British Astronomical Association
Supporting amateur astronomers since 1890

Secondary menu

Main menu

Home Forums Comets
Terms of use

new visual comet discovery by Don Machholz

24 posts / 0 new
Last post
Denis Buczynski's picture
Offline
Last seen: 4 days 17 hours ago
Joined: 05/03/2014 - 13:04
new visual comet discovery by Don Machholz

This object is now designated as DM001 on the Posssible Comet Confimation Page of the Minor Planet Center

Róbert Fidrich Photometry of performed by Daniel Bamberger on my 60-60s CCD images made using T20 refractor with green filters at itelescope.net Mayhill, NM show 10.2 magnitude total brighness.
https://www.dropbox.com/s/flb6mbw4r33eer9/machholz.gif?dl=0

Offline
Last seen: 2 days 9 hours ago
Joined: 26/04/2018 - 11:12
This looks worth following up

This looks worth following up :-) I tried to get the ephemerides from JPL/MPC but inputting DM001 is not recognised.  Any guidance on what/where to search for would be welcomed. 

Thanks

Helen

Denis Buczynski's picture
Offline
Last seen: 4 days 17 hours ago
Joined: 05/03/2014 - 13:04
DM001

Hi Helen, here is a preliminary ephemeris by Nakano published on CBET 4569

Nakano provides the following preliminary ephemeris for the comet:

2018 TT R.A. (2000) Decl. Delta r
Nov. 5 12 06.22 -02 26.5 1.549 1.013
6 12 10.91 -02 21.2 1.549 1.012
7 12 15.60 -02 15.7 1.550 1.011
8 12 20.29 -02 10.2 1.550 1.011
9 12 24.97 -02 04.6 1.551 1.012
10 12 29.64 -01 59.0 1.552 1.012
11 12 34.30 -01 53.3 1.553 1.013
12 12 38.95 -01 47.6 1.555 1.014
13 12 43.59 -01 41.8 1.556 1.015
14 12 48.22 -01 36.0 1.558 1.017
15 12 52.84 -01 30.2 1.560 1.019

Offline
Last seen: 2 days 9 hours ago
Joined: 26/04/2018 - 11:12
Thanks Denis :-)  for both

Thanks Denis :-)  for both the data and the reference

I have time on the Faulkes Telescope and so was hoping to gather some useful data on this comet - no chance of doing it from home!

Helen

nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
I gave a talk to Newbury

I gave a talk to Newbury Astro Soc last Friday when I said that it was now very unlikely that we would get visual comet discoveries. How wrong I was! Congratulations to Don and the other independent discoverers of this comet.

An ephemeris based on all the available astrometry up to this morning is here. It was produced using Bill Gray's FindOrb. These elements are still very uncertain but it looks like it is heading to a perihelion in early December. It is currently moving south and the elongation is decreasing so it will become increasingly difficult to observe. From the UK it is currently a morning object amongst the galaxies in Virgo. The column headed "/sig gives some idea of the position uncertainty (in arcsec).

Any observations (astrometry, photometry or images) would be gratefully received. 

nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
Denis and I managed to image

Denis and I managed to image this comet this morning from Scotland. I've just posted a very quick process of one of the images here.

djswan2002's picture
Offline
Last seen: 25 min 17 sec ago
Joined: 20/04/2017 - 19:58
Superb

Very nice. Hopefully I’ll be granted a half hour patch of clear skies in the morning some day soon. D

Offline
Last seen: 19 hours 9 sec ago
Joined: 05/03/2014 - 07:38
visual observation

I believe Peter Carson and Andrew Robertson saw this visually with an 18" telescope from Suffolk this morning.proving that East Anglia does have the best weather :-) I am sure they will comment further.

Owen

nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
Owen. Yes, Andrew Robertson

Owen. Yes, Andrew Robertson and Peter Carson had a good view through Andrew's 18-inch telescope at Haw Wood. They commented that the comet was bright and easy. 

The latest ephemeris is here using all astrometry I have so far. I've done this starting 60 days before now and the positional uncertainties are now quite small. The comet has been at a small elongation for all of this time and was discovered when it was at its largest elongation. This is now decreasing. The comet has a small q (0.39 au) and is brightening rapidly.

Please try to observe this comet at any opportunity.

Nick. 

Grant Privett's picture
Offline
Last seen: 12 hours 4 min ago
Joined: 28/12/2014 - 18:30
Magnitude

What sort of brightness are we thinking?

Tuesday morning is looking clear here....

nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
Probably 7.5 - 8.0 this

Probably 7.5 - 8.0 this morning. Any predictions will be very unreliable since it could be in the final stages of a bright outburst or not. Getting up early to observe it is the only way to find out!

Offline
Last seen: 14 hours 4 min ago
Joined: 10/03/2014 - 09:25
Sketch

My sketch from this morning attached. Location Haw Wood, Suffolk, 18" F4.5 Dobsonian, 13mm Ethos e/p, x160.Thanks to Owen for alerting me (I had no e-mail) and Nick for the latest accurate co-ordinates.

Andrew

nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
C/2018 V1

Official designation is C/2018 V1.

djswan2002's picture
Offline
Last seen: 25 min 17 sec ago
Joined: 20/04/2017 - 19:58
Update

Clear skies this morning - 12/11/2018 05:08. Still quite bright, with ion tail visible.

Attachments: 
djswan2002's picture
Offline
Last seen: 25 min 17 sec ago
Joined: 20/04/2017 - 19:58
Crazy satellite too!

Found this (!) frame in the set.

Attachments: 
Xilman's picture
Offline
Last seen: 21 hours 18 min ago
Joined: 24/03/2018 - 15:17
Beautiful!

Beautiful!

djswan2002's picture
Offline
Last seen: 25 min 17 sec ago
Joined: 20/04/2017 - 19:58
Slightly clearer image

DDP tends to bloat the stars and make them furry. Here's a clearer image with the ion tail quite distinct. 12 x 10s, midpoint 05:14:30.

Attachments: 
djswan2002's picture
Offline
Last seen: 25 min 17 sec ago
Joined: 20/04/2017 - 19:58
Position

As Nick has said, the orbit is obviously very well determined. I updated MPCORB in Astrometrica, and the comet was spot on the predicted position.

Attachments: 
nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
David - Great image showing

David - Great image showing the tail. Denis and I managed to get some astrometry on it this morning but the conditions were poor so our images are rubbish. 

nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
Here's a quick process of a

Here's a quick process of a widefield image I took this morning with Denis Buczynski in northern Scotland. I'll do a better job of processing this later and put the result on my members page. The galaxy is NGC4753.

djswan2002's picture
Offline
Last seen: 25 min 17 sec ago
Joined: 20/04/2017 - 19:58
Tail

Am I imagining things, or are there two tails in this image?

nickjames's picture
Offline
Last seen: 1 hour 3 min ago
Joined: 12/10/2013 - 18:16
Yes there is. You can see it

Yes there is. You can see it better in the stack attached. This is stacked on stars so the comet is trailed and the background is not yet sorted but it shows the ion tail going out of the field.

Attachments: 
Peter Carson's picture
Offline
Last seen: 22 hours 8 min ago
Joined: 06/04/2014 - 20:41
Long thin tail this morning

This morning (2018 Nov 13th) the C/2018V1 is showing a nice long thin tail. My image is showing a tail over 23 arc minutes long extending out the field of view of my camera.

Offline
Last seen: 18 hours 57 min ago
Joined: 15/03/2014 - 23:44
Also caught C/2018 V1 this

Also caught C/2018 V1 this morning with C8 Hyperstar and ASI183MM 20x20sec exp. Tail shows up on this reversed image.

David