Observing comets

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michael feist
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Observing comets

Post by michael feist »

Where have all the binocular comets gone!? This is a rhetorical question, and do not expect an answer, and I am just bemoaning the fact.
Reasonably bright comets, i.e. those that could be seen using binoculars, monoculars or small telescopes, at say magnitude +7 or brighter, were a staple diet for my observing focus. Apart from Neowise last year, there have been none. Not so long ago one could sometimes see two or perhaps even three each year.
Addendum : To add to this I looked up my records if comer observations, and, in fact some years there were more than three comets observed.
Three comets were seen during 2000: McNaught-Hartley C/1999T1: Linear C/2001A2: Linear C/2000WM1
Five comets were seen during 2002: Utsunomiya C/2002F1 : Ikeya 153P : Swan C/2002O6: Hoenig C/2002O4 : Kudo-Fujikawa C/2002X5.These are just a few examples, but in the year 2000 a single comet only was seen, Linear C/1999 S4: and only one in 2011, Garradd C/2009P1, also only one in 2019 Iwamoto C/2018Y1 and only one in 2020 as Neowise C/2020F3.
Every other year has produced two, three, four or five reasonably bright, binocular or small scope comets.
So it is not just my imagination. They do seen very thin on the ground, or should I say, in the sky.
Regards mike
SkyBrowser
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Re: Observing comets

Post by SkyBrowser »

We can always keep our fingers crossed for C2021 A1. Earlier in the year it was being touted as a naked-eye job at Christmas. But, as ever, estimates have been down-graded. However, they're still suggesting mag 8 or so in mid-December. It'll be racing past Arcturus at that time.

On the 3rd of December it'll be extremely close to M3. It might even go over the top of it!
mikemarotta
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Re: Observing comets

Post by mikemarotta »

It is an interesting question. Astronomers--especially citizen scientists-- have been observing and reporting comets for 200 years. We should have some statistical insight about their frequency.
In June 2021, we’ll be visited by a short-period comet 7P/Pons–Winnecke which has an orbital period of about 6 years. This comet has been known for more than 200 years since its discovery in 1819 by a French astronomer Jean Louis Pons. 7P/Pons–Winnecke will get quite close to the Earth (about 0.44 AU) in June, but it won’t be sufficient to make it a bright object in our skies. It will reach a visual magnitude of about 10 and will be best visible through telescopes from the Southern Hemisphere.

Another short-period comet, 15P/Finlay, will fly by our planet in July 2021, brightening up to magnitude 10. This comet was discovered in 1886 by a South African astronomer William Henry Finlay. An interesting fact: of all the short-period comets, 15P/Finlay has one of the smallest minimum orbit intersection distances (MOID) with the orbit of the Earth. In 2060, it will pass roughly 0.04 AU from us, which is only about 6.0 million km. This will be one of the closest comet approaches to our planet in history! Alas, we’ll have to wait a bit (to put it mildly).

https://starwalk.space/en/news/the-brig ... 0-and-2021
I found some other sites, one from Bortle Himself, but they are not secure socket https. So, they have not been edited actively for a decade or more. ALPO does have an active Comet Section. They get excited about 19th magnitude sightings, a bit harder to spot with my own instruments.
Michael E. Marotta
Explore Scientific 102 mm Refractor
National Geographic 70 mm Refractor
Ploessl oculars 40mm to 6mm 2X Barlow
mike49mercury@gmail.com
michael feist
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Re: Observing comets

Post by michael feist »

The BAA Comet section lists a number of currently visible comets. One is magnitude 9.5 but at a poor elongation, the rest are magnitude 11 to 14. Visually I would only go looking for a comet that was perhaps +7 or perhaps 7.5 or brighter. Most comet observers seem to use imaging these days and can pick up much fainter comets and lots of colour and detail. I only view visually, belonging to the pre-computer age. Regards maf
mikemarotta
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Re: Observing comets

Post by mikemarotta »

Thanks for the suggesition, Michael. I am also a BAA member. I just don't visit there often (or often enough,it seems).

Best Regards,
Mike M.
======================
Member
AAS BAA SAS SPA ASP
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=======================
Michael E. Marotta
Explore Scientific 102 mm Refractor
National Geographic 70 mm Refractor
Ploessl oculars 40mm to 6mm 2X Barlow
mike49mercury@gmail.com
mikemarotta
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Re: Observing comets

Post by mikemarotta »

Just arrived in the mail. First edition.

One of my hobby interests is celestial mechanics. I am a member of the AAS Dynamical Division. But I don't do much, or have not. I had a couple of directed study classes in college and I have several textbooks, but the problems are all arbitrary. A planet has a period T what is the longitude of the ascending node, or whatever. Even if the answer is in the back of the book, there's not much you can do with that. There's no way to check your arithmetic against a real object over time. This will help.
Marsden Comets 1st ed (s) copy.jpeg
Marsden Comets 1st ed (s) copy.jpeg (113.43 KiB) Viewed 86 times
Michael E. Marotta
Explore Scientific 102 mm Refractor
National Geographic 70 mm Refractor
Ploessl oculars 40mm to 6mm 2X Barlow
mike49mercury@gmail.com
Mogget
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Re: Observing comets

Post by Mogget »

I had a copy of the 1986 edition of that catalogue a long time ago. I am currently using Halley - Electronic Ephemeris of Comets (Yuri Bondarenko) to study the long term orbital evolution of numbered short period comets.
brian livesey
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Re: Observing comets

Post by brian livesey »

On the subject of comets, I very recently acquired a charity shop book titled “The Comet-Sweeper” by Claire Brock. The book is a biography of Caroline Herschel and looks like a good read.
brian
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