Even if you don’t have a telescope, you can still enjoy the photo of two-tailed wonder Comet K1 PANSTARRS passing the Whirlpool Galaxy a few nights ago. The shorter tail is made of dust boiled off the comet’s nucleus by the sun’s heat; the long, dangling ion tail of gases that glow when energized by the sun’s ultraviolet light.
We see the dust tail for the same reason you can see dust floating in a sunbeam coming through your window – it’s an excellent reflector of sunlight. Tails can grow to many millions of miles long and give comets their special visual appeal. The longest measured belonged to Comet Hyakutake which swung by Earth in 1996 with a dust tailed over 310 million miles (500 million km) long!
Don’t be fooled though by these big numbers. There’s so little material in comet tails I once read you could pack it into a single suitcase if you had a big enough vacuum cleaner to gather it up. Let’s just say you get a lot of bang for your buck with these small, icy bodies.
Comet K1 PANSTARRS was discovered by the PANSTARRS-1 survey telescope atop Haleakala Crater on Maui, Hawaii in May 1982. Only in the past few months has it brightened enough to see in smaller telescopes. Observers with scopes 6-inches and up should find the comet easily enough especially since it’s traversing the familiar constellation of Ursa Major the Great Bear not far from the Bowl of the Big Dipper.
Two nights ago I even found it in 50mm binoculars from a dark sky where it looked like a faint, smoky smudge of light. Try it yourself – you might be surprised. Currently at magnitude 9, PANSTARRS K1 has been gradually brightening week by week. Come autumn, it should be obvious in binoculars at magnitude 6. Observers with dark skies might even see it with the naked eye.
Now through about June 20 K1 will be well-placed for skywatchers in mid-northern latitudes. While brightest in fall, it will be very low in the morning sky shortly before dawn, so look for it soon if you can.
Through the scope, the comet shows a cottonball-like coma with a bright, starlike nucleus and short, fat tail pointing southeast.
The moon is returning to the evening sky, but before it’s too bright, take a look the next few nights. Dark, moonless skies return again beginning around May 16. Good luck!