Machholz Does it again

[Paul D]

The name may not be new to some of you but for those who dont know it Don Machholz is famous for finding comets and on March 23 he found another one in Pegasus in his 18inch reflector. Its 11th mag with a 2' coma and no tail. This is his 9th comet but what makes this so interesting is this guy is finding these comets visually without the help of any CCD cameras at all.

[Rotorhead]

Don Maccholz is a real estate appraiser, like our member Brian T. Honestly, I don't know how someone with a full-time day job (and his own large company) can find the time to spend several hours a morning searching for comets. He has devoted over 600 observing hours to the hunt since his last comet. 600 hours sounds like a huge investment of time, but that is actually considered to be short by other visual comet hunters. One Japanese hunter averages over 1,000 hours per comet discovery.

Don's website indicates that this is his 11th comet. Maybe he has nine exclusive discoveries, because I know he has at least one co-discovery, and his website does not show the full names of all of his comets. And he says that his observing site is not completely dark, although it probably beats nearly anything we have around here. But with all the automated scopes involved in the NEO search, to find even ONE comet visually would be amazing.

[Greg Stone]

That is an amazing record. I wonder if there's anything that gives today's comet hunter an edge over earlier generations? He was using an 18-inch reflector, but at 77X he could not have had much more than a one degree field of view. That's alot more light-gathering power, though, than the 6-inch refractor used by Leslie Peltier. Peltier, considered a great amateur observer of his day, discovered just 11 comets in his entire, 80-year life. Perhaps the ability to quickly verify suspected objects - ie better charts - helps? BTW - Sky and Telescope puts this as the 11th comet Machholz as well, and gives these coordinates for March 26.8 UT at right ascension 23h 25.9m, declination +32° 13' (2000.0 coordinates). It's apparently already inside the Earth's orbit, or will be shortly.

[Bruce D]

It is an amazing feat to be sure, on several levels. Just the dedication alone would far surpass what most of us would be capable of. When I consider I often have a quite difficult time viewing these dim objects even when I know right where to look. He might have darker skies to give him a magnitude or two edge but through a scope that's not a big difference. Perhaps comet hunters in the past had it easier (individually) despite inferior optics, I think as there was a lot less competition 100 years ago. My guess is he has a favorite patch of the sky that he concentrates on, probably outside the prime area the professionals scour, and knows that area very well.

[Rotorhead]

When I worked on my Comet Hunter's pin for the Astro League, I noticed that many comets were very low in the morning sky when they were announced as being bright enough for visual observing, unless they were comets undergoing sudden brightening, like Holmes did a couple of years ago. I had to get up early to catch some of these comets, and thought that it was darned inconsiderate of these things to keep arriving at such weird hours. But there is a reason for it, and it is a simple one. The patch of sky that you are observing just before dawn contains a bunch of your old favorite constellations, right? Well, the reason you haven't seen them for a while is because they have been hidden behind the sun, and neither you nor any comet hunters - human or mechanical - have been searching within them. Comets entering these constellations on a trajectory that is behind the sun simply can't be seen until they rise out of the bright sunlight. So, as these constellations (and the comets hiding in them) slowly edge out from behind the sun, the western movement of the sky pulls them away from the sun by about one degree or 4 minutes of clock time each day. Thus, you have a narrow but pristine part of the sky that is all yours to hunt in and is slightly different each morning. Combined with the usual steadiness of the pre-dawn sky, about two hours before sunrise is the prime time to hunt comets. Any earlier, and those skies have already been looked at. Any later, and the sky is getting too bright. So, rather than having a favorite part of the sky that they are familiar with, the successful comet hunters slowly scan a narrow window (maybe the reason for a one degree FOV?) of 'new' sky each morning. The number of hyphenated comet names will attest to the near impossibility of a good comet hunter seeing a comet in that pristine wedge of sky and not have another eagle-eyed competitor see it an hour or two later just before the sun rises in his particular time zone. If two or more folks catch the same comet before it is verified by 'the authorities' at MPC (I believe) they all get to tag their name to it.

On some levels, this favors the human observer. The human eye is good at picking up faint objects, once a good eye is properly trained (probably the reason why some individuals are always finding comets, and other folks always aren't). The mechanical searches depend on enough movement to compare photos or data to detect that movement. A good human eye might be able to spot the tell-tale color and fuzziness of a comet and be certain of it almost immediately, even without movement. Since some of these dedicated comet hunters are using huge apertures and good locations, the playing field is somewhat leveled compared to the automated searchers, especially for comets in the 12 to 14 magnitude range. Bigger comets will be found even before they brighten, even before they come near the sun, by the automated searchers, while dimmer comets will be missed by the human eye even when they are overhead at midnight.

Still, it is simply amazing that this handful of observers are actually continuing to find comets despite the highly sophisticated mechanical competition.

Back in the day (about ten years ago - before the mechanized hunts began) I heard a talk by one local man who had discovered a comet by accident, while trying to put his new homebuilt dob on the Ring Nebula, and missed. The fuzzy that he saw in the ep refused to turn Ring-like despite several minutes of focusing, and he realized he was looking at a comet. How weird is that? Some of our club members may remember who that was, but I can't.

[Bruce D]

Thanks Bob you said what I meant, and much better than I ever could. A favorite window is a better way of explaining it than a favorite patch of sky. I have read about some comet hunters that like to concentrate their efforts a little higher off the eliptic than the 'prime real estate' on the theory that the bots aren't looking there as often.

[WCGucfa]

Hey I like all this comet talk. I've captured one of Machholz's comets in the past! I'm already after this new one!!

Bill G.

[Galactus]

The name may not be new to some of you but for those who dont know it Don Machholz is famous for finding comets and on March 23 he found another one in Pegasus in his 18inch reflector. Its 11th mag with a 2' coma and no tail. This is his 9th comet but what makes this so interesting is this guy is finding these comets visually without the help of any CCD cameras at all.

Can I use "the Word," Bob M? Greg? Can anyone say "Luddite" when describing Paul D? BTW, I agree with Paul: Kr, Macholz is pretty darned skilled. I am in awe...

[Rotorhead]

Bill, the previous Machholz that I remember was in late '04/early '05. It made a fine pass near the Pleiades in early January, and was a fine sight in binos. I think it was my first comet that I recorded after joining the club. Pete got a nice shot of it from Horseneck Beach.

viewtopic.php?f=19&t=193

I don't recall if you posted a shot of it, Bill.

[Pete]

Pete got a nice shot of it from Horseneck Beach. viewtopic.php?f=19&t=193

Actually that was Commander Cosmos' shot that I posted because he hadn't mastered posting at that time.

Pete