Gully system on Devon Island [ltop] similar in morphology, scale, and context (they form preferentially along the cold, north-facing walls of valleys) to some of the recent gully systems reported on Mars [bottom].

Note from planetary scientist Pascal Lee with regard to an announcement made yesterday at NASA headquarters regarding a possible origin for gullies observed on Mars.

"The spacecraft data discussed by Phil Christensen is new and beautiful, but the interpretation of the martian gullies as resulting from the melting of snow and ice patches in response to obliquity (tilt) variations of Mars on timescales of 100,000 years or so is something my colleagues and I have proposed and published for the past three years.

Our model was proposed on the basis of terrestrial analog field studies we have conducted on Devon Island in the Canadian Arctic under the auspices of the NASA Haughton-Mars Project (www.marsonearth.org).

Bearing in mind that Mars is still a very mysterious place, we are happy that the data presented by Christensen seem to confirm our original interpretation and model."

References to our publications:

• "Snow and ice melt features on Devon Island, Nunavut, Arctic Canada as possible analogs for recent slope flow features on Mars", ( http://www.lpi.usra.edu/meetings/lpsc2001/pdf/1809.pdf ), Lunar and Planetary Science XXXII (2001)
• "Gullies on Mars: Clues to their formation timescale from possible analogs from Devon Island, Nunavut, Arctic Canada",( http://www.lpi.usra.edu/meetings/lpsc2002/pdf/2050.pdf ), Lunar and Planetary Science XXXIII (2002)

• "Mars: Always cold, sometimes wet?", ( http://www.lpi.usra.edu/meetings/lpsc2003/pdf/2127.pdf ), Lunar and Planetary Science XXXIV (2003) 2127.pdf

See also

• "Mars on Earth: The NASA Haughton-Mars Project", Ad Astra/SpaceRef, for an overview of activities on Devon Island.

Pascal Lee, Ph.D.
Planetary Scientist
SETI Institute & Mars Institute
NASA Ames Research Center, MS 245-3
Moffett Field, CA 94035-1000, USA
Tel:(408) 666-2001, Fax:(650) 604-6779
E-mail: pclee@earthlink.net

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