Baptized in the fire of yesterday's total solar eclipse, a very young Moon emerges into the night sky.
Fresh from its brush with the sun during yesterday's total solar eclipse, the Moon waxes to a wiry crescent today (March 9th) and practically leaps into the evening sky.
For many skywatchers, this is an opportunity to spy a Moon younger than a day old. From the East Coast, the crescent will be just 21.5 hours past new; 22.5 hours for the Midwest; 23.5 hours for the mountain states; and 24.5 hours old viewed from the Pacific Coast.
While these times won't crack the record books, for many, seeing such an exceptionally thin Moon is thrill enough. The Moon's a rough place: boulder-strewn, no air, extreme temperatures, and riddled with more holes than the sign down the road. But somehow it appears tender and fragile when viewed as a crumbly crescent.
And I do mean crumbly. Shadows from mountain peaks and craters walls slice across the narrow Moon, giving it a broken, uneven appearance especially when viewed in binoculars.
Amateur astronomer and writer Stephen James O’Meara saw a thread-thin crescent only 15 hours and 32 minutes after new Moon in May 1990 using only his eyes. Mohsen Mirsaeed of Iran holds the record for youngest Moon seen with optical aid. He observed from a mountain site using giant 40×150 binoculars on September 7, 2002, and held the thinnest of crescents in view for one minute. At the time, the Moon was just 11 hours 40 minutes old and 7.5° from the Sun.
French amateur and astrophotographer Thierry Legault made the ultimate young Moon sighting when he captured a photo of the Moon at the instant it was new on July 13, 2013, using a sophisticated camera set-up. Although invisible to the naked eye and telescope at the time, his photos speak a thousand words.
Look for the slim March Moon starting about 15 to 20 minutes after sunset low in the western sky, where it stands about 5° high. That's not much for elevation, but provided the sky is haze-free, you should have no problem seeing this delicate creature. Low altitude and twilight may overwhelm the earthshine, the twice reflected sunlight from Earth that fills out the remainder of the Moon with a smoky fluorescence. Then again, maybe not. Binoculars should show it.
Spring's the best time for mid-northern observers to seek a young crescent Moon, for it's then that the ecliptic stands at its steepest angle to the horizon. Even though Wednesday night's Moon lies only about 13° from the Sun (a little more than one fist held at arm's length), that's almost all vertical distance directly above the setting Sun.
The situation is more dire in the fall, when the ecliptic reclines in the southwestern sky, making its shallowest angle to the horizon. Good luck finding a one-day Moon in October! Unless of course that happens to be this October. Not only will the moon be a few hours older and further from the Sun as seen from the central United States, it also lies a fair distance north of the ecliptic, extending its viewing time!
If the Moon were to stay put on the ecliptic this October and were the same age — 22.5 hours — as this month's crescent, it would scrape the horizon. Funny how the placement of the Moon's 5.1° inclination to Earth's orbit can really make a difference.
March brings back the saw-whet owls, the smell of earth, and drip of water. I always enjoy an excuse to get out. When going out involves a splinter Moon, all the better.