Hi all,
As per usual the Backyard Observatory Supernova Search (BOSS) team are happy to provide IIS members with breaking news.
Last night around 9pm, Greg Bock (of the BOSS collaboration) discovered a possible very bright supernova in a far southern galaxy IC4901 in Pavo.
By the time Greg was able to blink the image against his reference image the galaxy had dipped below his horizon. He rang me at 11pm to see if I could get a confirming image. I had just closed the observatory due to complete cloud cover, but thought what the heck, I will move the 'scope to the galaxy (now way over in the southwest at 28 degress altitude)and just start imaging in the hope of a break. Well that's what happened, a small break allowing enough time to get a confirmation image. While Greg and Colin Drescher worked the numbers (position magnitude, offset etc) the sky cleared enough for me to get a better image at only 20 degrees altitude. The object was reported as a possible supernova (PSN) on the CBAT TOCP Page / Bright supernova page, you will see it listed as unknown discoverer at this stage until all the formalities are done http://www.rochesterastronomy.org/supernova.html
Designated PSN19542141 -5842390 the position (J2000) is 19 54 21.42 / -58 42 39 and its magnitude 14.5r which means it should be visual for 12inch scope owners (Hi Ron Knight!).
Now its only a PSN until the professionals get a spectra and here's where all our hard work is paying off. We have a collaboration with a professional astronomer studying supernova and she is going to try to get a spectra using one of the 6.5m Magellan 'scopes at Las Campanas Observatory in Chile in the next several hours. Once this is done she will send it to the IAU and it should then have an official designation and be released on a Central Bureau Electronic Telegram (CBET). We also have professional collaboration with the SALT telescope astronomers in South Africa and no doubt being bright will be of interest to them.
So there's the report, but what about the guy who discovered it, Greg Bock. As many know Greg and I work alternate Saturdays at Sirius Optics, more for the love of it than an extra income to pay for astro toys. Greg has been a very keen supernova hunter for many years and clearly my successes and indeed much of BOSS would never have happened without the groundwork, hard slog and assistance he laid down over many, many years. We both had great excitement in confirming some of Bob Evans visual discoveries years ago. Greg is also, like Stu Parker an absolute perfectionist superb astro imager.
You may not be aware Greg has one of his images used to pan across the sky in the Carl Sagan Cosmos DVD set as well as having a huge blown up image of Crux on display in the Carnegie Institute (I think its that one) and lots of other images on book covers etc. Now Greg has never given up on finding his own supernova, literally tens of thousands of images - not of nothing, but meticulously building up a library of reference images that last night delivered huge rewards.
I thank and congratulate him on his persistence and help. Goes to show what keen amateurs can achieve.
I will keep you posted on the outcome of the spectra and look forward to someone spotting it visually. Greg will no doubt respond and place an image here later today, well I don't want to steal all his thunder.
PeterM.
Last edited by PeterM; 20-10-2011 at 02:32 PM.
Reason: typo
This is one of the best parts of Astronomy is to see a friend achieve something he has wanted for so many years.
Greg has been key part in so many of mine and Pete’s and Brendan’s Supernova discoveries since the group was formed a few years back and way before that has done alot of work with Bob Evens confirming his Supernovae. But he always wanted to get that one of his own....got it now after so many years of trying and seeing others getting them. What about that for staying power!!!
I woke up to all the excitement at 4am as all this happened while I was asleep (dam 3 hour difference).I got yelled at from My wife Lynn who was by this time in the Kitchen getting ready to go to work as I was still in Bed(as usual) "GREGS GOT ONE "as she read the SMS and emails on the phone.
So all of New Zealand breaths a sigh of relief.
Well done mate a great find. A great bright SNe in a really nice galaxy. Great for you and for BOSS
Looking forward to seeing some of those images you will be taking over the next few weeks
The only thing I am really annoyed about is that I won’t be able to share a port or two with you over this. But I will have a couple for you over here. I hope the wait was worth it
Very happy for you ......enjoy
Stu BOSS-Backyard Observatory Supernova Search
Hi Guys,
well, fingers crossed that this does turn out to be a new supernova! Only a good spectrum can prove it, so hopefully, that won't be too far away.
Thanks for the generous thoughts above, and your ongoing and stoic support. It's great to work in such a supportive and helpful team like this, particularly when we can provide some value back to the professional work.
I have been imaging galaxies for more than 10 years and taken more than 50,000 images to finally discover one for myself, rather than find a pre-discovered one, or an asteroid, so i hope it's also not the last for another 10 years!!
I have attached a jpg copy of IC4901 and the suspect, and would like to hear if anyone can see it visually too. At mag 14.5, it should be in the range of moderate scopes (say 12" at least) under dark skies.
Thanks Mike, yes, as usual it was a great team effort.
After I realised the object was new, I checked for asteroids, variable stars, and previous discoveries in that galaxy, and then notified Peter who managed to get a second image between thick clouds to confirm that it was a real object and had not moved. Meanwhile Colin and I did the astrometric analysis for position and magnitude, then Col posted the TOCP, and I prepared the verbose report for the CBAT.
The only things that didn't play ball were the clouds, and my laptop that blue-screened just before I sent the CBAT report!! That cost me another hour between 12:30am and 1:30 am preparing another report for CBAT!
The really unusual aspect of this discovery is that Stu slept through the whole thing!. I guess being 3 hours ahead of us can get in the way a bit. He missed out on the fun and excitement for a change....
Congratulations Greg,and the team
At last one for yourself after all these years,the first of many I hope I will attempt a visual report as soon as the clouds go away.
Cheers
Congrats, Greg, on the candidate supernova discovery.
It can be really hard to find good-resolution reference images of far southern IC catalog galaxies.....indeed, I would go so far as to call them the least studied Bright Galaxies in the sky (some of the bright non-NGC/IC galaxies with ESO designations..... are also virtually unknown)
I have two images of IC 4901 on file, and here they are.
(IC 4901 was also imaged in the H-alpha bandpass, in the survey known as SINGG)
(The NED database (//ned.ipac.caltech.edu) also contains various images of IC 4901.)
Thanks Robert and Paddy,
yes, thanks for those images, I have had trouble locating good images of it, so I guess I'll have to take some for myself.
The other good news is that a spectrum taken at Las Campanas at La Serena in Chile today now confirms it to be a young blue type II supernova, so early light brightness measurements are welcome too.
I continue to "recoil in fear and awe" at the sight of the new supernova you discovered!
Here is a (continuum subtracted) H-alpha image of IC 4901 which was made by the southern Ha imaging survey called SINGG. The image is at a logarithmic scaling, and there is also a Broadband Red Light channel which is added to it, displaying here as blue.
H-alpha images of southern galaxies made in the SINGG survey can be found at:
Now that we know this to be a very young Type II event (core collapse of a giant star) it is very likely to brighten, making it visible possibly in say 10inch scopes, maybe less. The galaxy is approx 101 Light years away and a very fine target for astroimagers. Robert (Madbadgalaxyman) maybe able to give us some indication of how bright this event could become.
There are very few Supernova each year that do become visual objects so here is a challenge to the eyeball amateurs out there.
Use the image in the above posts and spot the "supernew star" then ponder what happened to it 100 million years ago. The incredible power that was unleashed. As the light enters your eye think of what was happening here on Earth when that light left the doomed star and how far we have come. Think of what has happened to that star over the last 100 million years and how from its destruction, the new elements created in the inferno may now be in the throes of forming a new, very different star. A process that at least in our case led to an amateur astronomer on a planet circling a distant much smaller star, roll back the roof of his observatory one starry evening, point his telescope at a distant galaxy and be the first out of 6 billion to view an event that happened 100 million years ago.
I just love it.
PeterM.
Thanks, Pete, for the interesting comments. It is interesting to hear, again, from an old colleague.
If my previous experience with the many brightish IC galaxies in Pavo is anything to go by, data on this galaxy will be hard to come by.
I will have a look at how bright this SN might become (after I have got over yesterday's "data overload" from considering two dozen papers and a hundred images about M31 !!)
From the available redshift, this galaxy is going to be at least 50 percent further away than the Virgo Cluster of galaxies, so the SN at maximum probably won't burn out the observer's eyeball.
IC 4901 seems to be in a remarkably low density region of space, at least judging from the fact that few galaxies in Pavo share its redshift (and distance). Most of the bright galaxies in Pavo are in the supercluster at about twice the distance of IC 4901.
But the "Pavo" effect of scant available data means that there are actually a lot of galaxies in this constellation for which even simple redshift data is not available!
Last edited by madbadgalaxyman; 21-10-2011 at 10:52 AM.
Reason: more info
Hi "Recoiling Robert", and everyone else above....
Robert, thanks for the Ha image above, and the link to the SINGG survey.
It will be interesting, if I can do it, to overlay the Ha image with my discovery image to see if there is a nice correlation between a particular Ha region and the supernova.
I received confirming advice early today from Las Campanas Observatory about the spectrum. Our friends there were very quick to willingly help out as much as they could by interrupting their planned schedule and recording the spectrum. They used the 6.5m Magellan II Clay telescope to identify the SN as a young type II P, where the 'P' stands for a 'Plateau' type. This means that the light curve will decrease more slowly over time than other type II L's, and type 1's,so it will be interesting to image it and develop the light curve over the next few months.
The spectrum was also recorded earlier today by the NTT team at La Silla, and agrees with the type IIP result, fantastic.
We have some clear weather coming soon I hope, if so, I will also try to obtain some hi-res images of the SN too.
Last edited by Greg Bock; 21-10-2011 at 12:11 PM.
Reason: add text
