About the SA Blog Network



Opinion, arguments & analyses from the editors of Scientific American
Observations HomeAboutContact

Naked-Eye Comet Pan-STARRS Climbing into Northern Skies

The views expressed are those of the author and are not necessarily those of Scientific American.

Email   PrintPrint

Comet Pan-STARRS (C/2011 L4)

Comet Pan-STARRS through a telescope. Credit: NASA

This year is shaping up to be a great one for amateur sky-watchers. Toward the end of 2013, astronomers expect the recently discovered Comet ISON (officially designated C/2012 S1) to shine mightily as it approaches the sun—possibly glowing as bright as the full moon. (Comets are unpredictable beasts, though, and often fail to meet the most optimistic predictions for their visibility.)

Before the main event, though, Comet Pan-STARRS should provide a nice warm-up act. Pan-STARRS (aka C/2011 L4) is already visible in the southern hemisphere, and will ease into northern skies in the coming days.

Westward viewing location of Comet Pan-STARRS at dusk. Credit: NASA

March 12 or 13 will likely provide the first good viewing opportunity in northern latitudes, as Comet Pan-STARRS lingers over the western horizon at dusk [see illustration at right]. The comet will be viewable with the naked eye as it climbs higher in the sky throughout March, according to predictions issued by the Paris Observatory. But binoculars are always useful to help make out a comet’s tail or coma (the fuzzy cloud of dust and gas surrounding the nucleus), the visible features that distinguish comets from less-adorned asteroids.

A word about the odd-sounding names “ISON” and “Pan-STARRS”: Comets are usually named for the astronomer or the observatory that discovered them (Hale-Bopp for Alan Hale and Thomas Bopp, to use a famous example*). The new comets were found at the ISON (International Scientific Optical Network) Observatory in Kislovodsk, Russia, and at the Pan-STARRS (Panoramic Survey Telescope and Rapid Response System) telescope in Hawaii, respectively.

A double feature of prominent comets is relatively rare. Comets as bright as Pan-STARRS only come along once every several years or so on average, comet researcher Karl Battams of the Naval Research Laboratory explained in an email. “Of course it is an inherently random process, as it appears we might get at least two comets like that this year,” Battams added. “Or so we hope, anyway!”

* CLARIFICATION (3/8/2013): The original text of this post cited the example of Edmond Halley and Halley’s Comet as an instance where a comet had been named for its discoverer. But as a reader noted on Twitter, Halley’s Comet was not strictly discovered by Edmond Halley. The comet had been spotted previously—numerous times over hundreds of years, in fact—but Halley recognized its periodicity and predicted its return.

About the Author: John Matson is an associate editor at Scientific American focusing on space, physics and mathematics. Follow on Twitter @jmtsn.

The views expressed are those of the author and are not necessarily those of Scientific American.

Rights & Permissions

Comments 8 Comments

Add Comment
  1. 1. Alta Astra 3:41 pm 03/7/2013

    How long will it be before some declares the new bright light in the heavens foretells the Second Coming? :)

    Link to this
  2. 2. American Muse 5:42 pm 03/7/2013

    How long before one hits us?

    Link to this
  3. 3. PeterT 6:04 pm 03/7/2013

    SA – Your e-mail this article DOES NOT WORK!!

    Link to this
  4. 4. Steven 9:29 pm 03/7/2013

    It seems like we’re having a lot of astronomical events, meteors, comets.
    Is there any possibility we’re in a binary star system and something is disturbing the Ort cloud, where most of the comets are, causing them to take an inner solar system orbit?

    Link to this
  5. 5. BobWalton 5:33 am 03/8/2013

    This is useful information for the Americas. Where will ISON be at our dusk in South Africa? We’re 6 hours ahead of you, so I guess it will be overhead?

    Link to this
  6. 6. BobWalton 5:37 am 03/8/2013

    Also, does it mean that people on your West coast won’t see it at all?

    Link to this
  7. 7. BobWalton 5:40 am 03/8/2013

    Sorry, I meant Comet Pan-STARRS.

    Link to this
  8. 8. SteveO 3:58 pm 03/11/2013

    Steve, don’t you think we would have noticed a near stellar neighbor? :)

    Usually Jupiter is blamed for perturbing those outer rocks, but of course there are largish dwarf planets out there. Still their gravity is so small it would need to be a pretty near miss to do much of anything, and they are tiny compared to the vastness of the Oort cloud. Not much chance of that.

    Stuff like this happens all the time, it is just perception bias that makes it seem unusual.

    Link to this

Add a Comment
You must sign in or register as a member to submit a comment.

More from Scientific American

Email this Article