Cyclone on Mars
Credit:
J. Bell (Cornell),
S. Lee (Univ. Colorado),
M. Wolff (SSI), et al.,
NASA
Late last month a team of
Mars-watching astronomers sighted an immense
cyclonic storm system raging near
the Red Planet's north pole.
Their discovery picture, made with the Hubble Space Telescope
on April 27, is seen at left while the projected insets
(right) show closeups of the storm and surrounding areas.
Shrunken to its
martian
midsummer state,
Mars' north polar cap
appears at the top of the discovery picture.
The polar cap is
clearly smaller than the storm just below it and farther left.
Similar to the
"spiral storms" detected on Mars over 20 years ago by
the Viking spacecraft, this storm was marked by a system of swirling
bright water-ice clouds instead of the billowing dust of a more typical
martian wind storm.
Measuring roughly 1,000 miles across,
with a cloud-free central eye spanning about 200 miles, it
was comparable in size to
cyclones seen in
planet Earth's polar regions.
The storm system was imaged once more, hours later, but then
was not seen again and may have had a lifetime of
only a few days.