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Morning Lineup

September 24, 2015

There’s an impressive lineup in the eastern sky at dawn tomorrow. Mars snuggles quite close to the star Regulus, while two brighter lights look on.

Mars and Regulus stand side by side, low in the east about an hour before sunrise. Mars is to the left of slightly brighter Regulus.

Seeing the two so close together really highlights the difference in their color. Mars shines pale orange — the color of the iron-rich dust that coats much of its surface. That color will become more obvious over the coming months as Mars moves closer to Earth, growing brighter as it does so.

Regulus, on the other hand, shines white — the color of the hot gas on its surface. The contrast with Mars, though, may make the star look slightly blue.

The planet Venus stands to the upper right of Mars and Regulus. It’s the brilliant “morning star,” so you can’t miss it. It looks almost pure white — the result of a blanket of clouds that hides the surface from view.

And the planet Jupiter stands about the same distance to the lower left of Mars and Regulus, quite low above the horizon. Only Venus outshines it, so it, too, is easy to pick out. Clouds cover Jupiter as well, in bands of tan, ivory, and similar colors. Seen from Earth, that gives Jupiter a slightly creamy color. And when it’s this low in the sky, it looks redder than usual, just as the rising Moon does.

So enjoy the subtle colors of this bright lineup, adorning the eastern sky at dawn.


Script by Damond Benningfield, Copyright 2015

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