A Beautiful Comet Passes By

A faint but beautiful comet passed by the Earth recently, and the accompanying picture shows you why so many of us love observing these icy visitors from deep space.

Called Comet Lovejoy (after its discoverer, Australian astronomy hobbyist, Terry Lovejoy), the comet passed closest to Earth on Jan. 7th. It wasn't that close -- 44 million miles away. That's why you really need a telescope to see the comet well.

But in a telescope, as you can see in our image, made by Austrian astro-photographer Gerald Rhemann, a beautiful coma and tail have already formed.  (As always, click on the picture to see a bigger version.)

Comets are chunks of ice (with dust frozen within them) left over from the formation of our solar system. Comet Lovejoy is estimated to be about 2 to 3 miles in diameter. But when the ice comes nearer to the Sun, as Comet Lovejoy is doing until it rounds the Sun January 30th, the Sun's heat and wind evaporates the comet's ice and releases the dust that has been locked up inside it for billions of years.

As a result, a cloud of evaporated material form around the comet. Called a "coma," the cloud around Lovejoy is already about 400,000 miles in diameter!

The Sun's energy and particles push material away from the coma, producing the long and twisting tail we see, stretching for millions of miles, always pointing opposite the Sun. The tail of the comet is very tenuous -- astronomers like to say that a "comet's tail is the closest thing to nothing that something can be and still be something."

After Comet Lovejoy leaves our neighborhood, we estimate it won't return to the inner solar system for more than 8,000 years. So enjoy it now. You can do a Google image search and see pictures from many other astronomical photographers around the globe. (Just to avoid confusion, we should mention that this is the fifth comet Mr. Lovejoy has discovered, and so there were other Comet Lovejoy's in the past. The official nerdy name for this comet is C/2014 Q2.)

If you have good binoculars or a telescope, observing instructions can be found at:
http://www.skyandtelescope.com/astronomy-news/observing-news/spot-comet-lovejoy-tonight-122920141/ 
or
http://www.universetoday.com/118031/if-you-can-find-orion-you-can-find-comet-lovejoy/ 

Comet PanSTARRS: Beware of the Internet Hype, but Check out the Sight

This coming week is perhaps the best time to look for a new comet in our evening skies, as long as your expectations are not set too high by some of the media attention it has received.   The comet – a chunk of ice and dirt from the distant backwaters of the solar system – is falling around the Sun with closest approach to our star on Sunday, March 10^th.  

For the next week, it will be visible very low on the horizon if you look toward the west.  Tuesday and Wednesday it will be near the crescent Moon and may be easier to spot as a result.  But here are the problems beginners will need to keep in mind:

1. It’s so low in the sky you will need to look for it from a location where you have a clear view all the way down to the western horizon -- and no hills, buildings, or trees in the way.  Out by the ocean is really great.

2. Things on the western horizon are SETTING – going quickly below the edge of the sky.  That means there is a very short window to see the comet.  Try too early, and the sky is too bright with sunlight.  Try too late, and the comet is below the horizon.  About 30 - 45 minutes after sunset is what experts are recommending.

3. If there are clouds or fog in the western direction, or you’ve got bright street or car lights in your view, the comet may be too hard to see.  In March, weather is an issue in many locations.

4. And the comet is so far from Earth, it is not spectacularly bright. In general, binoculars may be needed to pick the head of the comet and the faint upward-pointing tail out of the glow of the sunset.

Get the latest observing information at: http://www.skyandtelescope.com/observing/highlights/Spot-Comet-PanSTARRS-in-Twilight-196688441.html

By the way, if you are wondering about the strange name for a comet, it’s taken from the automated survey telescope in Hawaii that discovered it in 2011: the Panoramic Survey Telescope and Rapid Response System.