Friday 5th November 2021 BRLSI Zoom lecture delivered from California

Mars: Ancient rivers, lakes and oceans. But where is the water now?

Michael Carr
Leader of the Imaging Team for NASA on the Viking Orbiter and subsequent missions.

Image credit: (c) NASA/THEMIS

The history of water on Mars has huge implications for the possibility of life on Mars and the future of life on Earth. This is the first of two lectures on this subject, with the second lecture to be given by Steve Clifford in February.

Widespread fluvial dissection of the heavily cratered martian highlands indicates that, around 3.8 billion years ago, Mars had a warm, wet, Earth-like hydrologic system with precipitation, rivers, lakes and oceans. Mars then cooled and developed a kilometers-thick permafrost. Around 3.0-3.4 billion years ago massive eruptions of groundwater trapped beneath the permafrost caused huge floods that flowed into the low-lying northern plains to create an ocean that rapidly froze. The water subsequently sublimated away, some to form the present polar caps but most being lost to space, mainly during periods of high obliquity.

Michael Carr received a BSc from University College, London in 1956 and a Ph.D from Yale in 1960, both in Geology. After a postdoc at the University of Western Ontario he joined the U.S. Geological Survey in 1962. He first started working on Mars in 1970, after joining the Mariner-9 imaging team. Subsequently, between 1976 and 1980, as leader of the Viking Orbiter Imaging team, he supervised the acquisition of 55,000 images of Mars. He was also involved with every following Mars mission until he retired in 2004. He has written over 200 papers on Mars and three books, The Surface of Mars (1981), Water on Mars (1996) and The Surface of Mars (2006). He lives in Woodside, California.

This talk was given remotely from California and it was planned to be available either remotely on Zoom or at the BRLSI where it would have been projected.  In fact it was online on Zoom only.

The video recording of this lecture is now freely available on the Virtual BRLSI YouTube channel. Please go the following link to view it.