Over the next three nights, skywatchers should expect their best views yet of Comet Lulin. It makes its closest approach to Earth — some 38 million miles away — on Tuesday, Feb. 24.
To the naked eye, the comet looks like a fuzzy patch of hazy light against the night sky. Use binoculars or telescopes, and you’ll be able to pick out its brighter center, along with its dual tail — a brighter tail of dust, and a dimmer one of ionized gases the comet sheds as its sun-warmed ices change directly from a solid to a gas.
Lulin, formally known as C/2007 N3, will dim quickly through March, thanks to the kick it’s gotten from the sun’s gravity. Then it’s Oort-a here — heading back out to its kin in the Oort Cloud, a vast collection of icy construction debris left over from the formation of the solar system some 4.6 billion years ago.
Comet Lulin will make its closest approach to Earth on Monday night. The circled X shows the comet's position at seen from Boston at 10 p.m. local time. It appears in the southeastern sky near Saturn, at the tip of Leo the Lion's hind leg.