University College, London | 2016 Aug 24
[img3="Perspective view of Aram Dorsum, an inverted channel on Mars and candidate landing site for the ExoMars rover. Credit: NASA/JPL/MSSS"]https://www.ucl.ac.uk/news/news-article ... orsum2.jpg[/img3][hr][/hr]Extensive systems of fossilised riverbeds have been discovered on an ancient region of the Martian surface, supporting the idea that the now cold and dry Red Planet had a warm and wet climate about four billion years ago, according to UCL-led research.
The study, published in Geology and funded by the Science & Technology Facilities Council and the UK Space Agency, identified over 17,000km of former river channels on a northern plain called Arabia Terra, providing further evidence of water once flowing on Mars. ...
Since the 1970s, scientists have identified valleys and channels on Mars which they think were carved out and eroded by rain and surface runoff, just like on Earth. Similar structures had not been seen on Arabia Terra until the team analysed high resolution imagery from NASA’s Mars Reconnaissance Orbiter (MRO) spacecraft.
The new study examined images covering an area roughly the size of Brazil at a much higher resolution than was previously possible – six metres per pixel compared to 100 metres per pixel. While a few valleys were identified, the team revealed the existence of many systems of fossilised riverbeds which are visible as inverted channels spread across the Arabia Terra plain. ...
Extensive Noachian Fluvial Systems in Arabia Terra:
Implications for Early Martian Climate - J.M. Davis et al
- Geology (online Aug 2016) DOI: 10.1130/G38247.1 (pdf)