Red Planet Report

A regional dust storm currently swelling on Mars follows unusually closely on one that blossomed less than two weeks earlier and is now dissipating, as seen in daily global weather monitoring by NASA’s Mars Reconnaissance Orbiter.

Images from the orbiter’s wide-angle Mars Color Imager (MARCI) show each storm growing in the Acidalia area of northern Mars, then blowing southward and exploding to sizes bigger than the United States after reaching the southern hemisphere.

That development path is a common pattern for generating regional dust storms during spring and summer in Mars’ southern hemisphere, where it is now mid-summer.

“What’s unusual is we’re seeing a second one so soon after the first one,” said Mars meteorologist Bruce Cantor of Malin Space Science Systems, San Diego, which built and operates MARCI. “We’ve had orbiters watching weather patterns on Mars continuously for nearly two decades now, and many patterns are getting predictable, but just when we think we have Mars figured out, it throws us another surprise.” [More at link]

The major martian dust storm mentioned in the previous report gradually abated near the beginning of this past week. This left a large cloud of dust which stretched east to the region of southern Cimmeria. As the week progressed, the dust cloud slowly became less and less optically thick. Looking to the north, a few local-scale dust storms were spotted near Tempe and the Phlegra Montes. By the end of the week, an additional dust storm along the Acidalia storm-track became regional in size over Xanthe Terra. Equatorial water-ice clouds… [More at link, including video]