Incredible Mars Discoveries Made in 2021, From Water to Lava and Super Volcanoes

NASA's Perseverance Rover has detected bedrock on Mars that was probably formed by the flow of lava, coinciding with the ESA-Roscosmos ExoMars Trace Gas Orbiter (TGO) discovery of significant amounts of water beneath the Martian surface.

The findings cap off a significant year for humanity's scientific exploration of the Red Planet.

This has included the discovery of ancient lakes, which were literally bursting with water, thousands of volcanic eruptions that shook the Red Planet in its youth, and dust storms that may have stripped the planet of its water.

The Perseverance Rover: A Martian Rock Star

On December 15, NASA revealed that the Perseverance Rover had discovered crystals within the rock of the South Séítah region of the crater it roams around that showed the rock formed when crystals grew and settled in a slowly cooling magma.

"The rock was then altered by water several times, making it a treasure trove that will allow future scientists to date events in Jezero, better understand the period in which water was more common on its surface, and reveal the early history of the planet," Perseverance Project Scientist Ken Farley of Caltech said. "Mars Sample Return is going to have great stuff to choose from!"

This isn't the first time that the Perseverance Rover has made history since it landed on the surface of Mars in February of this year. In September, the rover drilled a rock core from a boulder in the Jezero crater, the first sample of this kind ever collected on an alien world.

Additionally, images captured by the rover this year allowed scientists to determine that the Jezero crater is indeed an ancient lake bed that billions of years ago had a river delta delivering water to it.

Furthermore, using images from the rover, scientists were able to ascertain that at points in the Jezero crater's history before Mars dried out over 3 billion years ago, it was subject to periods of flooding.

How Volcanic Eruptions and Lava Flow Shaped Mars

As previously reported by Newsweek, volcanic activity was also the subject of a study of Mars published in September. A team of NASA researchers discovered that 4 billion years ago thousands of volcanic "super-eruptions" shook the Red Planet.

These eruptions, described as "astonishingly powerful" by NASA, threw water vapor, carbon dioxide and sulfur dioxide high into the planet's atmosphere. This likely shaped the evolution of the planet's climate and atmosphere.

"Each one of these eruptions would have had a significant climate impact — maybe the released gas made the atmosphere thicker or blocked the sun and made the atmosphere colder," NASA geologist Patrick Whelley said. "Modelers of the Martian climate will have some work to do to try to understand the impact of the volcanoes."

The team made the discovery by observing giant holes on Mars called calderas, which can stretch dozens of miles. These form when a volcano collapses after a super-eruption.

Water on Mars

Also on December 15, ESA revealed that TGO, which it operates with the Russian space agency Roscosmos, had found significant amounts of water at the heart of the Martian canyon system, Valles Marineris.

Scientists have known for some time that water hasn't completely disappeared from Mars, but it is most commonly detected in freezing polar regions as ice.

This water discovered close to the surface of Mars seems to account for 40 percent of the near-surface material in the area TGO examined, which is about as large as the Netherlands.

"We found a central part of Valles Marineris to be packed full of water – far more water than we expected," Space Research Institute of the Russian Academy of Sciences researcher Alexey Malakhov, said. "This is very much like Earth's permafrost regions, where water ice permanently persists under dry soil because of the constant low temperatures."

Even this discovery of this hidden oasis is unlikely to change the view of Mars as a barren and arid world.

Currently, it isn't fully understood how Mars lost most of its water, but in August a paper published in Nature suggested that seasonal dust storms could have played a role in the process.

The authors of the study found that dust storms that occur every summer on Mars stop water that's carried to high altitudes from turning to ice. These water molecules are then vulnerable to being broken down into hydrogen and oxygen atoms by infrared radiation from the sun.

Hydrogen is the lightest element in the Universe and because of this, it's easily lost to space from the upper atmosphere of planets. This escape of hydrogen from Mars prevents water molecules from reforming and falling back to the surface.

Is the Best Yet to Come?

One thing that is notable by its absence from the discoveries from Mars made in 2021 is a sign that life once existed, or even still exists, on the Red Planet's surface.

But, with the increasing discovery that liquid water, a vital component of life, was once common on the surface of Mars, such a discovery may be tantalizingly close. Especially as the primary mission of the Perseverance Rover is to locate the signs of ancient life.

Perseverance's fellow rover Curiosity has recently pioneered a new trick to detect organic molecules that may signal the presence of life on Mars. While the first demonstration of this technique using a sample collected from a 22-mile long group of dark grey dunes in the Gale Crater turned up no evidence of organic molecules produced by life, it gives an exciting new weapon in the arsenal of Mars exploration.