ESA’s Trace Gas Orbiter (TGO) has spotted an ice-rich impact crater in Acidalia Planitia, a Martian plain between the Tharsis volcanic province and Arabia Terra to the north of Valles Marineris.
This image from ESA’s Trace Gas Orbiter shows a giant impact crater in Acidalia Planitia on Mars. Image credit: ESA / CaSSIS / CC BY-SA 3.0 IGO.
The ‘tree stump’ crater is located in the vast northern plains of Acidalia Planitia, centered at 51.9°N/326.7°E.
“This feature could easily be mistaken for a tree stump with characteristic concentric rings,” members of the TGO team said.
“It’s actually an impressive birds-eye view into an ice-rich impact crater on Mars.”
“Tree rings provide snapshots of Earth’s past climate and, although formed in a very different way, the patterns inside this crater reveal details of the Red Planet’s history, too.”
The interior of the ‘tree stump’ crater is filled with deposits that are probably water-ice rich.
“These deposits were laid down during an earlier time in Mars’ history when the inclination of the planet’s spin axis allowed water-ice deposits to form at lower latitudes than it does today,” the scientists said.
“Just like on Earth, Mars’ tilt gives rises to seasons, but unlike Earth its tilt has changed dramatically over long periods of time.”
“One of the notable features in the crater deposits is the presence of quasi-circular and polygonal patterns of fractures.”
“These features are likely a result of seasonal changes in temperature that cause cycles of expansion and contraction of the ice-rich material, eventually leading to the development of fractures.”
The image was taken by the CaSSIS camera onboard the TGO spacecraft on June 13, 2021.
“Understanding the history of water on Mars and if this once allowed life to flourish is at the heart of ESA’s ExoMars missions,” the researchers said.
“TGO arrived at Mars in 2016 and began its full science mission in 2018.”
“The spacecraft is not only returning spectacular images, but also providing the best ever inventory of the planet’s atmospheric gases with a particular emphasis on geologically and biologically important gases, and mapping the planet’s surface for water-rich locations.”
