StarDate

Mars and Regulus


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Two fairly bright lights are headed for an especially close meet-up: the planet Mars and the star Regulus, the heart of the lion. They’re a few degrees apart tonight, but they’ll draw even closer over the coming evenings.

Right now, Mars and Regulus are almost the same brightness. One way to tell them apart is their color – Mars looks pale orange, while Regulus is white with a hint of blue. Binoculars accentuate the colors.

Another way to tell them apart is to look for them to twinkle. Regulus does, but Mars doesn’t. That’s because Mars is a bigger target in our sky.

Regulus is thousands of times the size of Mars. But it’s so far away that we see it as nothing more than a pinpoint. That tiny beam of light is bent and twisted as it passes through the atmosphere. That causes the star to “twinkle.” It twinkles more when the air is more unsettled.

Mars, on the other hand, is close enough that it appears as a tiny disk, made up of many pinpoints. Each one twinkles, but they even out. So Mars appears to hold steady as it shines through even the most un-steady skies.

Look for Mars and Regulus about a third of the way up the western sky at nightfall. Regulus perches to the left or upper left of Mars. They’ll pass closest to one another on Monday and Tuesday. After that, they’ll move apart. At the same time, Mars will fade. A couple of weeks from now, Regulus will clearly outshine the Red Planet.

Script by Damond Benningfield

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StarDateBy Billy Henry