September 20, 2017

Faint Fuzzies: Tales of Comet Tails

Avast: a great daytime comet.

Photo by author; from the Greenwich Observatory collection.

Turns out, finding fuzzballs isn’t easy. If you’re like us, you’ve been spending many a morning hunting for two faint periodic comets: 45P/Honda-Markov-Padukov and 41P/Tuttle-Giacobini-Kresk. Yes, they’re both making close passes in 2017 as many a website have exclaimed, but they’re also both tiny and faint binocular objects from dark sky sites at the very best. Still, everyone from our repair guy to our landlord to random folks on social media have asked us how to see these intrinsically faint comets.

Obviously, even these minor celestial events pack a hefty modern social media punch in the general public’s eye. I go back and forth on this topic. On the one hand, I’m glad in this day and age of fake news ‘end of the world of the week’ killer space rocks that folks are still interested in real space news. There’s a true hunger out there. But us comet hunters know how faint these objects really are, and we fear the inevitable cries of that’s it? or worse yet I don’t see anything! and the eyepiece.

Follow comets like we do, and you realize that for every naked eye visitor, there are maybe ten binocular comets or so that come and go… and for every 10 binocular comets, another 10 don’t even make the +10th magnitude or brighter cut. That means that comets brighter than +6th magnitude are only 1-in-a-100, and we’d wager truly ‘great comets of the century’ are in the 1-in-a-thousand plus class.

Comets are fragile creatures. They often fail to live up to predictions, and under-perform or disintegrate (remember ISON back in 2013?) altogether. The least little bit of sky haze or light pollution with make them vanish from view, and all of that quoted brightness is smeared out over a large surface area like a nebula or cluster.

Flashback to 1996, and bright comets actually seemed common for a very few months, as Hyakutake and Hale-Bopp graced northern skies. In those halcyon days, an amateur astronomer’s job was easy, as I could simply take friends outdoors, look up, and say there it is, and wait for the ohs and ahs to follow. Both comets also gave us a good lesson in orbital geometry, as Hale-Bopp was a large bright comet nearly on the other side of Earth’s orbit, while Hyakutake was a smaller comet, close up. Now, if only Hale-Bopp had come by six months or so earlier…

But you can’t custom order celestial spectacles such as great comets from the Universe. Go back a bit further, and it seems like the skies were littered with bright comets in the 17th and 19th century… though we don’t really see banners adorned with Latin inscriptions trailing comets as depicted on medieval tapestries, and popes rarely excommunicate comets anymore.

And modern all-sky surveys such as PanSTARRS have upped the comet hunting game, making it much less likely that the next comet will have an umlaut in its name, to the consternation of science writers hunting for under the insert menu… when we find our first comet, we’ll insist it be spelled Comet Đckňsň…

There’s only one solution to this comet craziness: hubris. The Universe owes us a Great Comet. Period. Dot.

Post-script: There is currently a fine binocular comet in the dawn sky that’s receiving relatively little attention: Comet C/2017 E4 Lovejoy.

Speak Your Mind

*