In astronomical circles the year 2013 has been dubbed the "Year of the Comets" and for good reason. Already there are three comets that should easily reach naked eye visibility at various times this year. Of these, Comet ISON (C/2012 S1) is predicted to be spectacular, a possible daylight comet. However, we have to wait sometime before Comet ISON graces our skies; it's predicted to reach peak brightness around November. In the meantime, Comet PanSTARRS (C/2011 L4) along with Comet Lemmon (C/2012 F6) are already showing in the southern sky.

Based on initial predictions, PanSTARRS was expected to be a great comet of magnitude -1 in early March 2013. Although it had been brightening as expected until the end of last year, the brightening noticeably slowed down in January and therefore unfortunately, PanSTARRS is likely to fall short of the target. How far short, nobody knows but new predictions have the comet peaking at around 2nd magnitude. Of course, such is the unpredictability of these Oort cloud objects that it is impossible to exactly say what might happen next. The comet could easily be a complete damp squid, more likely to put on a reasonable show, but may just suddenly burst back into life again and dazzle audiences! Whatever happens, PanSTARRS remains on target to be a naked eye object and worth watching out for as it certainly going to be interesting.

Comet PanSTARRS recent observations

On January 1st, PanSTARRS was at magnitude 8.3 and only about 0.4 magnitudes fainter than predicted. At this time, the comet displayed a small coma of the order of 2 arc minutes in diameter. By January 7th, PanSTARRS had brightened slightly to magnitude 8.0 and the coma up to 3 arc minutes in diameter, but now 0.8 magnitudes fainter than hoped. A week later the comet was up to magnitude 7.3 and now a much easier binocular target with a 5 arc minutes coma. The nucleus was bright with a diffuse and fainter outer coma, which appeared circular with just a hint of elongation. It was thought by the end of January the comet would be now a naked eye target at about magnitude 5.5. Unfortunately, although relatively easy to spot with binoculars, it had only brightened to magnitude 7.0 and now 1.5 magnitudes fainter than originally predicted. Based on the latest information, PanSTARRS should now be a naked eye object in the middle of February before peaking at around magnitude 2.0 on March 10th.

Location, magnitude and star chart

PanSTARRS has been traveling the southern section of the sky and will continue to do so until March 11th when it will move into the northern part of the sky. On February 1st, the comet is located in obscure constellation of Telescopium with a declination of 45 degrees south, and visible only to those who live in southern and tropical latitudes. On this date, it is positioned 1.5 degrees south of double star Beta (β) Sgr, in the constellation Sagittarius. The Bayer designation Beta Sgr is shared by two star systems, Beta 1 (β ¹) Sgr and Beta 2 (β ²) Sgr. They have magnitudes of 4.0 and 4.3 respectively. From latitude 30 degrees south (the approximate position of Santiago, Cape Town, Perth and Sydney) the comet will stand about 15 degrees above the southeastern horizon 45 minutes before sunrise and will remain low above the horizon until about the middle of the month. For northern hemisphere observers, the comet will remain invisible throughout February and they will have to wait until mid-March to catch their first glimpse of it.

The charts below show the position of PanSTARRS until February 17, 2013.

Finder Chart for Comet PanSTARRS from December 14, 2012 to January 31, 2013 - pdf format

Finder Chart for Comet PanSTARRS from January 26, 2013 to February 17, 2013 - pdf format

Summary

Predicted to be one of the great comets of recent times, comet PanSTARRS (C/2011 L4) was expected to reach magnitude -1 during the early part of March 2013. Up until the start of the New Year, it was living up to expectations. The comet was brightening as expected and looking good to put on a great performance. But then in January the bad news arrived, the comet failed to brighten up as fast as predicted and now looks like peaking at only around magnitude 2.0. Nevertheless, we should have the experience of a naked eye comet visible in the sky.

Comet PanSTARRS

Comet PanSTARRS (C/2011 L4) Data Table

See also

Final swan song for Comet PanSTARRS (C/2011 L4)
Comet PanSTARRS (C/2011 L4) heads towards a close pass by of Polaris, the Northern Pole Star
Comet PanSTARRS (C/2011 L4) moves through Cassiopeia
Comet PanSTARRS (C/2011 L4) starts to fade but remains a naked eye and binocular target
Media Frenzy as Comet PanSTARRS (C/2011 L4) is now visible to observers in the Northern Hemisphere
How to see Comet PanSTARRS (C/2011 L4) in March 2013
Comet PanSTARRS (C/2011 L4) edges closer to March evening performance
Comet PanSTARRS (C/2011 L4) brightens to within binocular range