Let it Snow
A white Christmas is a popular image for the holiday season. Those of us in more southerly climes seldom get to see it, but we can always dream.
By now, though, snow may be falling around the Phoenix lander on Mars. The lander discovered snow falling from the Martian clouds back in September, and with the longer nights of autumn on Mars, the weather is getting colder.
Phoenix landed north of Mars's Arctic Circle in May. Its main mission was to study whether the northern plains are a suitable place for life. It quickly found frozen water beneath the surface, and it found that while the Martian soil wouldn't be great for life, it wouldn't be harmful, either.
Phoenix also carried a weather station. It measured temperatures, wind speed and direction, and humidity. It also used its cameras and a laser system to look for clouds, and to measure the dust in the air.
At first, clouds were scarce. By August, though, they were streaming across the sky. And in September, the lander detected snow. It vaporized before it hit the ground, but Phoenix continued looking for snowflakes around it.
By now, with little sunshine to supply its solar panels, the lander is out of power. And as the months roll by, water and carbon dioxide in the atmosphere will begin to condense around the lander -- some of it, perhaps, as snow. Eventually, Phoenix may be encased in ice -- a white landscape on the cold Red Planet.
Script by Damond Benningfield, Copyright 2008
For more skywatching tips, astronomy news, and much more, read StarDate magazine.