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More Moon and Companions

July 14, 2016

The Moon anchors a rectangle of bright heavenly bodies tonight. The other points of the box are the planets Mars and Saturn and the star Antares, the heart of the scorpion.

That order describes the brightness of the four objects, as well as their relative distances from Earth. And there’s a direct correlation between the two.

The Moon looks brighter than the other three only because it’s our closest neighbor — just a quarter of a million miles away. The lunar surface is actually quite dark. But because the Moon is so close, it forms a big target in the night sky, and a lot of its light shines our way.

Mars stands below or to the lower right of the Moon as night falls, and looks like an orange star. It’s not a star at all, though. Instead, it’s a planet — and a close one at that. Earth passed closest to it just a couple of months ago, so it’s still a big target.

Saturn stands farther to the lower left of the Moon, and looks like a golden star. It’s the second-largest planet in the solar system, and its clouds reflect a lot of sunlight. But Saturn is hundreds of millions of miles away, so it looks fainter than Mars.

Antares is the faintest member of the rectangle, to the lower right of Saturn. But it only looks faint. In reality, it’s a supergiant star — billions of times brighter than the Moon and planets. But it’s hundreds of light-years away — a distance that dulls its magnificence.

More about the Moon and Saturn tomorrow.

Script by Damond Benningfield

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