Hi All,
this must be a record. Stuart Parker discovered supernova number 38 for BOSS early this morning in ESO 462-16 (aka PGC64605). Its his fourth discovery since 26 June.
He has certainly kept me busy with analysing his images.
The interesting thing this time though is that we notified our contacts in Chile for a spectral analysis, which triggered observing runs at both Las Campanas, which confirmed it in near infra red images, and also the 8.2m Gemini South telescope at CTIO which confirmed within 12 hours of Stu's find that it was an early type 1a, about 1 week before maximum light.
It is currently about magnitude 16.3 and brightening, so it wont be a visual target for many smaller amateur scopes unless they are fitted with a camera.
I'm flat out just keeping up with the email traffic that each discovery and its analysis generates. I checked on today's effort, which runs to 45 emails in 12 hours. That is, received and sent between Stu, me, Pete, Col, and a few of our contacts in Sth and Nth America.
Also yes David, I seem to remember when Stu called me while I was driving to work this morning with yet another discovery, it was a bit more colourful than 'strewth'!
Stu is having a fantastic run indeed, but it is from sheer hard work and dedication. He has taken some 3000 images in the last few days. Greg, Colin and I are now using Drop Box to access images so that we can assist in blinking Stu's images. This gives us something to do while the weather in Brissy remains wet. New Zealand the land of the long white cloud? I don't think so!
The other thing to note here is just how much support professional astronomers are giving the discoveries. If you could see the list of Astronomers that we now have daily email contact with from 'scopes like the Gemini, Magellan, SALT etc it is just unbelievable.
The science that has come from some of the BOSS discoveries is also astonishing and shortly we will be able to let you know about a paper recently submitted to the Astrophysical Journal (with our names attached to a long list of professional astronomers!!! Wow) that has significant implications for Supernova types, maybe even rewriting the textbooks!
It just gets better and better.
we have been advised from Chile that it is likely this object is a "super-Chandra" SN Ia, reminiscent of SN 2006gz, 2007if, 2009dc.
I researched "Super-Chandra", and have extracted some info below.
If it is a Super Chandra, it looks to me like Stu has stumbled upon a very rare object indeed, which is still quite a mystery.
A type 1a supernova is normally a white dwarf star less than 1.4 solar masses, and is part of a binary system. In this case however, was it an explosion of a single white dwarf of mass greater than the Chandra limit of 1.4 solar masses in a binary system, or a merger of 2 white dwarves, or something else?
I would imagine that this discovery should generate a lot of interest and intense observing time to try to add to the missing body of knowledge here?
At this stage, it is still early days, so things could change, but we'll keep you posted!
From wikepedia:
In April 2003, the Supernova Legacy Survey observed a type Ia supernova, designated SNLS-03D3bb, in a galaxy approximately 4 billion light years away. According to a group of astronomers at the University of Toronto and elsewhere, the observations of this supernova are best explained by assuming that it arose from a white dwarf which grew to twice the mass of the Sun before exploding. They believe that the star, dubbed the "Champagne Supernova" by University of Oklahoma astronomer David R. Branch, may have been spinning so fast that centrifugal force allowed it to exceed the limit. Alternatively, the supernova may have resulted from the merger of two white dwarfs, so that the limit was only violated momentarily.
From Yale News, March 15 2010:
Since 2003, four supernovae have been discovered that were so bright, cosmologists wondered whether their white dwarfs had surpassed the Chandrasekhar limit. These supernovae have been dubbed the “super-Chandrasekhar” supernovae.
Now Richard Scalzo of Yale, as part of a collaboration of American and French physicists called the Nearby Supernova Factory, has measured the mass of the white dwarf star that resulted in one of these rare supernovae, called SN 2007if, and confirmed that it exceeded the Chandrasekhar limit. They also discovered that the unusually bright supernova had not only a central mass, but a shell of material that was ejected during the explosion as well as a surrounding envelope of pre-existing material. The team hopes this discovery will provide a structural model with which to understand the other supermassive supernovae.
Using observations from telescopes in Chile, Hawaii and California, the team was able to measure the mass of the central star, the shell and the envelope individually, providing the first conclusive evidence that the star system itself did indeed surpass the Chandrasekhar limit. They found that the star itself appears to have had a mass of 2.1 times the mass of the Sun (plus or minus 10 percent), putting it well above the limit.
Being able to measure masses for all parts of the star system tells the physicists about how the system may have evolved—a process that is currently poorly understood. “We don’t really know much about the stars that lead to these supernovae,” Scalzo said. “We want to know more about what kind of stars they were, and how they formed and evolved over time.
Hi all,
Yes, Allan, we certainly are proud of it.
To add further to a question that DT asked last week about Stu's success at finding these, he has been particularly productive at imaging galaxies from New Zealand over the last 2 weeks or so because he has both observatories imaging, and has much clearer weather than we do here in Queensland. As I write this, we have had 3 days of cloud, with much of Queensland recording more rain for July than has been recorded in the last 60 years! And, we still have several days of cloud with rain increasing up to the weekend, so no more imaging for Peter and I here.
To give you an idea of image numbers, in the last 10 days since 1 July, I have imaged and checked about 400 of my own images taken at my Windaroo Lakes Observatory, and checked over 200 of Stu's images, so 600 total. Now, 400 images checked is a healthy number for me to image and check after only 10 days. Peter has probably checked the same numbers as me.
However by contrast, Stu has taken more than 3000 images altogether over the same time!!
Wow! Absolutely fantastic work by Stu and the team!
Greg, thanks for the background on the "super-Chandra". If this latest
supernova happens to fall into this class, based on the information you provided,
it certainly will be of intense interest to the professionals.
Could you please keep us posted on this thread if it turns out to be true?
Might fall into that exclusive class of incredibly rare finds by an amateur observer.
The science that has come from some of the BOSS discoveries is also astonishing and shortly we will be able to let you know about a paper recently submitted to the Astrophysical Journal (with our names attached to a long list of professional astronomers!!! Wow) that has significant implications for Supernova types, maybe even rewriting the textbooks!
It just gets better and better.
Peter, that's wonderful. It makes us proud just to know you guys.
New Zealand the land of the long white cloud? I don't think so!
The sky above BPO has been completely clear (100% photometric) more than 80 nights since the end of March. Maybe more than 90. I'll have to check the ASC record. But whatever the case, it's certainly been a great run of weather, and shows no sign of ending any time soon.
Hi All,
Thank you so much for all your great comments. It is always fun to read what everybody has to say.
I don’t post on here that often mostly as I am either on the farm or blinking images or imaging galaxies but the Guys do a great job keeping every one informed.
Well, I have been hardly been able to take a breath in the last week or so. The lack of sleep and busy at my day job has made things rather challenging.
One thing people must remember we are just having a good run at the moment. I wish SN hunting was this easy but it isn’t. We have had long breaks between discoveries. For some reason we are just having a good run...long may it continue .
It is alot of fun to work with Greg,Pete, Colin to get things done ASAP before someone else gets the discoveries .
Many thanks mist go to Greg who has been fantastic this week. As he said the emails that fly back and forth are very hard to keep up with. Actually at one stage I had to stop and think what I was sending for which discovery.
This lasts one sounds very interesting and contributing to that is rather cool.
Attached is my first image pretty poor but you get the idea.
Well done Stu, and the BOSS team, I am in awe as to your success.
Great team work is obviously paying off in spades
Not much chance of getting a look at this latest one for me ,much too faint.
Keep 'em coming. 
