Low fog fills a Martian canyon in this artist's concept of future Martian exploration, while frost coats the canyon rim. A Mars-orbiting spacecraft is being retargeted to watch early mornings on the Red Planet to learn more about fog, low clouds, and frost observed by previous missions. [NASA]
Mars at Opposition II
Sunrise on Mars often sees frost and patches of fog and low clouds. They usually disappear by noon. But details of these cold, gray mornings remain unclear. How the fog and clouds form, and where and what times of year they’re most common are a bit...well, foggy.
A spacecraft may soon shine a little more light on those questions. It’s being moved to a new position that’ll allow it to view early morning conditions for half of each orbit around Mars. The maneuver began in February, but won’t be completed until November of next year.
Odyssey is the longest-operating Mars spacecraft — it arrived at the Red Planet in 2002. It orbits from pole to pole. It’s been synchronized so that for half of its orbit it’s seeing the ground at 4 to 5 p.m. local time. The other half of the orbit is before sunrise.
Sunrise conditions have received little attention from any Mars orbiter. A few observations by those orbiters — as well as from landers and rovers — show that morning frost, fog, and clouds are fairly common. Odyssey’s new orbit will allow scientists to study these conditions in much more detail — filling in some gaps in our knowledge of Martian weather.
And Mars is in spectacular view right now. It’s low in the east-southeast at nightfall, shining like a brilliant orange beacon. It scoots across the south during the night and is low in the west at dawn — if you can see it through the morning fog and clouds here on Earth.
Script by Damond Benningfield, Copyright 2014
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