Universe Today
Get ready for an comet encounter of the extragalactic kind. In less than a week,
Comet PANSTARRS
will slide by the
Andromeda Galaxy
, the brightest galaxy visible in northern hemisphere skies. On and around that date, you'll be able to see them both glowing softly together in late evening and early morning twilight.
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The Andromeda Galaxy is the closest large galaxy to our Milky Way. It's easily visible in binoculars in the constellation Andromeda. Credit: Adam Evans[/caption]
Their apparent proximity if of course pure sleight of hand; the comet will be a mere 121 million miles (195 million km) from Earth on that date compared to Andromeda's 2.5 billion light years. For what it's worth, 121 million miles (195 million km) equates to 0.00002 light years. Let's just say they're WAY far apart in reality. Their juxtaposition will make for enjoyable binocular viewing as well as offer astrophotographers an opportunity to create a classic image.
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Comet PANSTARRS on March 22 photographed with a 200mm lens at dusk on a motorized tracking platform. Credit: Bob King[/caption]
Last night under the clearest of skies I easily found Comet C/2011 L4 PANSTARRS in the constellation Andromeda about 15 degrees above the horizon an hour after sunset. Twilight was still a factor as was the rising full moon. That's probably why the comet remained at the very limit of naked eye vision. Binoculars - I use 10x50s - clearly showed the comet's bright parabolic head and two degrees (four full diameters) of tail streaming up and to the right.
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Comet PANSTARRS shown every three days as it moves across Andromeda, passing near the Andromeda Galaxy around April 3. You can use Cassiopeia to point you to Beta Andromedae and from there to the comet. The map shows the sky facing northwest about one hour after sunset. Comet and galaxy brightness are exaggerated for the sake of illustration. Stellarium[/caption]
The comet has faded considerably since it first emerged into the evening twilight three weeks ago. Its head now shines around magnitude 3.5 and is noticeably fainter than the stars of the Big Dipper. As compensation, PANSTARRS is now easier to find, since it's both higher up in the sky and near a string of moderately bright stars in the constellation Andromeda.
PANSTARRS treks northward through Andromeda en route to the W of Cassiopeia in the next two weeks. It won't be long before the comet becomes circumpolar and remains visible all night long. The term refers to celestial objects that circle around the pole star without setting. The Big Dipper is the most familiar circumpolar constellation for much of the U.S. and Canada.
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Comet PANSTARRS in the early dawn sky during the first part of April. Once again, you can use Cassiopeia to help get you there. Don't forget binoculars! They're now essential to seeing the comet. The map shows the sky facing northeast about 75 minutes before sunrise. Stellarium[/caption]
On its journey to all-night visibility, PANSTARRS started pulling a double-shift this week. You can now see it both at dusk
and
at dawn. Although a bright moon will compromise the dawn view for a few days, you can watch for the comet low in the northeastern sky starting about hour and 15 minutes before sunrise. For the moment, it's about the same altitude above the horizon during both morning and evening hours. Evening is still preferred only because the bright moon has finally departed the sky during the hour or so the comet is visible.
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Jose Chambo's photo of Comet C/2011 L4 PANSTARRS from Spain on March 15 reveals a broad dust tail and narrower red-tinted tail. The red tail may be from sodium atoms released by materials colliding with each other as they jet off the comet's nucleus. Click image to see more photos. Credit: José J. Chambó[/caption]
Through my 15-inch telescope last night, PANSTARRS' head held a brilliant topaz gem - the
false nucleus
. This tiny ball of bright, fuzzy light contains the icy comet itself, hidden behind a fury of its own dust and vapor boiled off by the sun's heat.
Here's some additional images and videos of PANSTARRS that Universe Today has received from readers:
Zlatan Merakov created this timelapse from images he took on March 20 from Smolyan, Bulgaria.
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The view of Comet PANSTARRS L4 on 03-22-2013 over Warrenton, Virginia.
Modified Canon Rebel Xsi DSLR
30 second exposure, ISO 1600, University Optics 80mm F6 Refractor (600mm). Credit and copyright: John Chumack. [/caption]
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Comet C/2011 Pan-STARRS over Gradara Castle in Italy. Credit and copyright: Niki Giada. [/caption]