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A Bright Green 'Christmas Comet' Will Fly the Closest To Earth In Centuries
On Sunday night, a comet that orbits between Jupiter and the sun will make its closest approach to Earth in centuries. According to Tony Farnham, a research scientist in the astronomy department at the University of Maryland, the comet will appear as a bright, fuzzy ball with a greenish-gray tint. "You've got a one-kilometer solid nuclear in the middle, and gas is going out hundreds of thousands of miles," says Tony. The comet glows green because the gases emit light in green wavelengths. The New York Times reports: The ball of gas and dust, sometimes referred to as the "Christmas comet," was named 46P/Wirtanen, after the astronomer Carl Wirtanen, who discovered it in 1948. It orbits the sun once every 5.4 years, passing by Earth approximately every 11 years, but its distance varies and it is rarely this close. As the comet passes by, it will be 30 times farther from Earth than the moon, NASA said. The proximity of 46P/Wirtanen provides an opportunity to research the tail of the comet and see farther into the nucleus.
The comet is visible now but it will shine even brighter on Sunday as it reaches its closest approach, 7.1 million miles from Earth. That may sound really far, but it is among the 10 closest approaches by a comet in 70 years, NASA said. Only a few of those could be seen with the naked eye. Don't worry if you miss the comet on Sunday. It should be just as visible for a week or two because its appearance will change gradually. After it moves on, it won't be this close to Earth again for hundreds, if not thousands, of years. Online charts can help pinpoint its location.
The comet is visible now but it will shine even brighter on Sunday as it reaches its closest approach, 7.1 million miles from Earth. That may sound really far, but it is among the 10 closest approaches by a comet in 70 years, NASA said. Only a few of those could be seen with the naked eye. Don't worry if you miss the comet on Sunday. It should be just as visible for a week or two because its appearance will change gradually. After it moves on, it won't be this close to Earth again for hundreds, if not thousands, of years. Online charts can help pinpoint its location.
Maybe on say Friday ?
Oh well people will still get to see the comet.
Doesn't name the constellations. In fact it's difficult to even see the constellations on it. Try this chart from Sky and Telescope. The comet is currently between Taurus and the Pleiades. Most occasional stargazers can locate those.
Don't expect much though. It's currently at its peak magnitude of 3.9. Magnitude 6.0 is the dimmest you can see in dark skies, with most visible stars falling between -1.5 and +5. You're not going to see it with the naked eye from a city. Maybe a fuzzy blob with decent binoculars. The closest bright star is Aldebaran, which at magnitude 1 is about 15x brighter.
It's magnitude 8.8. Nobody's going to see it with their naked eye - the limit there is about M6.7. GoSkyWatch and a decent set of 50mm binoculars should do the trick.
Without looking up some details, here are a couple of answers. The "P" means it is a periodic comet - one of the relatively few which have had an orbit determined. Comets originate way out on the edge of the solar system and many of them discovered have never been seen before and when they return to way out there, never will be again. The periodic comets have had their orbit perturbed by a planet at some time in the past and are in much smaller orbits with periods measured in tens of years (maybe hundreds) instead of tens of thousands. This comet 46P/Wirtanen has a relatively short orbital period of 5.4 years. The "46" means it is the 46th comet to have been assigned by the astronomical community as periodic. Discovered in 1948 and it is only the 46th determined periodic comet -- shows there are not many of them. The first assigned periodic comet is Halley's comet, now designated, 1P/Halley.