Magnetic tornadoes could liberate Mercury's tenuous atmosphere
Tuesday, June 2, 2009 - 10:42
in Astronomy & Space
As the closest planet to the sun, Mercury is scorching hot, with daytime temperatures of more than 800 degrees Fahrenheit (approximately 450 degrees Celsius). It is also the smallest rocky planet, so its gravity is weak, only about 38 percent of Earth's. These conditions make it hard for the planet to hold on to its atmosphere, which is extremely thin, and invisible to the human eye.