Late last month a team of Mars-watching astronomers sighted an immense cyclonic storm system raging near the Red Planet's north pole. 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. 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.
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