Coming up this Saturday night, May 3, the fat crescent Moon will hover next to the famous blue star Regulus. As the brightest luminary in the entire zodiac and the main star of Leo the Lion, the ancient Persians considered it one of the “four royal stars.”
The Babylonians, 4,000 years ago, knew that only six bright stars could ever appear next to the Moon or planets. So when it happens, like it will do spectacularly this Saturday, it’s definitely worth a look.
It wasn’t always known as Regulus. In classical Roman times it was called Regia, meaning “the Royal One.” The Arabs called it Qalb, meaning “heart,” since it’s positioned in the lion’s chest. It took 2,000 years before Copernicus first coined the name Regulus.
Regulus is five times bigger than our Sun, with a sizzling hot temperature that prevents it from having the gaseous metals our own Sun possesses. Sitting a mere 85 light-years away, it’s one of our neighborhood stars, which is why it’s only slowly gliding farther away from us at the leisurely rate of two miles a second.
Seeing Regulus hovering just below the Moon is what catches our eye that night. But don’t neglect to also look to the Moon’s right, to the nearest star in that direction. That’s the planet Mars. Its orange color will be obvious, though some will probably be disappointed that it’s not very bright, and merely matches Regulus’ brilliance. That’s because Earth has been racing away from Mars since last fall at a hefty 66,000 mph, so it’s now on the far side of its orbit around the Sun, and almost as far away as it can get. Still, its ruddy hue, when contrasted with the Moon’s whiteness and the blue-white diamond color of Regulus, gives a colorful rebuttal to anyone who imagines that everything in the night sky is monochrome.
And if the time we choose to look up is 8:30 or 9 p.m., also take in the two brightest stars in the direction the Sun set, the west. This pair of stars is far more brilliant than all the others. The one on the right is the planet Jupiter, while on the left is blue-white Sirius, the famous Dog Star. A rewarding sky-snack this weekend, and the price is right.
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