The Moon is joined by some bright companions this week. They are well up in the south at nightfall and drop down the southwestern sky during the evening. One of those companions, Mars, has a close companion of its own, one of the brightest stars of Virgo. This view is at about 10 p.m.
Moon and Mars
[SFX: dust devil]
On the surface of Mars, this might be a common sound — the sound of a dust devil whirling past. These twisting columns of air and dust are common on the desert planet. Heated by the Sun, a column of air rises and spins. It picks up sand and carries it into the sky. An orbiting spacecraft recently photographed a dust devil that was 12 miles high — many times taller than the ones here on Earth.
No one has actually heard a Martian dust devil. But a team from the University of Southampton in England recently created some Mars sounds. Team members used knowledge of the Martian atmosphere and of the way sound moves to simulate what you’d hear on the Red Planet.
Mars’s atmosphere is less than one percent as dense as Earth’s. It’s much colder than Earth’s, and it’s made of a different mixture of gases. In that environment, sounds would be thinner and appear more distant than those here on Earth. Here, for example, is a comparison of a clap of thunder, first on Earth, then Mars: [SFX: thunder]
And here’s what a voice would sound like — again, first as it sounds on Earth, then Mars: [SFX: voice]
We won’t hear actual sounds from Mars for a long time. But we can appreciate the view of the planet. Tonight, it’s to the upper left of the Moon as darkness falls, and it sets by around 1 a.m. Mars looks like a bright orange star.
More about the Moon, Mars, and some other companions tomorrow.
Script by Damond Benningfield, Copyright 2012
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