NASA: Past Life on Mars

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  In its ancient past, Mars likely contained many of the necessarily ingredients for microbial life to flourish on its surface.
• Now, a new discovery by NASA’s Perseverance rover shows a trifecta of compelling evidence—including the presence of water, organic compounds, and a chemical energy source—all on one rock located in the Jezero Crater.
• Although this is the best clue yet that microbial life existed on Mars, there are still other explanations that could explain this geologic display without the existence of microbes.

“Is there life on Mars” is a question that has vexed astrobiologists and David Bowie alike. While the latter imagined some macabre collection of arachnids on the Red Planet, NASA scientists are fixated on finding evidence that microbial life once flourished on the fourth rock from the Sun. So fixated, in fact, that the space agency has spent more than $5 billion getting two immensely complicated robotic rovers—Curiosity and Perseverance—onto the Martian surface with this specific microbial mission in mind.     READ MORE...

TWENTY-TWO People Needed to Colonize Mars

Researchers estimated that as few as 22 people would be needed to sustain a colony on Mars. But there are lots of caveats, and the new study largely misses the point of colonizing the Red Planet in the first place, experts say.

Only 22 people are needed to create a colony on Mars, an optimistic new study suggests. However, not everyone agrees, and some experts think many more people would be needed to create a lasting human presence on the Red Planet.

In the study, which was uploaded to the pre-print database arXiv on Aug. 11 and has not been peer-reviewed, researchers used a computer program, known as an agent-based model (ABM), to predict how many people would be needed to sustain a colony on Mars. ABMs simulate how well groups react to challenging scenarios based on their personality types.

The model looked at four personality types: agreeables, who are not very competitive or aggressive; socials, who are extroverted and do well in social settings; reactives, who struggle to deal with changes to routine; and neurotics, who are highly competitive and aggressive. The model then varied the number of each type when doing key tasks such as Martian mining and farming.

The researchers found that iIf most people were agreeables or socials, just 22 people could sustain a colony. With more neurotics and reactives, larger groups were needed to succeed.

Limiting the size of the first Martian colonies will be very important, because the more people and equipment that are needed, the more expensive it will be.    READ MORE...

Death Spiraling Moon

Mars' moon Phobos crosses the face of the sun, captured by NASA’s Perseverance rover with its Mastcam-Z camera. The faint black specks to the bottom left are sunspots. 

(Image credit: NASA/JPL-Caltech/ASU/MSSS/SSI)

NASA’s Perseverance rover has captured the clearest ever footage of a solar eclipse over Mars, and the results are out of this world.

The rover snapped the ethereal video of Mars’ potato-shaped moon, Phobos, moving across the face of the sun on April 2. During the eclipse, Phobos projected its uneven shadow over the Martian surface — appearing almost as though it was the pupil of a gigantic eyeball rolling in its socket.

Perseverance recorded the footage midway through its journey to a river delta on Mars’ 28-mile-wide (45 kilometers) Jezero Crater, where it will search for evidence of life on the Red Planet. Training its state-of-the-art Mastcam-Z camera on the sky, the rover recorded the misshapen moon’s solar transit with the greatest zoom and at the highest framerate ever.

"I knew it was going to be good, but I didn't expect it to be this amazing," Rachel Howson, a mission operations specialist at Malin Space Science Systems and one of the Mastcam-Z team members who operates the camera, said in a statement.

Phobos, named after the Greek god of fear, is roughly 157 times smaller than Earth's moon and is one of Mars' two natural satellites, alongside the even smaller Deimos (whose name comes from the Greek god of dread).

Scientists believe that the brother moons were once roaming asteroids that were snared into Mars’ orbit by the planet’s gravitational field. The orbits of these captive asteroids are unstable, according to researchers, and scientists predict that in a few tens of millions of years' time Deimos will spin out into space while Phobos will slam into Mars’ surface.  READ MORE...

Martian Caves Offer Protection

Cave Entrance

There are very good reasons why Mars is such a desolate, barren landscape. With no thick atmosphere nor a magnetic field, the Red Planet’s surface is bombarded daily by radiation up to 900 times higher than seen on Earth. However, some places are sheltered. New research has found that cave entrances are shielded from the harmful radiation that normally hits Mars. This may make them ideal as both sites for future settlements and robotic missions meant to scour for signs of alien life.

Despite amazing advances in space exploration in the last decade, if we’re going to take the idea of settling Mars sometime during this century seriously, there are many challenges that need to be overcome. That’s unless we’re content with one-way suicide missions.

There’s no shortage of environmental hazards out to kill any astronaut bold enough to dare set foot on Mars. For one, the planet only has 0.7% of Earth’s sea-level pressure, meaning any human on Mars must wear a full pressure suit or stay barricaded inside a pressure-controlled chamber, otherwise oxygen wouldn’t flow through the bloodstream and the body could swell and bleed out.

Then there’s the issue of radiation. Mars is farther away from the Sun than Earth, receiving roughly 60% of the power per square meter seen on a similar site on Earth. But since Mars doesn’t have a magnetic field to deflect energetic particles, coupled with the paper-thin atmosphere, its surface is exposed to much higher levels of radiation than Earth. Furthermore, besides regular exposure to cosmic rays and solar wind, it receives occasional, lethal radiation blasts due to strong solar flares.

Measurements performed by the Mars Odyssey probe suggest that ongoing radiation levels on Mars are at least 2.5 times higher than what astronauts experience on the International Space Station. That’s about 22 millirads per day, which works out to 8000 millirads (8 rads) per year. For comparison, the people in the U.S. are exposed to roughly 0.62 rads/year on average.  READ MORE

China's Zhurong Mars Rover

China's Zhurong rover has quietly clocked up 1,900 feet (585 meters) of driving on Mars and has been using its science instruments to check out nearby geologic features in Utopia Planitia.

Zhurong's latest exploits have seen it analyze dunes amid the local rocky Martian terrain and visit the backshell and parachute that helped the rover land safely on the Red Planet.

A new release by the China National Space Administration on July 23, also marking the first anniversary of the launch of China's Tianwen-1 Mars mission, showed Zhurong had visited a second wind-formed sand dune.

The rover used its surface composition detectors, multi-spectral cameras and other science payloads to analyze the formation, according to the update.

Zhurong landed on Mars in May and rolled onto the surface a week later, making China just the second country after the United States to land and operate a rover on Mars. The rover's first feat was driving away from the lander, dropping a small, remote camera, and returning to pose with the lander for an epic selfie.

Later updates have included remarkable roving footage as well as sounds captured by the rover's climate station.

The solar-powered rover has since been making its way south of the landing site. The CNSA released a map showing Zhurong's travels up to July 21 and covering 66 Mars days, or sols. Both Zhurong's parent orbiter, Tianwen-1, and NASA's Mars Reconnaissance Orbiter have also been monitoring the journey.

Past Life on Mars

Evidence of ancient life may have been scrubbed from parts of Mars, a new NASA study has found.

The space agency's Curiosity rover made the surprising discovery while investigating clay-rich sedimentary rocks around its landing site in Gale Crater, a former lake that was made when an asteroid struck the Red Planet roughly 3.6 billion years ago.

Clay is a good signpost towards evidence of life because it's usually created when rocky minerals weather away and rot after contact with water — a key ingredient for life. It is also an excellent material for storing microbial fossils.

But when Curiosity took two samples of ancient mudstone, a sedimentary rock containing clay, from patches of the dried-out lake bed, dated to the same time and place (3.5 billion years ago and just 400m apart), researchers found that one patch contained only half the expected amount of clay minerals. 

Instead, that patch held a greater quantity of iron oxides, the compounds that give Mars its rusty hue.  TO READ MORE