While observing NGC 1399 (fornax cluster) last night, I noticed a star at the galaxy's Northeast edge, which doesn't seem to be there on any images I've searched for so far. One image I found shows a star at a similar location to where I saw it , but it appears to be extrememly faint, beyond the capabilities of my scope compared to other field stars that appeared very faint to me.
Actually no, that is not it, NGC 1396 is to the west. This star was to the north or notheast of NGC 1399's core and was actually "in" the galaxy's outer extremeties.
I actually attempted to find NGC 1396 and couldn't see it - too faint. This was a point source which I saw.
Exciting stuff isn't it. I have pmed you with my home number so please call me when you can so I can get a bit more info and a contact. Plan is to image the galaxy this evening, have also sent onto Stu Parker.
Fingers crosssed for you, would be great to have a visual SN discovery under your belt. Lets see how we go.
Was good to talk with you Sab, I got a real sense of your excitement and enthusiasm for astronomical discovery, that is very encouraging to us "older" blokes. I will have great pleasure in taking an image of this for you and cross my fingers.
As a matter of interest I have attached a scan of NGC1399 from the Thompson & Bryan Supernova Search Charts. You will note there is a star on the NE edge of the galaxy and by the magnitudes listed at bottom it would be about mag 13.5-14 but is this the one that Sab is seeing? maybe, but we should never just assume, there have been missed discoveries because an observation was not questioned or followed up.
As Sab has gone to the trouble of presenting us with the challenge I think it would be a good exercise for the visual observers who are suitably equipped to also have a squizz at NGC1399 and we can then all present our reports and images (and perhaps a visual discovery to Sab) in this thread.
Not meaning to speak on Sabs behalf but he is in a rather light polluted area and said that he couldn't get NGC 1396 as it was too dim. So the object that Sab saw mush have been a fair bit brighter.
"I actually attempted to find NGC 1396 and couldn't see it - too faint. This was a point source which I saw".
Was good to talk with you Sab, I got a real sense of your excitement and enthusiasm for astronomical discovery, that is very encouraging to us "older" blokes. I will have great pleasure in taking an image of this for you and cross my fingers.
As a matter of interest I have attached a scan of NGC1399 from the Thompson & Bryan Supernova Search Charts. You will note there is a star on the NE edge of the galaxy and by the magnitudes listed at bottom it would be about mag 13.5-14 but is this the one that Sab is seeing? maybe, but we should never just assume, there have been missed discoveries because an observation was not questioned or followed up.
As Sab has gone to the trouble of presenting us with the challenge I think it would be a good exercise for the visual observers who are suitably equipped to also have a squizz at NGC1399 and we can then all present our reports and images (and perhaps a visual discovery to Sab) in this thread.
Quote:
Originally Posted by DavidU
Not meaning to speak on Sabs behalf but he is in a rather light polluted area and said that he couldn't get NGC 1396 as it was too dim. So the object that Sab saw mush have been a fair bit brighter.
"I actually attempted to find NGC 1396 and couldn't see it - too faint. This was a point source which I saw".
No probsa David... NGC 1396 was invisible to me, I'd estimate this "star" as around Mag 14.
PeterM.
G'day Peter,
mag 13.5-14 is well within my reach, it could well be the star I saw. On one image I looked up it showed a star very close to the galaxy's nucleus in the position I described, but it looked much fainter than a couple of 15th mag stars (a 3rd was 12th mag) I saw rougly halfway to NGC 1387 - and also much closer to the nucleus which IMO would've been impossible to split given my aperture and sky conditions. And 15th mag is very close to the limit from my location and aperture.
First off, very well done PGC in having a sharp-eye and noticing something that looks as though it might be out of place at least. Whether or not it is a supernova candidate an image will obviously tell us a lot more.
I see (as others have noted) there is a faint star 2 arc-mins in PA 29.5 from centre (my measure using the plate) on Realsky with Megastar. This is USNOA2 0525-1251531 but there is no assigned magnitude which is not uncommon as accurate photometry can be problematic with the star being superimposed on the outer reaches of the galaxy. At a guess I'd say it was about the mag 15.0 mark based on appearance on the plate. This seems at first blush to be the one plotted on the chart.
Given the distance modulus for NGC 1399 (see the supernova search chart attachment) the expected brightness of a supernova of type I is 12.7. Type II events are generally about 1.5 to 2 mags fainter than T1 so lets say 14.5-15 -- so it could fit a TII event or alternately it could be a T I that is a peculiar event or it might have been caught before maximum brilliance, or could be obscured.
On the other hand, most likely it is USNOA2 0525-1251531 -- my gut feeling is that it is this star but fingers crossed for you -- you never know! Best of all you were not merely taking a casual glance but observing -- and as I said well done for that at least!
I'll take a look tonight myself -- if it clears up !!
First off, very well done PGC in having a sharp-eye and noticing something that looks as though it might be out of place at least. Whether or not it is a supernova candidate an image will obviously tell us a lot more.
I see (as others have noted) there is a faint star 2 arc-mins in PA 29.5 from centre (my measure using the plate) on Realsky with Megastar. This is USNOA2 0525-1251531 but there is no assigned magnitude which is not uncommon as accurate photometry can be problematic with the star being superimposed on the outer reaches of the galaxy. At a guess I'd say it was about the mag 15.0 mark based on appearance on the plate. This seems at first blush to be the one plotted on the chart.
PA 29.5 I assume would be more NW of the galaxy, and I'm certain this object was brighter than 15.0, considering the galaxy was moving into the light pollution to the west, and it generally appeared to be viewed with similar ease to a 13th or 14th mag star. It also appeared to be at around PA 340-350, assuming north is PA 360 or 0.
Quote:
Given the distance modulus for NGC 1399 (see the supernova search chart attachment) the expected brightness of a supernova of type I is 12.7. Type II events are generally about 1.5 to 2 mags fainter than T1 so lets say 14.5-15 -- so it could fit a TII event or alternately it could be a T I that is a peculiar event or it might have been caught before maximum brilliance, or could be obscured.
On the other hand, most likely it is USNOA2 0525-1251531 -- my gut feeling is that it is this star but fingers crossed for you -- you never know! Best of all you were not merely taking a casual glance but observing -- and as I said well done for that at least!
I'll take a look tonight myself -- if it clears up !!
Best,
Les D
I'd be super excited if it was a super nova...I contacted PeterM and he says he'll image the galaxy tonight.
PA 29.5 I assume would be more NW of the galaxy, and I'm certain this object was brighter than 15.0, considering the galaxy was moving into the light pollution to the west, and it generally appeared to be viewed with similar ease to a 13th or 14th mag star. It also appeared to be at around PA 340-350, assuming north is PA 360 or 0.
I'd be super excited if it was a super nova...I contacted PeterM and he says he'll image the galaxy tonight.
No, PA is measured in degrees East of North, so PA 30 (not splitting hairs) is northeast. Remember that with many astronomical images (like the DSS at STScI in particular) north is at the top and west to the right.
Here's hoping -- we'll probably know in a couple of hours.
