The object in question is a periodic comet called Comet Holmes (17P). On October 24th it brightened dramatically, by nearly a million times, and it did this virtually overnight. The comet erupted from a very dim magnitude 17, for no apparent reason, t to about magnitude 2.5. Within less than 24 hours, its star-like nucleus had expanded into a perfectly round, bright little disk visible in binoculars and telescopes. And tt looked like no comet ever seen before.

It's not the first time though that this comet has done something unprecedented. It also underwent a major eruption 115 years ago, in November 1892, when English amateur Edwin Holmes was the first to spot it. That time, it reached 4th or 5th magnitude, faded in the following weeks, and then brightened again two and a half months after the first outburst. There's more about the comet's history here.

Now, it seems, Comet Holmes has outdone itself. It lies in Perseus and will remain visible all night from most of the Northern Hemisphere. It's about 30° high — one-third of the way from the horizon to straight overhead — at 9 p.m. local daylight time. It then appears about twice as high as the bright star Capella. For observers at mid-northern latitudes, the comet climbs directly overhead between 2 and 3 a.m.

Unlike most bright comets, 17P/Holmes doesn't possess a long tail. It looks just like a modestly bright star, so you'll need to use the finder chart to zero in on it. Even large telescopes reveal no details. The comet is currently 150 million miles (245 million km) from Earth and 225 million miles (365 million km) from the Sun.

How long it will remain bright is anyone's guess, so take this opportunity to observe this very unusual comet.

Photographers, this amazing comet is an excellent target for off-the-shelf digital cameras and backyard telescopes. If you have any photos you'd like to submit (to be displayed on this page), send them to me at: nsosupport at gmail dot com. Include your name and a link to your website (if you have one).

Catch the Comet 17P/Holmes LIVE on SLOOH.com. The Slooh Observatory is located on Tenerife Island where A. Henriquez Santana first noticed 17P/Holmes’ outburst shortly after midnight on October 24. Snap your own picture of this comet in the Member Dome all week and see the astrophotos already captured by your fellow members on mySLOOH.com.