Mars lake was discovered using the MARSIS radar on board the "Mars Express" orbiter, and the profiles were collected between May 2012 and December 2015. The lake is centered at 193°E, 81°S, a flat area that does not exhibit any peculiar topographic characteristics. It is mostly surrounded by higher ground except on its eastern side, where there is a depression. Mars has two relatively small (compared to Earth's) natural moons, Phobos (about in diameter) and Deimos (about in diameter), which orbit close to the planet. Asteroid capture is a long-favored theory, but their origin remains uncertain. Both satellites were discovered in
A Beautiful Planet does not have a planetary magnetic field. Consequently, "its atmosphere was ripped away from the planet by the solar wind. If you could stand on Mars today, you would find a landscape of lifeless desolation; very cold, and very dry." One of the current challenges in maintaining Earth's planetary "life support system" is global warming. The film shows how Earth's warming climate is causing the Greenland ice sheet to melt, and drives the point home by showing the Jakobshavn Glacier calving an incredibly large number of icebergs in relatively rapid succession as the end of this flowing river of ice