Comet SWAN Brightens Significantly

Until today I hadn’t been able to observe the comet SWAN since the 12th of October because of the Irish weather. The last time I observed it the comet was rather low in the sky and easily visible in binoculars but definitely not a naked-eye object. Today I managed to observe the comet again twice, once before the sky was fully dark and then again when it was properly dark. The comet has moved significantly and is now a lot higher in the sky in the constellation of Hercules but what really struck me was how much it had brightened.

[tags]Comet, SWAN[/tags]

SWAN is now almost in the same binocular field of view as M13 and is significantly brighter than it. I’m not great at estimating magnitudes but I’d estimate the comet’s brightness at being between one and two magnitudes brighter than M13. To tie down the magnitude a bit better I looked for a star in the same filed of view as the comet that was the same brightness when unfocused to the same size as the comet. I found an almost perfect match, the brightest of a near straight line of stars a little to the east of the comet. When I got home I checked Equinox which showed the star to be SAO 65108 which is magnitude 4.7. Based on the comparison with this star and with M13 I’d say the comet is about magnitude 4.5. I couldn’t see it with the naked eye from Maynooth but I’m putting that down to a combination of poor seeing and light-pollution. I’d be quite confident that it would be a naked-eye object from a dark observing site on a clear night.

This comet is definitely worth keeping a close eye on over the next few days before the moon spoils the show. You can get a finder chart and the orbital elements for the comet here.