New comet discovered in rendezvous field!

[Outbackmanyep]

A new comet has been discovered C/2009 U6 in a field which contained a rendezvous of 2 other known comets 29P and 81P.

Amateurs and Pro's had been photographing the rendezvous field but failed to see the third comet to the west of 29P.

A few had noticed it, including Mr Mattiazzo who imaged the rendezvous, but the faint background fuzzy was not given another thought!

So close yet so far! :confused2:
Link to the image here: Try and see if you can spot it!
http://astrosurf.com/obsdauban/images/cometes_img/29P-81P-09102718-9x120s-crop.jpg

[Blue Skies]

hmm. Is it the fuzzy streak to the right of the top comet, just beside the satellite trail? I suppose it would be easy to mistake it for a galaxy but its flaring a little too much to one side for that.

[mithrandir]

You mean this? That was my guess.

[mswhin63]

That was my guess too need a powerful scope to see that one as clear as the others.

[Blue Skies]

Yep, that's the thing.

[Outbackmanyep]

Yes thats the comet, a Jacquie said!

Please OBSERVE one more thing, notice the comet at the bottom of the image (81P) and see which direction the tail is pointing.....the new comet at the top to the right of 29P has a tail as well and it is pointing in the same anti-solar direction as the comet at the bottom........29P has no tail as we see it, activity on this comet seems to be minimal.

[mswhin63]

Possible that comet is much smaller, anyone measured it yet.

I noticed the other one to the left seems to be heading directly towards your location al-be-it slightly off centre. :scared:

[Outbackmanyep]

The newly discovered comet could be smaller but more likely further away from us i would imagine, i'd have to see the orbital elements.

[mswhin63]

I am no expert but was looking at the proportion of the comet compared to the larger one below looks the same or very close (ball x tail) as the tails only appear when it gets closer to the sun I assume the comet would be about the same.

Hey I might be totally out of league though. I am still learning.

[Outbackmanyep]

One thing i have learnt is that its like looking at asterisms, some things that are brighter seem closer but not necessarily so.....
Comet sizes can come down to a number of factors, size of the nucleus, gas/dust production, distance, intrinsic brightnesses......until an orbit is determined then anything about the comet can only be speculative.
Gotta start somewhere!

So if you went to the CBAT pages, find Comets, then dig up the orbital ephemerides you can compare their DELTA which is Earth-Comet distance.

http://www.cfa.harvard.edu/iau/Ephemerides/Comets/2009U6.html
http://www.cfa.harvard.edu/iau/Ephemerides/Comets/0081P.html

C/2009 U6
Date TT R. A. (2000) Decl. Delta r Elong Phs m1
2009 10 26 09 41.54 +13 09.2 1.788 1.711 69.3 32.9 16.6
2009 10 31 09 52.04 +12 54.9 1.767 1.736 71.8 32.9 16.6
2009 11 05 10 02.04 +12 42.6 1.745 1.761 74.4 32.9 16.7
81P/ Wild
2009 10 26 09 42.01 +12 39.3 2.092 1.969 69.0 28.1 13.0
2009 10 31 09 52.98 +11 47.6 2.020 1.943 71.2 28.9 12.9
2009 11 05 10 03.98 +10 54.0 1.949 1.917 73.4 29.7 12.7

Notice the difference in Delta (highlighted in red) in AU , so 81P is further away at the moment, but is much more active, so it's brightness will be higher. Elongation is the Comets angle from the Sun as seen from Earth.
r = Perihelion distance (closest approach to the sun) in A.U.
m1 is the predicted visual magnitude.
Don't worry too much about phase angle, thats better explained looking at an orbital simulation.

Hope this helps!