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Posted at 03:45 PM ET, 03/08/2013

Aloha! Comet Panstarrs: cosmic snowball to sneak above our horizon


This March 2, 2013 photo made available by spaceweather.com shows the comet, Pan-STARRS, seen from Queenstown, New Zealand. The recently discovered comet is closer than it's ever been to Earth, and stargazers in the Northern Hemisphere finally get to see it. (Minoru Yoneto - AP)

Nature rears back to pitch us a dirty, cosmic snowball: Comet Panstarrs, discovered from Hawaii, will likely sneak above our western horizon tonight or Saturday evening. It’s an apparition with an “Aloha!” flavor since to it we say, “hello and goodbye” rather fast.

Go hunt for Comet Panstarrs soon after sunset, but look low and look west. And we’re talking low – just a few degrees above the horizon at dusk.

Think fuzzy cotton ball with a tail against the early evening, dark heavens: Comet Panstarrs reaches perihelion – the closest approach to the sun – on Sunday March 10, and the best opportunity to see it likely will be from March 10 - 15.

Dances with comets: Take note that on the evening of March 13, the young, skinny crescent moon appears to sashay with our frozen friend into the western horizon.

Link: Viewing charts for the brightest period of the comet

If you can get away from the light pollution here in the Washington area, you may find comfort in the dark skies of western Maryland or Virginia Shenandoah region. Fred Espenak, scientist emeritus from NASA Goddard Space Flight Center, has suggested chasing the comet from automobile rest stops along Virginia’s Skyline Drive.

How bright will it be? Espenak thinks it could be as bright as second magnitude, which for a comet, could be bright enough to see from Washington. But, predictions vary among astronomers. Boldly, other astronomers suggest even brighter predictions, but these frozen, cosmic chunks of dirt and ice can be fickle.

Link: Fred Espenak’s noteworthy blog “Portal to the Universe”

After next week, the comet continues to loiter in our western, evening sky. As it rises higher and stays with us a little longer – before it dives into the western horizon – the comet continually dims on its retreat back into cosmos.

Watch: Fred Espenak’s night-by-night video for viewing Comet Panstarrs

Visibility Simulation of Comet Panstarrs (C/2011 L4) from Fred Espenak on Vimeo.

Looking for comets – and asteroids – in all the right places: Comets are named for their discoverers and this one was found in June 2011 by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) on Mount Haleakala, Maui, Hawaii. Thus, the comet is named Panstarrs. For all practicality, Pan-STARRS is a wide-field imaging facility at the University of Hawaii’s Institute for Astronomy. These folks help save our lives by combing the heavens daily looking for objects that could potentially hit Earth.

Link: The Pan-STARRS facility

As March marches from lion to lamb, Comet Panstarrs cosmically chugs along on a northward path, moving from the western sky to the west-northwest at dusk.

Link: An excellent overview of Comet Panstarr’s apparition (Rich Talcott, senior editor, Astronomy Magazine)

Watch: NASA’s Jet Propulsion Laboratory produced an excellent video explaining Comet Panstarrs:

Take note of the comet’s tail: In these early days, we’ll see it pointing south and by several days from now – as the comet travels away from the sun – it will likely be pointing in a northerly direction.

Astronomer Roy Gal, from the University of Hawaii, explains that comet composition is ice and dust. As they approach the sun, comets heat up and the ice begins to sublime – which is to change from ice into a gas. A comma develops, presenting a large envelope of gas and dust surrounding the solid comet nucleus.

Two tails develop: A dust tail and an ion tail made from gas molecules ionized by sunlight – and those tails may be over a million miles long, Gal says.

Another comet is on its way to our skies: Comet ISON – arrives this November. Right now, and it is predicted to be very bright and high in the sky.

By Blaine Friedlander  |  03:45 PM ET, 03/08/2013

Categories:  Latest, Astronomy, Space

 
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