Wow! Striking Green Comet Suddenly Visible in Evening Sky

By Aussiegirl

Wow is right! I remember vividly being able to see comet Hale-Bopp with the naked eye a number of years ago. That was quite exciting since not much else is really visible in the brightly lit suburban area right outside Washington. It was stunning, and appeared to have two tails, rather than one. There's always something mysterious about the color green -- perhaps this is where the little green men come from, or maybe it's a piece of the moon, which has been said to be made of green cheese. And it has such a romantic name -- Comet Swan -- so much nicer than Hale-Bopp.

SPACE.com -- Wow! Striking Green Comet Suddenly Visible in Evening Sky

What had been a modest comet seen only with binoculars or telescopes flared up this week to become visible to the naked eye [images].

Comet SWAN, as it is called, is in the western sky after sunset from the Northern Hemisphere. It remains faint, likely not easy to find under bright city lights but pretty simple to spot from the countryside.

It is a "fairly easy naked-eye comet," said Pete Lawrence, who photographed the comet from the UK. "The tail is now showing some interesting features too."

UPDATE: Late Thursday, however, Lawrence reported that the comet already may be getting dimmer. It is not clear what skywatchers should expect of this comet.

Find it

The comet, also catalogued as C/2006 M4, is about halfway up in the sky in the direction of the constellation Corona Borealis [Sky Map].

As with most comets, this one looks like a fuzzy star. It has an interesting green tint, however, indicating it has a lot of the poisonous gas cyanogen and diatomic carbon, astronomers say.

Sam Storch, a long-time sky watcher from Long Island, NY, said the comet appears "quite a bit deeper than any other green I have seen in any sky object, even planetary nebulae."

"Comet SWAN is very easy to find," said Joe Rao, SPACE.com's Skywatching Columnist. "In good binoculars it appears as a bright, symmetrical and surprisingly green blob."