Comet McNaught (2006/P1) - discussions - Page 3

CoombellKid · #41 06-01-2007, 01:09 PM

I tell ya I'm as keen as mustard, just wish we had some favourable weather,
thanx for post'n jjjnettie

regards,CD sunny days

Outbackmanyep · #42 06-01-2007, 02:41 PM

Hey Guys!
Been trying to spot it but cant as yet! Tried 2 nights ago but i'll try again tonight weather permitting!
I used my 7X50 Bins and couldnt find it......might take my camera just in case!
Been getting reports that its visible but has a 14 degree elongation which makes it hard to detect, also theres been a little trouble estimating magnitudes due to atmospheric extinction.
Keep you all informed !

Cheers!

CometGuy · #43 06-01-2007, 05:28 PM

Nice shots from norway, love the 1 second shot over the forest. There is also a really nice shot that I saw posted on cloudynights forums.

Outbackmanyyep,

Are you in the northern hemisphere at the moment? That is the only place it is currently visible from.

Houghy,

Its hard to give you exact settings, it depends on so many variables. For the deep twilight shots I would try to go to lowest ISO possible, set a fast aperture, then use AV mode. If you are using a tripod, work on 4 seconds maximum exposure at 100mm focal length. Last night I was testing with the 200 lens at f2.8 and it was metering about 1 second at ISO100 at about the equivalent location to the comet about January 17. I'd also attempt some longer, wider angle shots to show the tail pointing up from the western horizon.

I also attempted to image the comet at 2pm today with the 200 2.8 lens. With a stack of 8 x 1/1600 sec exposures Venus was very obvious, and the stellar limiting magnitude was 0.. I then tried 56 exposures at the comet's position and nothing was seen, but the comet would have had to have been at least as bright as mag -0.5 to be detected (you loose about 1.5 magnitudes in detection because the comet's light is more diffuse than a star).

Terry

dcnicholls · #44 07-01-2007, 10:14 AM

Those who aren't members of the Yahoo comets group may not have see John Bortle's comment likening a feature already apparent in Comet McNaught to one usually seen in Great Comets:

"I call particular attention to the Jager/Rhemann images of January 5th, where the enlarged pictures clearly showing a classic "shadow of the nucleus" down the center of Comet McNaught's inner tail. To my knowledge, this is the first comet to display this wonderful feature in some time (a classic feature in many past Great Comets). Over the next few days, I would anticipate that this apparent dark "void" will also
become a distinct visual feature of the comet when viewed with optical aid in the evening twilight."

A subsequent vusual report has already confirmed this feature. And a coma magnitude of 0.0 - going negative, possibly tracking to -3!

DN

Tamtarn · #45 07-01-2007, 10:21 AM

Thanks Glen for the map for those of us in Melbourne

dcnicholls · #46 07-01-2007, 10:22 AM

See also thread Comet Mc Naught http://www.iceinspace.com.au/forum/s...ad.php?t=16272

The comet may be 5 magnitudes brighter than predicted, and is showing some Great Comet features.

Mike, should we try to keep a single thread on Comet NcNaught? This could just be a biggie.

DN

davidpretorius · #47 07-01-2007, 10:47 AM

thanks glen, this is getting exciting

Orion · #48 07-01-2007, 11:04 AM

Wow that comet looks beautiful!

venus (Lydia) · #49 07-01-2007, 12:42 PM

Quote:

Originally Posted by h0ughy

To those attending Lostock, I will try to arrange for us to be able to access the mountain top to the east that over looks the area. That should give us an excellent horizon to take some happy snaps from the 17-20th January.

Terry given the evening sky and sunset, what camera settings would be generally recommended to start with?

Looks pretty much like my prediction of astronomers scurrying up a hill will come true

ballaratdragons (Ken) · #50 07-01-2007, 05:17 PM

If the clouds ever go away in time to see it at it's best

tornado33 · #51 07-01-2007, 06:52 PM

Excellent work. No wonder I couldn't image it I only took 3 shots to stack the other day. How did you stack yours, wouldn't the comet in each image be too faint to align?
Scott

h0ughy (David) · #52 07-01-2007, 08:29 PM

HAHAHAHA thats throws down the gauntlet to Scott Alder!!! Come on Scotty Serve NSW proud!!!!! GEt that AN going mate

CometGuy · #53 07-01-2007, 08:41 PM

Houghy,

LOL. I better not mention I'm originally from NSW

I reckon Scotty will bag it visually soon. Photographing its one thing, seeing it with your own eyes is another! Phil Creed - a noted observer in the states - just estimated mag -0.6 visual, its certainly getting bright.

Terry

jjjnettie (Jeanette) · #54 07-01-2007, 09:01 PM

LOL
Not naturalized yet Terry?

Orion · #55 07-01-2007, 09:27 PM

Quote:

Originally Posted by h0ughy

HAHAHAHA thats throws down the gauntlet to Scott Alder!!! Come on Scotty Serve NSW proud!!!!! GEt that AN going mate

Go Scotty, Go!

ballaratdragons (Ken) · #56 07-01-2007, 09:32 PM

I had no chance of finding it. Still cloudy from horizon to horizon

Astroman (Andrew Wall) · #57 07-01-2007, 10:01 PM

I only just got the email regarding your image Terry, was that REALLY taken during the day?? man that nucleus must be amazingly bright. Cant wait till it becomes more visible.

Congratulations ona very tough target.

glenc (Glen) · #58 08-01-2007, 11:13 AM

COMET C/2006 P1 (McNaught)
Total-magnitude and coma-diameter estimates (visual unless otherwise noted):
2007
Jan. 7.68, 0.5*, 2' (T. Scarmato, Calabria, Italy, 7x50 binoculars);
7.48, -0.5:*, -- (D. W. E. Green, Rowley, MA, 7x35 binoculars; alt. 4 deg, bright twilight; bright, small head with short tail);
7.30, 0.0:*, 1' (N. Biver, Meudon, France, 7x50 binoculars; 0.4-deg tail; alt. 5.7 deg; civil twilight);
6.96, -0.6:*, 0'.5 (P. Creed, New London, OH, 10x50 binoculars; alt 1.9 deg; civil twilight);
6.68, -0.3:*, 0'.3 (H. Dahle, Holmenkollen, Oslo, Norway, 7x50 binoculars; 0.8-deg tail in p.a. 0 deg.; alt. 1.5 deg.; naut. twilight);
6.28, 0.2:*, 1' (B. H. Granslo, Tryvann, Oslo, Norway, 7x50 binoculars; 1-deg tail in p.a. 0 deg, alt. 2.5 deg.; naut. twilight);
5.72, -0.5:*, -- (D. Moore, Dublin, Ireland, naked eye; 0.25-deg fan tail and 3' coma in 25x100 binoculars; alt. 2.5 deg);

http://cfa-www.harvard.edu/iau/icq/CometMags.html

tornado33 · #59 08-01-2007, 12:32 PM

Thanks Terry, excellent work there. Its overcast today, if clear tomorrow wonder how bright it will be.
Yes Im keen to see it visually, and will try each day its clear
Scott
PS wouldnt it be great if it got as bright as this one
http://en.wikipedia.org/wiki/C/1882_R1
It got to mag-17!
it could be seen next to the sun in the day without a telescope!

CometGuy · #60 08-01-2007, 01:24 PM

Yep Andrew, that was taken middle of the day.

A quick run home from work, and managed to get the comet again in daylight. Will take a bit of processing this time because high cloud was streaming across the Field of view.

Nobody has got it visually in daylight yet, but it wont be long.

Scott, its hard to predict how much effect forward scattering will be so its hard to predict. If there is minimal effect maybe mag -2 or -3.

1882 R1 passed just 0.006 AU from the sun and is possibly the brightest comet in recorded history.

Terry