London: Early in its history, Mars may have
a cold glacier-rimmed ocean covering its northern lowlands and
its coastline may have resembled that of Greenland or Norway,
according to a new study.
Scientists who conducted computer simulations of the Red
Planet found that there was a big temperature difference
between its warmer equatorial regions and the much colder
poles four billion years ago.
As a result, they believe, any ocean in the northern
lowlands would have been near-freezing, the Daily Mail
reported.
Lead researcher Dr Alberto Fairen of NASA`s Ames Research
Centre at Moffett Field, California, said if at all a ocean
existed in the Red Planet, it must have been very cold.
The researchers believe that a wall of glaciers skirting
the ocean would have prevented the deposition of
phyllosilicates originating in the equatorial highlands.
The minerals are associated with liquid water. Previously
their absence in the Martian northern lowlands cast doubt on
previous speculation that an ocean existed there.
Dr Fairen said: "We conclude that inefficient heat
transport from the equator to the poles on early Mars, due to
the absence of Earth-like equator-to-pole oceans, resulted in
a steep latitudinal gradient of temperatures in both
hemispheres, with warmer mid and equatorial areas, and glacial
polar regions.
"As a consequence, if a northern ocean existed on early
Mars, it was very cold. Glaciers rimming a cold northern ocean
would have prevented a significant fluvial transport of
phyllosilicate-rich materials from the highlands into the
lowlands."
The study is published in the journal Nature Geoscience.
PTI
