolved to attend the academy once he graduated from high school. But there was a problem.

“I grew up in the segregated South,” Bolden says.

The South Carolina congressional delegation refused to give Bolden the required nomination to the school. An Illinois congressman, instead, opened the way to the Naval Academy, and Bolden began his military career. He flew in Vietnam, became a test pilot, and was selected to become an astronaut in 1980. It was the beginning of the space shuttle era.

For Mike Massimino, another former astronaut, it all started with Apollo 11 in the summer of 1969.

“I was 6 years old when Neil Armstrong walked on the moon,” Massimino says. “And I wanted to be an astronaut — dressed up like an astronaut for Halloween, played astronaut in my backyard with my little astronaut, Snoopy.”

But as he grew up, in Franklin Square, N.Y., that dream started to seem “ridiculous,” Massimino says. “I didn’t know anybody that was an astronaut.”

So he went to school to become an engineer. After picking up a degree from Columbia University and four more from MIT, Massimino was accepted to the astronaut corps in 1996.

Maria Banks, a postdoctoral fellow at the Smithsonian Institution’s National Air and Space Museum, is planning to apply to the astronaut corps this year. In college, she studied harp performance, and when she graduated she found a job playing on a cruise ship that traveled all over the world.

“I would take soil samples and rock samples and hide them in my suitcase,” Banks says. “I don’t know why; I just had to do it. Every day I would try to find the most geologically interesting thing I could do — climb a volcano, or hike a desert, hike on glaciers.”

That sent her back to school, where she started a Ph.D. program in geology and planetary science. Among other things, she studied the fingerprints of glaciers on Mars, using data and images from NASA missions.

These three people — a pilot, an engineer, a planetary geologist — came from different backgrounds and different eras, but they all felt the same way about applying.

“I was convinced that I did not stand any chance,” Bolden says.

“I thought there was no way they were going to pick me,” Massimino says.

“I guess I didn’t believe it was … an attainable goal,” Banks says.

But they still applied.

Though the technological side of the application has changed a bit over the years (Bolden wrote his application on a sheet of paper; Banks will visit the USAjobs website), the selection process has remained virtually identical.

Current astronauts and NASA officials sift through the applications — eliminating the obviously unqualified and making piles, based on profession. Physicists are compared with other physicists. Pilots with other pilots. The cream of the crop (100 or so) will be invited to Houston for live interviews and medical screening. Then a small number will be selected to begin about two years of intense astronaut training.

“If you’re not tops at what you’re doing now,” Bolden says, “you’re not going to be selected.”

Bolden was tops. He went on to pilot two shuttle missions and commanded two more. He helped put the Hubble Space Telescope into orbit. In 2009, President Obama appointed him the head of NASA.

It took Massimino a few more tries to get accepted. He first applied in 1989, then again in 1991 and was rejected. In 1994, he made it to the interview round.

“My attitude was just to be myself,” Massimino says. “When you’re trying to realize a life’s dream, you want to speak from the heart.”

He was rejected again.

Finally, in 1996, NASA selected him. He flew on two shuttle missions and helped repair the Hubble. He became the first person to tweet from space. Today he’s a professor at Columbia.

This round will be Banks’ third attempt.

” ‘Just keep trying,’ ” she says. “Those are the words I kept hearing from all of the astronauts I talked with.”

If Banks is accepted, there is some question about what she’ll do. The shuttle program that began with Bolden ended with Massimino in 2011. Since then, NASA has been accused of lacking clear goals. But Bolden says future astronauts have a lot to look forward to.

“They are going to be the trailblazers for our ventures to Mars,” Bolden says.

He says they’ll fly in new spacecraft and return to lunar orbit for the first time since 1972.

“It all sounds fantastic to me,” Banks says. “I would be happy doing just about anything.”

She’s preparing her application. The deadline: Feb. 18, 2016.

Copyright 2015 NPR. To see more, visit http://www.npr.org/.

NASA’s Dawn spacecraft recently made its closest flyby of Ceres, sending back the most detailed views of its surface.

Ceres is the largest object in the Main Asteroid Belt located between the orbits of Mars and Jupiter, and the only dwarf planet closer to the sun than Pluto.

While news from that other dwarf planet encounter of 2015—New Horizons’ epic and brief July flyby of Pluto—has dominated attention in recent months, Dawn has been quietly and persistently scouring Ceres for information.

Extreme Close-Up

On December 10, Dawn captured images of Ceres’ southern hemisphere from an altitude of only 240 miles, its closest encounter to date. From this close orbit, image resolution of Ceres’ surface is about 120 feet per pixel, which is providing scientists with unprecedented details of the tiny fractured and cratered world.

Speaking of fractures and craters, Dawn has revealed a collection of “trough” features, found all over the dwarf planet’s surface. While many of these cracks appear to be associated with impact craters and formed by shattering collisions with meteorites, some appear to be tectonic in nature.

Tectonic stress fractures have been seen on other solar system bodies, including Earth and Mars. These are cracks formed by the contraction of a planet’s surface or by the weight of mountains that build up, whether by volcanic eruption or tectonic uplift. Olympus Mons, Mars’ mega-volcano, is an example of this.

Though Ceres is very small—only about 584 miles across, on average—the evidence of internal forces and processes that have broken its crust is tantalizing. A number of small bodies in the solar system have surprised us recently by showing signs of internal activity—Ceres, Pluto, and Saturn’s moon Enceladus, to name three.

Detection of Salt and Clay

Dawn’s other instruments have made observations of Ceres’ chemical makeup that are also intriguing. Earlier in December, the composition of the mysterious “bright spots” was revealed as salt, possibly a type of magnesium sulfate called hexahydrate.

Ceres has also been found to contain ammoniated clays, which suggests that the material it formed from may have originated in the outer solar system where ammonia is abundant.

Whether Ceres formed in the outer solar system and then migrated to its present location in the Main Asteroid Belt, or the materials it coalesced from originated out there, is not known, but either way the finding offers fascinating insights into the solar system’s past.

Ceres Is Unique Even Among Dwarf Planets

There are five objects in our solar system classified as dwarf planets (with potentially many more to be added). Four of them—Pluto, Eris, Haumea, and Makemake—are Kuiper Belt Objects, orbiting the sun in a vast belt of icy material extending from beyond the orbit of Neptune.

Among the dwarf planets, Ceres alone resides relatively close to Earth. The rewards of data mined from Pluto and Ceres by New Horizons and Dawn gives us the opportunity to compare these two very different objects, and helps to define the range of variation in properties and surface conditions of dwarf planets.

Dawn’s Advanced Engine Technology

Before arriving at Ceres, Dawn spent a year orbiting the asteroid and protoplanet Vesta, making it the only spacecraft outside of the Earth-Moon system to orbit two different objects. One of the things that enabled Dawn to do this is its cutting-edge electrical ion propulsion system, a highly efficient engine that uses low power, but constant thrust to achieve greater velocity changes than conventional chemical rocket engines.

So what’s in the future for this versatile itinerant robot?

As it turns out, Dawn will remain in orbit as a permanent artificial satellite of Ceres even beyond the duration of its mission, currently schedule to end in June. So, we still have a few months of cool pictures and potentially awesome discoveries to look forward to.

After that, we can shift our anticipation back to New Horizons and its 2019 encounter with Kuiper Belt Object 2014 MU69.

NASA’s Juno spacecraft, bound for Jupiter, passed a milestone on January 13 when it reached a distance of 493 million miles from the sun. That’s about five times the distance between the Earth and sun.

The distance by itself is not the milestone, since numerous spacecraft have ventured far beyond this. The news is that Juno is powered by sunlight, a sparse commodity out in Jupiter’s realm–a sort of “twilight zone” for spacecraft that depend on sunshine!

The 8,000-pound Juno was launched in 2011 on a mission to explore the planet Jupiter in greater detail than previous spacecraft, including the gas giant’s composition, gravity, global magnetic field, and in particular the magnetic field in Jupiter’s polar regions, even probing the properties of its interior.

Before Juno, the record-holder was the European Rosetta spacecraft. Rosetta cruised in hibernation mode through its orbital aphelion (its most distant point from the sun) back in 2012. Later it fell sunward toward its encounter with comet Churyumov-Gerasimenko.

Close to the Sun, Solar-Powered Spacecraft Are the Rule

Within the inner solar system, from the planet Mercury out into the Main Asteroid Belt between the orbits of Mars and Jupiter, robotic exploration is powered almost entirely by photovoltaics—solar cells.

In fact, solar photovoltaic technology was developed for Earth-orbiting satellites. Notable exceptions include short-lived probes dropped to the surface of Venus, which were powered by chemical batteries, and NASA’s Curiosity rover on Mars, which requires the kick of nuclear power to drive its equipment.

Near the sun, sunlight is intense enough to make photovoltaic power practical. At Earth’s distance, sunlight intensity amounts to over a thousand Watts per square meter. A reasonably sized array of solar panels can generate a practical amount of electrical power for a satellite or spacecraft, even though the technology is not 100 percent efficient.

But the farther a spacecraft gets from the sun, the weaker the sunlight becomes, by a factor of the square of the distance. Jupiter is five times farther from the sun than Earth, so sunlight at that distance is weaker by a factor of five-squared, or 25.

Juno’s photovoltaic system consists of three, 30-foot-long panels, which at Earth would generate up to 14,000 Watts of electrical power. At Jupiter where Juno is now approaching, that solar array generates a mere 500 Watts! But, it will be enough to power the efficiently-designed Juno as it probes Jupiter’s interior, atmosphere and magnetic field.

Radioisotope Thermoelectric Generators Run the Show in the Outer Solar System and Beyond

Most missions sent beyond the Main Asteroid Belt are nuclear-powered. NASA’s Galileo, the only other spacecraft to orbit Jupiter, was powered by two radioisotope thermoelectric generators (RTGs) that produced about 570 Watts of electrical power by converting the heat of decaying radioactive material into electricity.

If you’ve seen the movie, “The Martian,” you may recall Matt Damon’s character digging up a device to keep the cab of his rover warm—that was an RTG.

At the time of the Galileo probe, photovoltaic technology wasn’t advanced enough to be a practical power source. The spacecraft would have needed at least 700 square feet of solar panels to function!

Beyond Jupiter, solar-powered spacecraft will likely remain impractical for a long time to come. As sunlight becomes weaker, spacecraft simply need larger collection surfaces to squeeze out energy from sparser photons. At Saturn, where NASA’s Cassini spacecraft has been operating on RTG power for about 12 years now, sunlight is 90 times weaker than at Earth—almost four times weaker than at Jupiter!

The Pioneers, Voyagers, and New Horizons range even farther, in the cold darkness well beyond Neptune’s orbit, where the sunlight trickles in at one-nine-hundredth the strength of Earth-side sunshine.

Juno will arrive at Jupiter this July, to begin the one-year science phase of its mission, after a five-year voyage to get there. At the conclusion of its mission, the spacecraft will be de-orbited to burn up in Jupiter’s atmosphere, following in the fiery footsteps of its predecessor, the Galileo probe.

When it comes to space exploration, there have never been as many exciting reports from space as there are right now.  And we’re not only talking about amazing celestial body discoveries, but also records of distance, time, and the sheer volume of data collected by the spacecraft themselves.

Some of the flashier space headlines have stolen a lot of attention: NASA’s New Horizons flyby of Pluto, the first landing on a comet by Europe’s Rosetta/Philae mission, the confirmation of liquid saltwater on Mars by NASA’s Mars Reconnaissance Orbiter and the list goes on and on.

But in the annals of interplanetary adventure, a few die-hard robots still hold claim to the greatest records of longevity and distance. Some have faded from public memory, having started their voyages so long ago, now as distant in the mind’s eye as they are in space.

Here is a short list of the most prestigious record-holders, and a recap of what their tireless efforts have achieved.

Opportunity

Launched on July 8, 2003, NASA’s Mars Exploration Rover, Opportunity, landed on Mars on January 27, 2004. Now in operation for 12 years and 7 months, Opportunity has driven a total distance of 26.4 miles (as of last August) across a wide basin in Meridiani Planum, investigating the hematite-rich bottom land of what seems to have been a shallow sea long ago.

Cassini

NASA’s Cassini spacecraft was launched October 15, 1997 and arrived at Saturn seven years later on July 1, 2004. Today it is still in operation after more than 18 years in space.

When its mission exploring Saturn and its entourage of moons ends around September 2017, it will have spent almost two decades in space—13 years in the Saturn system alone.

Among its most notable discoveries is liquid water on at least two of Saturn’s moon. Enceladus has water beneath its icy crust and Titan,  Saturn’s largest moon, has liquid water deep underground, as revealed by several close flybys.

Cassini also dropped the European Huygens probe to the surface of Titan in 2005. Together the pair of spacecraft found a frigid world with a thick nitrogen atmosphere, hydrocarbon smog, as well as a global cycle of precipitation, runoff and seas of liquid methane.
Mars Odyssey 2001

Mars has been the venue of many spaceflight firsts and records. It’s the first planet visited by a spacecraft (Mariner 4), the first planet successfully landed upon (USSR’s Mars 3), the first planet visited by a robotic rover (Pathfinder/Sojourner) and the list of firsts doesn’t end there.

It is fitting that the longest functioning spacecraft orbiting another world is a Mars-exploring robot. NASA’s Mars Odyssey, launched on April 7, 2001, has been orbiting Mars since October that same year, over 14 years!

Today, Odyssey serves as a communications relay for surface robots like Opportunity—another longevity and distance record holder of course!

But in its exploration heyday, Odyssey mapped the chemical composition of Mars’ surface, and gave us great insight into the location of water and water-related minerals that have painted the picture of a much more Earth-like world.

Voyager 1

Remember 1977? That’s the year Jimmy Carter took up residence in the White House. It’s also when NASA launched Voyager 1, on September 5, on a mission to cruise by Jupiter and Saturn.

And now, over 38 years later, Voyager 1 is still in operation! Well beyond its last port of call—Saturn in 1980—Voyager 1 has taken the prizes of longest operational space mission and most distant space explorer.

Now at a distance of over 12 billion miles (over three times farther than Pluto), Voyager 1 recently added another prestigious trophy to its shelf of achievements. It is now the first, and so far only, spacecraft to have officially entered interstellar space, beyond the bubble of space dominated by particles from our sun.

The twin Voyager 2, though not as far out as its sibling, is also still in operation, and has its own unique claim to fame, being the only spacecraft to have visited the outer gas giant planets, Uranus and Neptune.

Gone, But Not Completely Forgotten

It’s worth noting a couple other items for the record book, although they’re missions that are no longer in operation.

Years before Voyager, Pioneer 10 launched on March 3, 1972 and headed to Jupiter, becoming the first spacecraft to venture into the outer solar system. Our last contact with Pioneer 10 was on January 23, 2003, after a mission that lasted almost 31 years.

And last, but not least, is the oldest derelict spacecraft of all, Vanguard 1, the fourth artificial satellite sent into space, following Sputniks 1 and 2 and Explorer 1—back in the era when a lot of spacecraft were numbered 1.

Though long defunct, Vanguard still orbits the Earth. Launched on March 17, 1958, it sent its last signal to Earth in May of 1964. Vanguard has been in space for 57 years and 10 months and is expected to remain in orbit until at least 2109.

There are other missions worthy of the record book, and many more vying for a spot on its pages. Here’s the upshot: as difficult as exploring our solar system is, our space programs have achieved remarkable results, and there’s much more adventure to come.

“I have taken a lot of pictures because I’ve been up here for a long time,” NASA astronaut Scott Kelly said during a recent press conference from the International Space Station. “I’ve definitely taken some good ones and some memorable ones.”

When he returns to Earth on Tuesday evening, Kelly will have spent 340 days aboard the ISS. While that’s not quite a year, it’s still a record for an American astronaut, and one of the longest-lasting spaceflights ever.

Kelly is not the only member of his family to visit the station. His twin brother, Mark Kelly, was also an astronaut, and flew multiple shuttle missions to the orbiting outpost. The twins grew up in West Orange, N.J., as the sons of police officers. “We lived a pretty exciting and adventurous life,” Scott says of his childhood.

Scott Kelly takes his images through the windows of the Space Station’s cupola module. It might give the impression that he lives and works with the Earth constantly in view, but that’s not the case. Most of the space station’s rooms are fluorescent-lit boxes. “You don’t get real sunlight,” he says.

His photographs have captured some stunning views of Earth at all times of the day and night. The process of photography has changed his perspective on the planet. “The more I look at Earth, and certain parts of Earth, the more I feel [like] an environmentalist,” Kelly says. “It’s just a blanket of pollution in certain areas. We can fix that if we put our minds to it.”

Photography was one small part of Kelly’s mission. He conducted numerous experiments, some to determine how space was affecting his health, and others to test new technologies, like a dedicated greenhouse for growing plants in zero gravity. NASA hopes the knowledge gained from his extended mission will prepare the space agency for lengthy missions to places like Mars.

Kelly’s photographs have won the astronaut nearly a million followers on Twitter, but he says taking the pictures is only a small part of why he’s there. Kelly believes in space flight, and in humanity’s future beyond the confines of Earth. “The thing I like most about flying in space is not the view,” says Kelly. “The thing I like about it is doing something I feel very, very strongly about.”

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

Here’s a fun fact about long-duration space flight: There’s no shower on board the International Space Station. “It’s kind of like I’ve been in the woods camping for a year,” astronaut Scott Kelly said during a news conference late last week.

Kelly finally gets to come home and wash off the space funk on Tuesday night. He climbed into a Russian Soyuz spacecraft and closed the hatch around 4:40 p.m. ET. His capsule undocked at 8:02 p.m., and he’ll touch down just before 11:30 p.m. on the chilly steppes of Kazakhstan.

While in orbit, Kelly posted hundreds of photos, and we’ve got a selection here.

Kelly’s 340 days in orbit shatters the U.S. record for the longest space journey. Only a handful of cosmonauts have logged more consecutive days in space. Researchers are using the mission, which Kelly conducted with Russian cosmonaut Mikhail Kornienko, to learn more about how prolonged spaceflight affects the body and mind.

The study is unique partly because Kelly has an identical twin: retired astronaut Mark Kelly, who’s stayed back on Earth. Studying the Kelly brothers’ DNA may provide some hints about how spaceflight changes human genetics, says John Charles, the chief scientist of NASA’s human research program.

Check back here later if you need a Super Tuesday break. We’ll have more coverage of the landing.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

You’ve got one chance to watch 2016’s singular total solar eclipse. It’s only visible in Southeast Asia, but good news Area folks: you can watch the event via the Exploratorium’s live feed above.

A total solar eclipse occurs when the Sun is completely blocked as the Moon passes between it and the Earth. The place on Earth where you can see the Sun totally blocked is only 100 miles wide.

The last total solar eclipse happened on March 20, 2015 and the next one is August 21, 2017, which will be visible from the Pacific Northwest to the Southeast.

Until then, find more details about tonight’s eclipse below.

Where can I watch the eclipse?
The video player above!

When can I watch the eclipse?
March 8, 5:00–6:15 p.m. PST

What if I want to watch more?
Today from 4:00-8:00 p.m. PST the player above will stream footage from telescopes on Micronesia capturing the eclipse as it unfolds.
*Note: It’s image-only, without narration

Can I nerd out even more?
Yes! The Exploratorium is offering free admission after 5 p.m. You can watch real-time imagery from telescopes on the coral atoll Woleai and hear scientists talk about NASA’s new multi-satellite endeavor to measure the magnetosphere that connects the Earth and the Sun.

NASA’s InSight mission to Mars is well worth waiting two more years for. InSight will be the first lander equipped to probe beneath the Martian surface, conducting experiments aimed at finding out what goes on inside the planet.

The space agency postponed the launch of InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) earlier this month, after finding a leak that would have endangered one of the lander’s principal instruments, a seismometer.

With a practical launch window for sending the spacecraft to Mars opening and closing this month, NASA decided the leak couldn’t be repaired and tested in time. And since Martian launch windows open only once every two years when Earth and Mars move into favorable positions, NASA will now set its sights on the next one, in May of 2018.

The seismometer (Seismic Experiment for Interior Structure, or SEIS) will monitor internal activity through acoustical waves, not unlike how a doctor listens to a patient’s breathing and heartbeat with a stethoscope. How much activity there is, and where, are clues to Mars’ internal structure and activity.

InSight’s other main instruments are RISE (Rotation and Interior Structure Experiment) and HP3.

RISE will make precision measurements of Mars’ rotation rate, as well as how it wobbles over time, to help us understand the nature of Mars’ core. The physical state of a planet’s core has a strong effect on perturbations in its rotation.

HP3 is a ground-penetrating probe that will measure the temperature at different depths of the Martian topsoil. The data will allow scientists to calculate how fast heat is escaping from Mars. These measurements, combined with data from the other instruments, will help determine the thermal conditions of the core and mantle.

All of InSight’s instruments are designed to probe the interior geophysical conditions of Mars, but the purpose of its mission goes well beyond that.

InSight’s goals are a broader investigation of the very early formation of all the terrestrial planets of the inner solar system—Earth, Venus, Mercury, and Mars.

All of these rocky worlds are believed to have originally formed through a process called accretion, in which primordial materials in the young solar system were pulled together by gravity into larger and larger objects, snowballing to become the planets.

At some point in the process, the planets underwent a process called differentiation, in which heavier materials sunk toward their centers, light materials floated toward the surface, and the structure of core-mantle-crust that we see today took shape. However, scientists’ understanding of how this process unfolded is vague.

Because Mars is far less geologically active than Earth, it preserves in its structure and in the thermal state of its interior a record of its ancient physical state. Much of the evidence of Earth’s early formation has been more or less erased over eons of tectonic churning.

While InSight gets repaired, there are still two operational rovers up there—Opportunity and Curiosity—and four orbital spacecraft, MAVEN, Mars Reconnaissance Orbiter, Mars Odyssey, and the European Mars Express.  So, the disappointment of the two-year delay in putting the stethoscope to Mars’ heartbeat is softened by all the other incredible data coming to us.

In the winding-down period of its more than 12-year mission exploring the Saturn system, NASA’s Cassini spacecraft has spotted the tallest mountain of Saturn’s largest moon, Titan, a peak in the Mithrim Montes range near the equator that rises over two miles above the moon’s surface.

The Cassini spacecraft measured the peaks of Mithrim Montes using its radar instrument to penetrate the layers of thick, smoggy haze in Titan’s atmosphere.

The highest of the peaks is 10,948 feet high, and most of Titan’s highest peaks, which are found near the equator, are close to 10,000 feet tall. Comparably high mountains on Earth include Cathedral Peak in Yosemite, Mount Lassen, and Telescope Peak in Death Valley National Park (whose entire height, from sea level to summit, can be viewed in one stunning vista from the valley floor).

Extreme Mountaineering

The discovery of nature’s geological extremes—extreme heights, extreme depths, extreme scales—is something that may excite the adventurous spirit in us all. However, scientists have a more practical purpose for taking such measurements, in this case probing the origins and understanding the forces that form the solar system’s highest mountain ranges.

Though one might climb a mountain “because it’s there,” the mountains themselves are there for a more concrete reason. Mountains are structures formed by dynamic forces that actively push them upward—for example, the collision of tectonic plates, which is the driving force uplifting Earth’s tallest mountain ranges. Volcanism is another process that builds mountains. And, on some worlds, like the planet Mercury, uplifted features may be formed when the planet or moon cools and contracts, and wrinkles form on its surface.

Mountains, Young and Old

On planets and moons with atmospheres—in particular, those with active surface weathering processes—mountains gradually wear down as erosion scours their surfaces. On Earth, the towering Himalayas, Andes, and Rocky Mountains are examples of relatively young mountain ranges pushed upward by the collisions of crustal tectonic plates.

The Appalachian Mountains along the east coast of North America, today a gentle range whose highest points are less than 7,000 feet above sea level, have been weathered down since their formation 480 million years ago. In its heyday, however, the Appalachians were a mighty range comparable to the Alps and the Rockies.

What Is at Work Under Titan’s Surface?

The presence of Titan’s tall mountains is intriguing, particularly in light of the fact that Titan’s thick atmosphere and erosive weather cycle of liquid-methane precipitation and runoff are at work wearing them down. This suggests that some active process may have raised the mountains relatively recently.

Candidates for the mountain-building forces responsible for Titan’s ranges include tectonic activity driven by a deep subsurface ocean of water that Titan’s crust floats on, tidal effects from Saturn’s gravity, or the contracting of the moon’s surface as it cools. By studying their size, location, and distribution, scientists hope to learn which of these processes might be the culprit, and how it may still be shaping Titan’s surface today.

Ranging Across the Solar System

Throughout the solar system we explore the tallest mountains and mountain ranges of many planets and moons in order to reveal unseen processes masked by their surfaces.

Pluto’s Norgay Montes tower 11,000 feet high, while Mercury’s Caloris Montes reaches a similar 10,032 feet. On Venus, Maxwell Montes, whose origin is still under debate, climbs to 35,904 feet. On Mars, the vast shield volcano Olympus Mons—the highest mountain in the solar system—rises a breathtaking 69,650 feet above the Martian surface.

Earth’s own Mount Everest, at 29,029 feet above sea level, along with the entire Himalayan mountain range, was uplifted by the collision of the Indo-Australian and the Eurasian crustal plates.

The Cassini mission is coming to a close. In September 2017, the spacecraft will be deliberately de-orbited and burn up in the atmosphere of Saturn, ending a 13-year expedition of remarkable discovery.

Between now and then, Cassini will make about dozen close flybys of Titan, so there’s still time for a few more long-distance extreme-mountaineering runs….

Seventy-five million miles out in space is not where you want to be when an emergency crops up, but that’s exactly where NASA’s Kepler spacecraft was earlier this week when the red lights and sirens went off back at mission control.

Kepler suddenly placed itself in “emergency mode,” for reasons under investigation. Mission operators at Ames Research Center in Mountain View, California were given immediate priority to use NASA’s Deep Space Network of radio dishes to communicate with Kepler and download data to help them diagnose the problem.

Despite a 13-minute round-trip communication delay, project engineers managed to get Kepler out of emergency mode and placed the spacecraft into a stable waiting state, as they analyze the diagnostic data and figure out what happened.

Mission managers hope to return Kepler to science operations soon, once the spacecraft is given a clean bill of health.

A Seven-Year Hunting Trip

Kepler is a sun-orbiting space telescope designed to discover small, Earth-sized planets orbiting their stars at the right distance so that liquid water could exist on their surfaces—planets within their stars’ so-called “Goldilocks Zone,” or Habitable Zone.

Since its launch in 2009, the Kepler spacecraft has detected and confirmed about 1,080 extrasolar planets, and 4,966 candidate exoplanets awaiting confirmation, adding greatly to the totals of all exoplanet discoveries. Of these detections, about a dozen are smaller than twice Earth’s size, and orbit within their stars’ Habitable Zones, making them prime prospects for possessing life-friendly environments.

Gravitational Microlensing

Kepler was preparing to begin a search for distant exoplanets through measurements of their effect on the light of more distant stars, a science campaign that was to begin on April 10th. As an exoplanet passes between Earth and the more distant star, its gravity can bend the star’s light and focus it toward Earth, causing a distortion in the starlight that Kepler can detect.

This effect is called “gravitational microlensing,” and is similar in concept to how a glass lens bends and focuses light, but on a much larger scale.

Gravitational microlensing, then, lets us detect the presence–as well as estimate the masses–of planets so far away that they are normally undetectable. The most distant exoplanets yet discovered were detected by this method, some as far as the central core of the Milky Way Galaxy, tens of thousands of light years away.

A Change in Kepler’s Game Plan

The detection of exoplanets by gravitational microlensing was not Kepler’s original method of discovery.

Kepler’s initial exoplanet-finding tactic was to measure the dimming of a star’s light as one of its own planets crossed in front of it, an event called a transit.

Kepler spent three years staring at about 145,000 stars near the constellation Cygnus, waiting for any of them to “blink” as a planet transited. By “staring” at the same patch of stars for multiple years, Kepler was also able to confirm planets at Earth-like distances from their stars—planets that we can only observe to transit once in many months, or years.

But in 2012, one of Kepler’s four stabilizing gyroscopes stopped working, followed in 2013 by a second gyroscope failure. The loss of these gyroscopes meant that Kepler could no longer remain pointing steadily at its target patch of space, and continued observations of planetary transits could no longer take place.

Then in May of 2013, a new operating mode was approved that would allow Kepler to continue conducting scientific investigations using only its two remaining gyroscopes.

“K2” was born.

In its K2 incarnation, Kepler can conduct a number of observations, including detecting exoplanets through gravitational microlensing, searching for supernovas in distant galaxies, and studying young stars in clusters to expand our understanding of how planetary systems form.

With any luck, K2 will resume science operations in a week or so, bringing to knowledge yet more strange and distant worlds.

NASA’s farthest-flung solar-powered robotic probe, Juno, has finally crossed over into Jupiter territory, where the gravitational attraction of the gas giant planet is stronger than the sun’s. Juno is now on the threshold of a mission that promises to solve many long-standing mysteries about our solar system’s largest planet.

On July 4, Juno will become only the second spacecraft to enter orbit around Jupiter, over twenty years after the end of the successful Galileo mission.

Equipped to observe not only the outward appearance and composition of Jupiter, Juno’s payload of instrumentation will allow scientists to probe deep beneath the planet’s surface and hopefully solve long standing puzzles about Jupiter’s structure, interior conditions and even its origin.

Jupiter may be the largest planet, and the closest of the gas giant worlds in the outer solar system, but that does not mean its secrets have all been revealed to us. Most of Jupiter lies hidden beneath a veil of cloud, a shroud that ordinary cameras cannot see beyond.

Past robotic missions and telescopic observations have told us a great deal about Jupiter’s cloud-banded outer face, its composition of mostly hydrogen and helium, and its powerful magnetic field — strongest of any planet — that exerts influences well beyond the realm of its more than 67 moons.

Jupiter’s moons as well — in particular the four large “Galilean” moons discovered by Galileo over 400 years ago — have been revealed as remarkably interesting and diverse worlds of their own. One of them, Io, is the most volcanically active object in the solar system, with nearly 400 active volcanoes spewing plumes of sulfur and sulfur dioxide. Another, Europa, likely hides an ocean of liquid water beneath its icy crust, perhaps as deep as 30 miles and containing more water than all of Earth’s oceans — making Europa one of the most exciting possibilities for finding some form of life.

But Juno’s primary mission is to investigate Jupiter itself — and not just its cloud-painted outward face, but the deep dark depths of its interior.

What lies inside Jupiter? Being a gas giant planet, it is believed that Jupiter is all or mostly atmosphere — or more accurately, fluid: a thick shell of ever-denser hydrogen and helium that the unimaginable pressures deep down force to behave in ways we don’t think of as “gas-like.”

At some depth, hydrogen should be compressed to the point where it would become “metallic,” or electrically conductive like a metal, though still fluid — maybe not unlike the liquid metal mercury, which is used in some thermometers. It is thought that Jupiter’s powerful magnetic field is generated by electrical currents within these metallic hydrogen layers.

There is plenty of other “inside information” about Jupiter that scientists want to get their hands on. Finding out how much water Jupiter contains may help determine where and how Jupiter originated long ago. Did it form where we find it today — about five times as far from the sun as Earth — or, as a competing theory suggests, did it form farther from the sun and migrate to its present location? Jupiter’s internal water content would be an indication of the environment that produced it, so Juno may help settle this long standing question.

What is the source of the great storm systems we see on Jupiter, including the famous “Great Red Spot,” a gargantuan anticyclone that has been swirling just south of Jupiter’s equator for at least 300 years? How deep do the influences that generate and sustain these storms go? That’s an easy question to answer on Earth, where the roots of weather systems don’t go much deeper than Earth’s solid and watery surface. But on a planet where the atmosphere may extend many tens of thousands of miles, this is an open question.

And what lies at Jupiter’s core? Is there a rocky or metallic core down there under all the hydrogen and helium? Has carbon been compressed over time into diamond crystals that have settled to Jupiter’s center, as some have suggested might be possible?

Juno will orbit Jupiter in a “polar” orbit, circling the planet in a north-south orientation that will carry it repeatedly over Jupiter’s geographic and magnetic polar regions. Juno will make detailed measurements of the powerful magnetic fields that extend into space from within Jupiter, as well as detect tiny fluctuations in Jupiter’s gravitational field authored by internal structures (a little like reading Jupiter’s interior in Braille).

While conventional cameras and telescopes cannot see beneath Jupiter’s cloud tops, just as your eyes cannot see through a thick window curtain, the magnetic energy and gravitational variations originating in the interior carry information that we can use to probe those depths.

Juno will, in effect, probe beyond the planet’s surface appearance and give us a glimpse of what lies inside….

NASA’s Spitzer Space Telescope has recently mapped the surface temperatures of a “super-Earth,” giving us a rare glimpse into the environmental and weather conditions on a distant extrasolar planet.

The exoplanet in question is called “55 Cancri e”— one of five exoplanets discovered orbiting the star 55 Cancri, about 40 light years away in the constellation Cancer. Of the five, “e” is the smallest — though still weighs in at about 8 times the mass of the Earth, and twice the diameter.

55 Cancri e is about 25 times closer to its star than Mercury is to our sun. At this tight distance it takes less than 18 hours to revolve once around its star — so, 55 Cancri e’s year is shorter than a day on Earth!

Since the planet is so close to its star, its rotation is most likely “locked” by gravitational tidal forces, so that the same side always faces the star — not unlike how the Moon is tidally locked to the Earth, always presenting the same face to us.

Spitzer made observations of the super-Earth over several revolutions, which has allowed it to map heat variations over the entire surface (night side and day side) multiple times. This map has revealed some remarkable things about 55 Cancri e.

For one, the permanently day-lit side of the planet has a peak temperature of about 4,400 degrees Fahrenheit — hot enough to melt lead, iron, silicon and many other substances. By contrast, temperatures on the hemisphere of never-ending night drop sharply to lows of only 2,060 degrees Fahrenheit — not exactly chilly, but low enough for lava to “freeze” into solid rock.

The huge difference in temperature between the day and night sides of 55 Cancri e tells us that the planet does not have an atmosphere capable of spreading heat evenly around the globe — which could mean little or no atmosphere, or an atmosphere that isn’t great at globally transporting heat.

By contrast, Venus possesses a super-thick atmosphere of carbon dioxide gas, which spreads heat with great efficiency to give Venus about the same (hot) temperature across its entire surface — day side, night side, equatorial zone and polar regions alike.

The Spitzer heat map also tells us that the day-side surface is likely to be inundated with rivers and large pools of molten lava — lava that under the extreme temperatures may behave in a “super-fluid” state, flowing more like the water in Earth’s oceans than the sluggish toothpaste crawl of much cooler Earthly lavas.

On the flip-side of the planet, where it is “chilly” enough for lava to solidify, we can envision a hot, dark landscape of solid lava rock—maybe under a brilliant starry sky, depending on the nature of any atmosphere 55 Cancri e may possess.

We may also imagine a twilight zone between the two extreme hemispheres. Could we find landscape forms of solid rock and liquid lava, maybe a super-Earth, super-heated version of Norway’s fjords? Whatever the case, 55 Cancri e is definitely an imagination-teaser!

Further investigation by NASA’s up and coming James Webb Space Telescope, which will be larger than Hubble or Spitzer and make observations at infrared wavelengths, will reveal even more about this, and other, fascinating extrasolar worlds.

NASA’s next robot to crawl across the surface of Mars — the Mars 2020 rover — recently crossed a major milestone when it received approval to launch in the summer of 2020, for a February 2021 landing.

Like its predecessor Curiosity, which is currently exploring the slopes of Mount Sharp in Gale Crater, Mars 2020 is a six-wheeled nuclear-powered rover that will land on Mars using a rocket-driven “sky crane” system.

Unlike Curiosity, whose mission is to assess Mars’ past geologic history and the role water played in it, Mars 2020 is focused on a search for that thing we’ve all been waiting to hear news of: actual signs of past Martian life.

New Chances of Finding Signs of Martian Life?

Searching for evidence of life on Mars is not unlike prospecting for gold: it’s not easy to find, but you improve your chances of success by choosing the right region to explore, and then deciding the best spots to dig in. Just like a skilled prospector using eyes, ears, nose, tongue and all the experience earned on earlier expeditions, Mars 2020 is designed to maximize the chance of hitting pay dirt.

Though it will be deposited on the Martian surface using the same rocket-powered “sky crane” as Curiosity, improvements in operational technique and equipment will allow Mars 2020 to set down with about twice the precision.

This opens up a much wider variety of terrains where it may land in relative safety. And if there’s one thing that missions to Mars have shown us over the past forty years, it’s that the most interesting places to explore are some of the most challenging to negotiate.

Once on the ground, Mars 2020 will use a suite of advanced instruments. A high-resolution imager and spectroscopic analyzers will record chemistry and physical structures at a distance. This allows scientists back on Earth to make more educated decisions on where to send the rover for close-up inspection and digging.

Like Curiosity, Mars 2020 will be able to collect and analyze rock and soil samples in its small on-board laboratory. However its onboard equipment is designed to look for residues of life activity, not just water action.

In addition, Mars 2020 carries airtight tubes to store rock and soil samples. Up to thirty of these containers will be deposited at designated locations for future possible missions to collect and return to Earth for full laboratory analysis.

Mars 2020 also carries weather-measuring instruments, a rock-coring drill, and a feature never before used on another planet: ground-penetrating radar that will let it analyze sub-surface geologic structures.

The hopeful child in me envisions an opening scene from Jurassic Park, when ground-penetrating sonic vibrations were used to produce a sonogram of a dinosaur skeleton…though the adult in me says that’s way too much to expect!

Mars 2020 will also put an ear to the Martian environment, using a microphone system to record sounds from Mars’ surface, something we’ve never done before. The 2008 Phoenix lander was intended to capture sounds during the probe’s descent, but the microphone was never enabled due to landing safety concerns.

Why Is the Search for Martian Life Taking So Long?

2021 seems like a long time to wait, especially since the Mars 2020 mission will be focused on looking for life-signs on an alien world.

But it’s important to keep in mind that exploring a distant world via remote control is not an easy thing to do. Each mission peels off another layer of Martian mystery, and gives us more information to use in deciding where to send the next mission, and what to look for when it gets there. This process takes time, especially considering that launch windows to Mars occur only every two years.

Put into perspective, within my own lifetime we’ve gone from knowing practically nothing about Mars to understanding our neighbor as perhaps a previously Earthlike planet.

A life-friendly environment means there may have been plenty of opportunities for little Martian microbes to show up and thrive. And, the hopeful child and sober adult in me both expect, within my lifetime we’ll find them.

Berkeley scientist Jill Tarter was a key figure in launching the legendary program known as SETI. Her determination inspired Jodie Foster’s character in the 1997 film, Contact. In the first biography of her, Tarter recalls that SETI was no easy sell in Congress, and almost didn’t get off the ground.

Excerpted from Making Contact: Jill Tarter and the Search for Extraterrestrial Intelligence by Sarah Scoles, published by Pegasus Books. Reprinted with permission from the publisher. All other rights reserved. © Sarah Scoles.

On Columbus Day Eve, 1992, Jill Tarter paced the Arecibo Observatory control room, making sure every winding blue cable was in place, every signal pathway was sound, and every cryogenic dewar did its job. She looked out the panoramic window into the ancient sinkhole below. The giant radio dish—1,000 feet across—filled the space perfectly. Engineers had picked the telescope’s location by spreading out a topographic map of Puerto Rico and sliding a quarter around to see which valley could hold it. The quarter nestled precisely within a sinkhole 10 miles from the town of Arecibo. Three concrete pillars, which summer interns (and Tarter) occasionally climb to impress each other, rise from the edges of the basin, which the dish fills almost completely. Steel cables as thick as your forearm reach from the pillars toward the middle of the dish (although 500 feet above it). They hold aloft the radio-wave detectors and the electronics that make this huge contraption more than just a big bowl of chicken wire.

The Columbus Day Eve sun began to set, and the sky streaked the colors of an airbrushed ’80s T-shirt. Maybe somewhere else, on some other planet, some other sky was streaked the same colors. Maybe someone was there to watch. These someones wouldn’t know what the ’80s or T-shirts were, but they would know starsets.

Tarter turned from the window and prepared to test the equipment with Backus.

“Ready?” he asked.

She nodded.

They pointed the telescope toward Pioneer 10, testing just like always. It showed up, a slash on the screen, just like always. Then, they turned toward a few stars—more tests. The computers they had built talked back to them, delivering good and unexpected news: they had found an interesting signal, interesting enough to “send a shiver of excitement through everyone in the control room,” Backus told the New York Times. “Then it struck me,” Backus continued. “Maybe what we were seeing on the screen is exactly what we are looking for. Sometime in the next couple of weeks we might do it for real. Who knows?” The signal turned out to be from a physical, not a biological, source.

Tarter stayed in the control room until 3 a.m. When she walked back to her two-room hut, with its floral-upholstered couch and bamboo table, the chirping of the jungle frogs was deafening. But the natural noise was a welcome change, taking her mind for a moment off the nervous hum of electronics.

A few hours later Tarter awoke and got dressed for the press. It was the day Her Majesty’s Royal SETI began. She prepared to keep the Cyclops Report’s promise. Outside the control room, where coder Jane Jordan’s software prepared to search for alien signals, a crowd gathered, including Shana and her brand-new husband, who also took their honeymoon photos on the telescope’s catwalk during the same trip.

Billingham stepped before the crowd to give an opening speech. He had spent even longer than Tarter waiting for this moment. “This is the beginning of the next age of discovery,” he said. “We sail into the future, just as Columbus did on this day five hundred years ago. We accept the challenge of searching for a new world.”

The audience, including the scientists who had worked for more than a decade to make sure someone like Billingham could make a speech something like this, smiled taut smiles and looked out toward the radio dish.

“If you’re going to do this,” Barney­ Oliver had long ago told Tarter, setting a gold statue of Sisyphus and his boulder on her desk, “you’re going to need this. Because you’re going to roll an awful lot of rocks up an awful lot of hills, and they’re all going to come tumbling down. And you’re going to have to do it again. That’s just the price of trying to do something new.”

Tarter thought maybe the boulder had finally crested—today, Columbus Day, 1992. She pressed the buttons that told the telescope to start observing. “We begin the search,” she declared.

Simultaneously, Sam Gulkis did the same at the Goldstone telescope in California, starting the survey portion of the search. The Arecibo Radio Telescope pointed at the star GL615.1A, 63 light-years away in the constellation Hercules. GL615.1A is like our sun but smaller and cooler. God, this is a really amazing day for humans, Tarter thought. Here we are launching this exploration simply because we’re curious. That’s a big milestone for humanity. We’re doing this.

A New York Times reporter covering the event waxed philosophical, too, about the telescope itself: “There was speculation as to what future archeologists might surmise if they happened on the ruins of these stone pillars, aluminum panels and huge steel cables and girders. Here a society with scientist-priests communicated with their gods in the heavens? Some Columbuses sought the cosmic Indies, never found? Or this was the place where humans listened in the jungle stillness and for the first time heard that they are not alone in the universe?”

Senator Richard Bryan, perhaps via this very New York Times piece (newspapers were always causing trouble for SETI), caught wind of the celebration. He had wanted SETI gone, and here SETI was, starting up in earnest. At a hearing for fiscal year 1994, Bryan’s words sent a shiver through Tarter when she watched on C-SPAN: “Mr. Goldin,” Bryan said to Daniel Goldin, the head of NASA, “something in your budget doesn’t pass the smell test.”

“He was talking about SETI,” Tarter says.

Goldin says he was caught off-guard by the congressional opposition, in general, to SETI. As a new administrator, he knew the research program existed, but he didn’t know much about its specifics. He says he wished someone had warned him about what he was walking into. “I was so frustrated that I had only a layman’s understanding of the program,” he says, “and I’m a detail person, and I always do homework before I do anything, and especially before hearings.”

During that hearing, Tarter leaned toward the television, like it was a black box that could tell her future. Having knocked on as many White-House doors as she could, all she could do was wait for the final hearing, where people she didn’t know would decide whether her career lived or died. “It’s hard to elevate the consciousness of Congressmen from mundane to heavenly matters,” Barney Oliver once said in an interview with the Times.

In September 1993, Congress met to talk about science and technology projects. To build solid rocket motors or to not build solid rocket motors? To build the superconducting supercollider (yes, a real thing) or to not build the superconducting supercollider? They had been going at it for days, slashing this and cutting that. Tarter watched C-SPAN for hours, thinking how much more boring it must be in that room. She switched off the television and went to pack her suitcase. She was scheduled to give a talk in Huntsville, Alabama, as part of the Wernher Von Braun Lecture Series at NASA’s Marshall Space Flight Center. The whole night—meant for the public—was about exploration and the human spirit. Tarter would speak about SETI, of course, and folk musician John Denver would serenade the audience with world-uniting songs.

She stood backstage as Denver performed “White Horses,” swaying and watching the crowd do the same. They were all there together, in this moment in the dark in Huntsville, thinking about the long future, the big space, and their place in it all. It was kind of beautiful. But at the same time, Congress sat behind long desks discussing whether to interrupt that line of questioning.

“It was all overwhelming,” she says in 2015, looking toward the wall of her Berkeley home, where the plaque commemorating the Von Braun lecture hangs. “I was overwhelmed by the star power on the stage and the DC shenanigans threatening to terminate my world.”

Just before she was to succeed Denver on the stage, a staffer whispered in her ear: Senator Bryan had put in an eleventh-hour proposal to cancel the SETI program. Congress would vote in the morning. She calls Denver’s performance a Rocky Mountain high. This whispered news, though, she calls a Death Valley low. She debated whether she should give her lecture as planned or instead deliver an impassioned plea to bombard senators with letters of SETI support.

“It wouldn’t have done any good,” she says.

Tarter usually accepts the boulders and the grades up which they must be shoved. But she for once accepted that another person’s will could defeat her own.

The next morning, before the debate began, she left on a jet plane back to California. The congressional conversation took place while she was in the air. Even cruising altitude was not quite high enough to give perspective. While she looked down at the clouds and flipped through Skymall, her father’s voice came into her head. “I don’t see why you couldn’t do anything, if you work hard enough.”

Maybe he had been wrong.

She ran to a phone as soon as the plane landed.

“Are we okay?” she asked.

“No,” a colleague said. “It’s done.”

Bryan had won. His press release, typed onto stationery mocked up to look like the SETI Institute’s letterhead, was headlined “Senator Bryan Ends the Great Martian Chase. “As of today, millions have been spent and we have yet to bag a single little green fellow,” the release continued. “Not a single Martian has said ‘take me to your leader,’ and not a single flying saucer has applied for FAA approval. It may be funny to some, except the punchline includes a $12.3 million price tag to the taxpayer.”

“Don’t leave me alone with any sharp objects,” Tarter said to her husband, Jack Welch, when she arrived home. Just a year earlier, at the High Resolution Microwave Survey launch, she had been so hopeful, had thought such grand thoughts, had compared her team to Columbus, for God’s sake. And now the dream was dead. She couldn’t even push a boulder if she’d tried. All the boulders had, in fact, been summarily carted away.

To the world, though, she showed a stoic face. “This is an enormous setback,” she said to the New York Times. “NASA has spent 20 years and more than $50 million to develop sophisticated digital receivers capable of listening to tens of millions of frequencies at a time. Now, with the observations getting under way, the project is killed.”

Barney Oliver was less circumspect when he wrote for the science newsletter Signals:

Millions of transistors, memory cells, and other high-tech products of our ingenuity have been woven into a brain whose sole aim in life is to detect and verify the origin of tiny signals—less energetic than the smallest atomic particle— that have crossed the light years we cannot. Such signals will tell us that we are not alone, that the astonishing process that has produced us out of the fiery furnace of the Big Bang has also occurred elsewhere. Lo, from that single fact, all our philosophy would be enriched. To save the American Taxpayer about eight cents per year, we are to be denied the chance to explore the universe and the sentient life forms that fill it.

It was the kind of oratory Tarter would later give. But that October she could only mope and avoid her knife block. The next day, though, a call came from the targeted-search project scientist John Dreher, who had joined the team in 1989 after leaving a physics position at the Massachusetts Institute of Technology.

“You know,” he said, “if what we were doing yesterday made sense, it’s still going to make sense on Monday. We just have to find some other way.”

Ed. Note: despite occasional setbacks, and some continued opposition, SETI is still alive and well in 2017, and currently raising funds for a new optical approach to the search.