March 28th's Celestial Sandwich

If you're up in late evening on Thursday, March 28th, check out the brilliant, nearly full Moon and its two lovely attendants: the ringed planet Saturn and the icy-white star Spica.

Just about every night, after the 11 o'clock news and just before heading off to bed, I take a moment to walk outside and look up into the sky. If it's clear, there's always something worth seeing. Last Sunday, for example, I was greeted by the close pairing of a crescent Moon and Jupiter. Lovely, indeed!

Late on March 28th, the nearly full Moon is situated halfway between Saturn and Spica for observers in the Western Hemisphere.

Sky & Telesope diagram

If it's clear on the night of Thursday, March 28th, I'll be on the lookout (and you should too) for a just-past-full Moon perched midway between the icy-white star Spica to its upper right and creamy-hued Saturn to its lower left. This grouping won't be particularly tight — Saturn and Spica are currently 17° apart, about twice the width of your fist at arm's length — but it will still look nice.

This wide spacing actually helps you take in the trio. Ordinarily such a big, fat Moon would wash out anything in its vicinity. But Spica is no slouch: it's a 1st-magnitude blue giant. Saturn reaches opposition late next month, so it's already a half magnitude brighter than Spica. Look for the trio after 11 p.m., after they've had some time to clear the eastern horizon and are well up in the southeast.

Were I on the other side of the world (say, in Mumbai, India), the Moon would appear dramatically close to Spica on the 28th and just 3° from Saturn the next night. In fact, the Moon actually occults (covers up) Spica beginning around 13^h Universal Time as seen from much of southeast Asia and northern Australia. Details are available here.

For the rest of us, March 28th's celestial sandwich will simply be a nice moment to enjoy. Reflected sunlight takes about 1¼ seconds to reach us from the Moon's bleak, dusty surface. For Saturn, now just under 9 astronomical units (830 million miles) away, the travel time is 74 minutes. And the light from Spica, a star that shines 12,000 times brighter than our Sun, has been traveling about 260 years — since well before the American Revolution.