Posted: Thu, Jan 18, 2001, 12:02 AM ET (0502 GMT)
Ice streams, and not flowing water, may have created many of the channels seen on the surface of present-day Mars, according to research announced this week. Baerbel Lucchitta of the USGS found that channels in one region of Mars shared a number of key characteristics with channels created by ice streams flowing under the icy surface of Antarctica and into the surrounding ocean. The shape of the "islands" created as the material moved around obstructions, the location of the channels below a hypothesized sea level, and portions of the channels where material appeared to flow uphill all argued for ice, and not water, as the material that formed the channels on Mars, she concluded. Lucchitta believes the ice streams flowed into an ocean that covered much of the planet's northern hemisphere, and where today is only a low-lying plain. Ice might still exist in these ares, covered by dust layers; instruments like a ground-penetrating radar on ESA's Mars Express mission might be able to detect such ice if it is not too deep.

Related Links:

•  American Geophysical Union press release