Test-Bed Rover is Now Stuck — Which is a Good Thing!

With a slope of about 10 degrees and a pointy rock under the test rover's belly, this sandbox setup at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is ready for engineers to use the test rover to assess possible moves for getting Mars rover Spirit out of a patch of loose Martian soil. Credit: JPL

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Engineers at the Jet Propulsion Laboratory have intentionally driven their engineering rover into soft soil in a sandbox testbed, to simulate how the Spirit rover is stuck on Mars. And they did a good job of it, too, as the test rover, called SSTB1, is stuck, as well, with its wheels spinning and going nowhere. The science team has confirmed a rock on Mars, underneath Spirit is touching the underside of the rover, so engineers have placed a similar looking rock in the test sandbox, as seen above.

“We want to experiment with different extraction techniques down here on Earth before we actually do them for real on Mars,” said John Callas, project manager for the Mars rovers. “Our expectation is that it will some time to get Spirit out, so we will be able to get a better feel for that here in this facility to see how well the techniques work and how long it will take for them to work.”

The rover team spent several days of preparing a sloped area of soft, fine soil to simulate Spirit’s current sandtrap on Mars. On June 30 they maneuvered the test rover around, driving the wheels to the loose soil where the rover would sink and slide to the side, with a slope of about 10 degrees, as engineers believe Spirit has done on Mars.

You can follow the work being done to free Spirit from her predicament at the Free Spirit website. JPL regularly posts updates and videos showing what the rover teams are doing, and currently you can see a movie of how the test rover was driven in the sandbox to get stuck.

A test rover rolls off a plywood surface into a prepared bed of soft soil.  Credit: JPL
A test rover rolls off a plywood surface into a prepared bed of soft soil. Credit: JPL

There are actually two test vehicles, and the folks at UnmannedSpaceflight.com have a page explaining the differences, as well as other FAQs about the attempts to free Spirit. The one being use for this current test, SSTB1 is a full size replica of the MER vehicles, but it has a few differences such as no solar panels, and a few other minor missing parts. It has the same mass as the ones on Mars, which means it has a higher weight on Earth than the MERs have on Mars.

The other test rover, SSTB Lite, is a stripped down vehicle with same wheel size, actuators and suspension system, but has other major components missing which gives it a weight on Earth that is similar to the weight of MER on Mars. However, when the Opportunity rover was stuck a couple of years in the Purgatory dune, engineers found that SSTB1 behaved more similarly to the MER vehicles, possibly because both the SSTB1 and the soil were subject to the same gravity vector.

Mosaic of the area around Home Plate where Spirit remains stuck was made especially for Spaceflight Now (Used by permission).  Credit: Kenneth Kremer, Marco DiLorenzo, NASA/JPL/Cornell/Spaceflight Now.  Click for larger image.
Mosaic of the area around Home Plate where Spirit remains stuck was made especially for Spaceflight Now (Used by permission). Credit: Kenneth Kremer, Marco DiLorenzo, NASA/JPL/Cornell/Spaceflight Now. Click for larger image.

So, just where is Spirit on Mars? Take a look at this great image created by Ken Kremer and Marco DeLorenzo of UnmannedSpaceflight.com, showing Spirit’s current location. It shows smooth area in the foreground, that concealed slippery water related sulfate material where rover became stuck. Once free, Spirit will drive to area near the unusually capped hill ahead designated Von Braun to sample water related evidence there. Let’s hope the engineer’s work here on Earth will “Free Spirit” and enable explorations of Von Braun, and beyond.

Caption for mosaic above: Mosaic of the area around Home Plate where Spirit remains stuck was made especially for Spaceflight Now (Used by permission). Credit: Kenneth Kremer, Marco DiLorenzo, NASA/JPL/Cornell/Spaceflight Now. Click the picture for a larger image.

Sources: “Free Spirit” website, Unmanned Spaceflight, Spaceflightnow.com

Landforms Indicate “Recent” Warm Weather on Mars

Retrogressive scarps with cuspate niches, long branching spurs and associated fluvial-like tributary channels. Credit:NASA/JPL/UofA

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Remember the polygon-shaped landforms at Mars north polar region that the Phoenix lander studied? The polygons are produced by seasonal expansion and contraction of ground ice, and these shapes have been found in other regions on Mars as well. New studies of images from the HiRISE camera on the Mars Reconnaissance Orbiter indicates that the Martian surface near the equator experienced freeze-thaw cycles as recently as 2 million years ago. This means Mars had significantly warmer weather in its recent past, and has not been locked in permafrost conditions for billions of years as had been previously thought.

The HiRISE images show polygon-patterned surfaces, branched channels, blocky debris and mound/cone structures.

Dr. Matthew Balme, from The Open University, made the new discovery by studying detailed images of equatorial landforms that formed by melting of ice-rich soils, such as the polygons, branched channels, blocky debris and mound/cone structures. These are all found in an outflow channel, thought to have been active as recently as 2 million to 8 million years ago. Since the landforms exist within, and cut across, the pre-existing features of the channel, this suggests that they, too, were created within this timeframe.

Full resolution view of domed polygons from HiRISE.  Credit: NASA/JPL/U of A
Full resolution view of domed polygons from HiRISE. Credit: NASA/JPL/U of A

All of these features are similar to landforms on Earth typical of areas where permafrost terrain is melting.

“The features of this terrain were previously interpreted to be the result of volcanic processes,” said Balme. “The amazingly detailed images from HiRISE show that the features are instead caused by the expansion and contraction of ice, and by thawing of ice-rich ground. This all suggests a very different climate to what we see today.”

This also means as the shorter the time period since the last warm weather on the planet, the better the chance that any organisms that may have lived in warmer times are still alive under the planet’s surface.

“These observations demonstrate not only that there was ice near the Martian equator in the last few million years, but also that the ice melted to form liquid water and then refroze,” said Balme. “And this probably happened for many cycles. Given that liquid water seems to be essential for life, these kinds of environments could be a great place to look for evidence of past life on Mars.”

Source: STFC

Rover Update With Video

Image from Spirit's front hazcam from sol 1940. Credit: NASA/JPL

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Here’s a rover update: Spirit remains stuck in her location on the west side of Home Plate, and work continues at JPL for testing on how to extract the rover from being embedded in soft soil. A rock may be underneath Spirit, keeping her from moving, but more images are being taken by the microscopic camera at the end of the robotic arm to try and determine exactly what is going on under and around the rover. But with a boosted power supply, Spirit has also been busy making scientific observations of her surroundings. And one more thing, which would be extremely fun, rover driver Scott Maxwell hinted on Twitter that Spirit has so much power now from a recent wind event that cleared off her solar panels that she may attempt to make overnight observations. So stay tuned for PANCAM images of the Martian night sky!

Enjoy this video update on the Mars Exploration rovers by another rover driver, Ashley Stroupe.

As of Sol 1932 (June 9, 2009), Spirit’s solar array energy production is at 828 watt-hours. Total odometry remains at 7,729.93 meters (4.80 miles).

Meanwhile over on the other side of the planet, Opportunity continues to drive south on the way to Endeavour crater. On Sol 1906 (June 4, 2009), the rover completed a 69-meter (266-foot) drive due south. Elevated actuator currents with the right-front wheel continue to cause concern. On Sol 1910 (June 8, 2009), the planned drive stopped early because a multi-wheel current limit threshold was exceeded. A diagnostic maneuver on the next sol was successful indicating the cause on the previous sol was due to the elevated right-front wheel motor currents.

The view from Opportunity on sol 1912.  Credit: NASA/JPL
The view from Opportunity on sol 1912. Credit: NASA/JPL



A long, backward drive was performed on Sol 1912 (June 10, 2009). Driving backwards is one technique to mitigate the elevated wheel currents. However, wheel currents continued to be elevated after that 72-meter (236-foot) drive. Further resting of the rover’s actuators is being considered.

The plan ahead includes opening the shroud of the miniature thermal emission spectrometer (Mini-TES) to expose the instrument’s dust-contaminated elevation mirror to the environment. This is an attempt to allow the wind environment to clean dust off the mirror.

As of Sol 1912 (June 10, 2009), Opportunity’s solar array energy production is 431 watt-hours. Opportunity’s total odometry is 16,569.05 meters (10.3 miles).

Lightning Detected on Mars

An illustration of a dust storm on Mars. Credit: Brian Grimm and Nilton Renno

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The first direct evidence of lightning has been detected on Mars. Researchers from the University of Michigan found signs of electrical discharges during dust storms on the red planet using an innovative microwave detector . The bolts were dry lightning, said Professor Chris Ruf. “What we saw on Mars was a series of huge and sudden electrical discharges caused by a large dust storm. Clearly, there was no rain associated with the electrical discharges on Mars. However, the implied possibilities are exciting.”

The Space Physics Research Laboratory at the University of Michigan developed the kurtosis detector, which is capable of differentiating between thermal and non-thermal radiation. The device took measurements of microwave emissions from Mars for approximately five hours a day for 12 days between May 22 and June 16, 2006.

On June 8, 2006 both an unusual pattern of non-thermal radiation and an intense Martian dust storm occurred, the only time that non-thermal radiation was detected. Non-thermal radiation would suggest the presence of lightning.

Electric activity in Martian dust storms has important implications for Mars science, the researchers said.
“It affects atmospheric chemistry, habitability and preparations for human exploration. It might even have implications for the origin of life, as suggested by experiments in the 1950s,” said Professor Nilton Renno of the university’s Department of Atmospheric, Oceanic and Space Sciences.

“Mars continues to amaze us,” said Michael Sanders, manager of exploration systems and technology at the National Aeronautics and Space Administration’s Jet Propulsion Laboratory and a researcher involved in the study. “Every new look at the planet gives us new insights.”

The new findings are to appear in an upcoming issue of the journal Geophysical Research Letters.

Source: University of Michigan

Looking for (Former) Lakeshore Property? HiRISE Finds It on Mars

This is reconstructed landscape showing the Shalbatana lake on Mars as it may have looked roughly 3.4 billion years ago. Data used in reconstruction are from NASA and the European Space Agency. Credit: Image credit: G. Di Achille, University of Colorado

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If you’re in the market for some remote lakeshore property where you can get away from it all, this might be just what you’re looking for. Located in a secluded, pristine setting, this must-see property might be one of a kind. It’s very remote; – did I mention this lakeshore is on Mars? And, oh — it happens to be a former lakeshore.

While lakeshore property on Mars might sound like the biggest real estate swindle ever, the news of the first definitive lakeshore on Mars is momentous. Using images from the HiRISE Camera on the Mars Reconnaissance Orbiter, a University of Colorado at Boulder research team has discovered indications of a deep, ancient lake, estimated to be more than 3 billion years old.

The lake appears to have covered as much as 80 square miles and was up to 460 meters (1,500 feet) deep — roughly the equivalent of Lake Champlain bordering the United States and Canada, said CU-Boulder Research Associate Gaetano Di Achille, who led the study. The shoreline evidence, found along a broad delta in a region called Shalbatana Vallis, includes a series of alternating ridges and troughs thought to be surviving remnants of beach deposits.

“This is the first unambiguous evidence of shorelines on the surface of Mars,” said Di Achille. “The identification of the shorelines and accompanying geological evidence allows us to calculate the size and volume of the lake, which appears to have formed about 3.4 billion years ago.”

HiRISE image from Shalbatana Vallis. Credit: NASA/JPL/ U of AZ
HiRISE image from Shalbatana Vallis. Credit: NASA/JPL/ U of AZ

An analysis of the HiRISE images indicate that water carved a 50 km (30 mile) -long canyon that opened up into a valley, depositing sediment that formed a large delta. This delta and others surrounding the basin imply the existence of a large, long-lived lake, said team member Brian Hynek, also from CU-Boulder.
“Finding shorelines is a Holy Grail of sorts to us,” said Hynek.

In addition, the evidence shows the lake existed during a time when Mars is generally believed to have been cold and dry, which is at odds with current theories proposed by many planetary scientists, he said. “Not only does this research prove there was a long-lived lake system on Mars, but we can see that the lake formed after the warm, wet period is thought to have dissipated.”

Planetary scientists think the oldest surfaces on Mars formed during the wet and warm Noachan epoch from about 4.1 billion to 3.7 billion years ago that featured a bombardment of large meteors and extensive flooding. The newly discovered lake is believed to have formed during the Hesperian epoch and postdates the end of the warm and wet period on Mars by 300 million years, according to the study.

The deltas adjacent to the lake are of high interest to planetary scientists because deltas on Earth rapidly bury organic carbon and other biomarkers of life, according to Hynek. Most astrobiologists believe any present indications of life on Mars will be discovered in the form of subterranean microorganisms.

Close-up of region in Shalbatana Vallis. Credit: NASA/JPL/U of A
Close-up of region in Shalbatana Vallis. Credit: NASA/JPL/U of A

But in the past, lakes on Mars would have provided cozy surface habitats rich in nutrients for such microbes, Hynek said.

The retreat of the lake apparently was rapid enough to prevent the formation of additional, lower shorelines, said Di Achille. The lake probably either evaporated or froze over with the ice slowly turning to water vapor and disappearing during a period of abrupt climate change, according to the study.

Di Achille said the newly discovered pristine lake bed and delta deposits would be would be a prime target for a future landing mission to Mars in search of evidence of past life.

“On Earth, deltas and lakes are excellent collectors and preservers of signs of past life,” said Di Achille. “If life ever arose on Mars, deltas may be the key to unlocking Mars’ biological past.”

The team’s paper has been published online in Geophysical Research Letters, a publication of the American Geophysical Union.

One-Way Mission to Mars: US Soldiers Will Go

Sergeant First Class William H. Ruth III contemplates his current duty in a barren landscape in Afghanistan, and says he’s willing to lead a human mission to Mars.

An article published on Universe Today back in March of this year detailing former NASA engineer Jim McLane’s idea for on a one-way, one-person mission to Mars generated a lot of interest. The many comments on the subject posted here on UT and numerous other websites such as ABC News ranged from full support to complete disbelief of the idea. McLane’s concept has literally gone around the world, and a journalist from Spain, Javier Yanes who writes for the newspaper Publico shared with me his correspondence with a US soldier stationed in Afghanistan, who says that battle-hardened soldiers would be the perfect choice to send on a mission of no return to a new world. SFC William H. Ruth III says he and the men in the 101st Airborne Division are ready and willing to go.

SFC Ruth wrote, “While reading Jim McLane and Nancy Atkinson’s thoughts on Space Colonization, I started to realize that we ALL have lost our way. We have become so consumed by petty differences and dislikes of others that we all have forgotten our pre destiny of something better.”

And what is the ‘something better’ that Ruth envisions? Military personnel from different countries joining together to make “the ultimate sacrifice” of forging the way to establish an outpost on another world, like Mars.

“Here is an ‘out of the box’ idea,” Ruth writes. “Let the heroes of all our countries, for once, risk the ultimate sacrifice for something greater than one man’s idea. Maybe once let these men and woman that rise every morning and say ‘today I will stand for something and say ‘evil will not prevail, not on my watch.’ For once let them volunteer for us all, you never know, mankind, the human race. It might just catch on if we let it.”

Ruth continues, “Will we falter at a hint of death or danger? Or will we do now what so many in all of the world’s history has done before us. NASA of all thinking societies should understand this. Would there even be an America or NASA if a man named Columbus had not pursued a dangerous and possibly deadly voyage to a new world? He certainly had to consider whether or not he would ever return home to see all those he loved so dearly. But what of those aboard his ships, those that left Spain knowing that they would never return. Those few that willingly risked all for the chance at a new world and a new future, could they have possibly known what effects they would have had on the future due to their sacrifices? Now can we have enough vision to see our destiny, can we, for a moment, see past our petty differences of race and religion to see peace, prosperity and possibly a new world.”

3rd Platoon at Fire Base Ter-Wa, April 2008. SFC Ruth is first on the left.

Ruth says 15 years in the military has prepared him for such a mission. “So I am no fool and I am no stranger to what some might call high risks,” he says. “Hundreds of thousands of fighting men and woman from around this world have walked, rode, swam and even jumped into what some would call a high risk situation. Some even considered suicide missions, ones with low probability of success. And why, what did they risk all for? Each and every one of us, even those throughout this earth that has made that choice, risk all for what we believed would make our world better.”

Ruth first began pondering such a mission after reading a quote by Stephen Hawking on Space.com: “The discovery of the New World made a profound difference on the old,” Hawking said. “Spreading out into space will have an even greater effect. It will completely change the future of the human race, and maybe determine whether we have any future at all.”

Ruth sent an email to Space.com’s Anthony Duignan-Cabrera, which was posted on the LiveScience blog: “Here is an idea: Send battle-hardened, strong-minded soldiers and marines on the long trips into space. We are conditioned to live with the bare minimal (of) life’s necessities and are trained to be prepared for the worst conditions that any environment could throw at us. Hell, me and my men will go, set up a colony somewhere and await colonists to arrive.”

Javier Yanes read Ruth’s proposition and contacted him, sending him the link to the Universe Today article with McLane’s idea.

Ruth responded by sending Yanes a written statement called “A Soldier’s Perspective;,” Yanes wrote an article about Ruth in Publico, and shared Ruth’s proposal and pictures with me.

Ruth doesn’t agree with McLane’s idea of a one-person mission to Mars, but supports the one-way idea.

“I fully agree with NASA and others that it is completely dangerous and potentially deadly for anyone who sets out on this voyage,” he wrote. “But since when has that ever stopped anyone? A one way trip is the way to go about this, it is a proven fact of human history that when the human species is thrown into a no alternative situation, that they will prevail and survive.

The military would never send someone out alone, and Ruth thinks a multiple ship mission is the way to proceed, with three to four smaller vessels, with four to six crew members each.

Ruth admits that other might see sending soldiers into space as more like an invasion or occupation than exploration. “To those who share this concern, consider this for a moment and ask yourself, who else?” Ruth asked. “Who else has the mentality to volunteer to face certain danger and possibly death, thousands of miles away from their homes? I could think of a few hundred thousand that do it everyday across this planet.”

Ruth says that getting the worlds militarys involved with something other than making war with each other could change humanity’s future for the better.

“I wonder who will be the first to extend the hand of complete partnership, representing the whole human species?” Ruth asks. “Could this be the answer that so many have searched for? Could this one thing unite humanity in a new era of global cooperation and a new planetary respect for human life, unlike we know it today? My answer is ask me again when I’ve reached the new world!”

Mars Was Recently Blanketed By Glaciers

Mars is a dead world, unchanging for billions of years. Right? Maybe not. Researchers from Brown University have found evidence for thick, recurring glaciers on the surface of Mars. This means that the climate on Mars might be much more dynamic than previously believed. Perhaps the climate could change again. And liquid water underneath these glaciers might have given life a refuge over the eons.

Around 3.5 billion years ago, Mars was a completely different world, with liquid water right there on its surface. And then something happened that made it cold, dry, and quiet – too quiet. Apart from the occasional meteorite impact, planetary geologists thought that very little has happened on Mars since then.

In an article published in the journal Geology, scientists from Brown University released images showing how dynamic Mars might be. They found evidence that thick ice packs, at least 1 km (0.6 miles) thick and maybe 2.5 km (1.6 miles) thick coated Mars’ mid-latitude regions.

These ice sheets weren’t there last year, but they were there 100 million years ago, and maybe localized glaciers were flowing as recently as 10 million years ago. That’s yesterday, geologically speaking.

With activity this recent on Mars, that could mean that its climate might change often, and it could happen again. Maybe Mars wasn’t so dead for the last 3.5 billion years.

The images captured by NASA’s Mars Reconnaissance Orbiter showed a box canyon in a low-lying plain. The canyon clearly has moraines – deposits of rock that mark the end of the glacier, or the path of its retreat.

This discovery increases the possibility of life on the surface of Mars. At the bottom of the glaciers, crushed under kilometres of ice, liquid water would have formed into vast reservoirs. These could have served as sanctuaries for life.

Original Source: Brown University News Release

New ESA Rover Will Look For Life On Mars

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NASA’s Mars Exploration Rovers (MER) have been an outstanding success in their longevity and helping us to understand the role of water in Mars’ past. But Spirit and Opportunity don’t have the instruments on board to answer the question foremost in many people’s minds: Is there, or was there ever life on Mars?

A new spacecraft being readied by the European Space Agency (ESA) will have that ability. The rover for the ExoMars 2013 mission will have an on-board subsurface radar, a drill, and life-detection equipment as part of the scientific payload.

To help prepare for the mission, scientists at Aberystwyth University in Wales have simulated the surface of Mars in their lab to test the “roving” capabilities of the vehicle. Also being tested are the robotic arm for collecting samples and a panoramic camera.

The ExoMars mission will also have an orbiter that will scan for the best landing site for the rover. The rover is slated to travel to ten different locations in 6 months. The rover will use a radar system that can scan the surface and subsurface, a drill that can dig down 1-2 meters below the surface and gather a sample that will be brought to the onboard instruments that will look for life, past or present, in the Mars landscape.

A robotic arm that is part of this system is similar to arm that was part of the ill-fated Beagle 2 lander, that crashed on Mars surface in 2003. But the new arm has been improved, and it is hoped the arm will work with on-board cameras and to be able to acquire rock samples autonomously.

The rover will weigh about 140-180 kg, comparable to the NASA’s MER. The main scientific objectives of the ExoMars mission are to study the biological environment of Mars surface, to characterize the Mars geochemistry and water distribution and to identify possible surface hazards to future human missions.

The mission is scheduled to launch in 2013 and land on Mars in 2014.

Original News Source: BBC

No Humanoid on Mars, Just Rocks

Okay, once and for all, let’s make this clear. In the words of our esteemed Bad Astronomer, Phil Plait, “repeat after me:” A humanoid was not photographed on the surface of Mars. And NASA is not covering up this photo in the name of national security. Furthermore, human missions to Mars have not been cancelled because of this photo. These outrageous notions keep popping up in the media. The photograph, which was taken by Spirit, one of the Mars Exploration Rovers, is just another example of pareidolia, our ability to see patterns in random shapes.

As happens frequently, people tend to see faces or human forms in things like clouds, wood grain, and pancakes. This is only an optical illusion. If you need proof of this, for those of you in the US, look at one of the state-themed quarters from New Hampshire. There you can see the Man in the Mountain, a case of pareidolia that became an historic site (which has since crumbled.)

The photo shown here is the very large panoramic image from which a teeny, tiny rock formation was found that looks kind of human-like. Someone had to be looking really close to see it, as the rock formation is only about 6 centimeters high, and in the image you can also see a hill that’s over 8 kilometers (5 miles) away.

If you have any doubts in your mind that this is nothing more than just a very small, unusual rock formation, please, please, please see Emily Lakdawalla’s thorough explanation of the image at the Planetary Society’s website, which includes 3-D pictures that really make it clear this is not a humanoid. It’s a rock with a funny shape. And Phil the Bad Astronomer has more info on it as well here and here.

And, okay, here’s the really zoomed in image crop that has caused such a hubbub. Just remember how small this rock really is.
tiny detail from a panorama taken by the Mars Exploration Rover Spirit on sol 1,366-1,369 (November 6-9, 2007) of its position on the eastern edge of Home Plate. Credit: NASA / JPL / Cornell

Astronomers Could Detect Oceans on Extrasolar Planets

Imagine if astronomers could tell the difference between Earth-like extrasolar planets just by seeing the reflected light from their oceans? That sounds like science fiction, but a team of researchers have proposed that it’s really possible to detect the shape of the light curve glinting off an extrasolar planet and know if it has oceans.

This ground-breaking (water splashing?) idea was written in a recent journal article by D.M. Williams and E. Gaidos, entitled Detecting the Glint of Starlight on the Oceans of Distant Planets published January, 2008 in the Arxiv prepress e-Print archive.

The article describes the methods astronomers could use to detect the glint, or water reflection, from the “disk-averaged signal of an Earth-like planet in crescent phase.” They used the Earth as an example, and generated a series of light curves for a planet with our orientation and axial tilt.

They calculated that planets partially covered by water should appear much brighter when they’re near the crescent phase because light from the parent star reflects off the oceans very efficiently at just the right angles. By watching an extrasolar planet move through its orbit, its light curve should give off the telltale signature that there are oceans present.

According to their calculations, this method should work for about 50% of the visible planets. Furthermore, it should be possible to measure the ratio of land to water, and even get a sense of continents.

In order to test their theories, they’re planning to use remote observations of Earth, using interplanetary spacecraft. This will demonstrate if Earth can be observed at extreme phase angles—orbiting spacecraft around or on route to Mars.

And then the upcoming planet hunting missions, such as Darwin and the Terrestrial Planet Finder (if it ever gets completed) should be able to make the direct analysis of Earth-sized worlds orbiting other stars. Just by measuring the brightness, they should know if there are oceans, boosting the prospects for life.

Original Source: Arxiv