New clues of a watery past detected on Mars
While the search for life beyond Earth has taken us outside the Solar System with over 5,000 unique worlds already discovered, the candidate with the highest potential remains our next-door cosmic neighbour — Mars. The European Space Agency (ESA) has now found new clues that point to a watery past of the Red Planet.
The Mars Express has looked into Holden Basin, which is part of a series of channels and sinks called the Uzboi-Ladon-Morava (ULM) outflow where water once likely flowed. Scientists believe the water would have started in channels that drain into the Argyre Planitia, then flowed through Uzboi Vallis into the location now scarred by the Holden Crater.
Ladon Valles and Holden Crater, which are part of the basin, contain layered and phyllosilicate-bearing deposits, which are a type of mineral also found on Earth, with one example being clay.
Scientists believe that these could serve as a reaction center for organic molecules, which make up all living things on Earth, and past experiments suggest that phyllosilicates could have played a role in the origin of life.
This oblique perspective view of part of Mars' informally named Holden Basin was generated from the digital terrain model and the nadir and colour channels of the High Resolution Stereo Camera on ESA's Mars Express. (Photo: ESA)
The space agency released a series of detailed maps that show Mars' Grand Canyon, Valles Marineris, and the crater where water would have collected before streaming through Ladon Valles to Ladon Basin and beyond. It is worth mentioning that the names Holden Basin and Ladon Basin are not officially recognized by the International Astronomical Union.
"The complex history of the ULM outflow system makes it an interesting target to explore in more detail with Mars orbiters and rovers," ESA said in a statement.
The Holder Crater is nearly 140 kilometers wide and formed when Mars was hit by a space rock and is filled with material that was ejected from the massive strike. As the crater shows no evidence that significant amounts of water flowed through it, it very likely formed after the ULM system had mostly dried out.
"Due to its interesting geology and potential for clues to the past life, Holden Crater was on the shortlist of landing sites for NASA's Mars Science Laboratory and Perseverance rover," ESA said. However, the rover was later landed in the Jazero crater, where it has been collecting samples to be sent to Earth for deeper analysis as it continues to look for signs of ancient microbial life.