Alright Vulcan59, you got me really interested in this... I'm a complete amateur and sorry if this is long and irrelevant, but here's some things I've found.
Using the listed right ascension and declination values, I decided to see if any of our 2011 supernovas were around the area of Leo.
Given this list of stars in Leo _http://en.wikipedia.org/wiki/List_of_stars_in_Leo I found that the one listed as 2011J or the "Jth" (10th) one was in the region of Leo.
"2011J Anon. 2011 01 08
10 50.7 +28 01 1N 18.8"
I'm pretty sure they have the apparent magnitude listed under "mag." (far right number in what I have listed)
Based on the info here... _http://en.wikipedia.org/wiki/Apparent_magnitude#Table_of_notable_celestial_objects ...you can get an idea of the magnitudes involved.
From the full list of recorded supernovae _http://www.cbat.eps.harvard.edu/lists/Supernovae.html:
"1987A 1987 02 24 05 35.4 -69 16
4.5"
_http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit3/supernova.html
Supernova 1987a
Nearest naked-eye visible supernova seen since 1604.
Explosion occured on February 23, 1987:
* 15 Msun Blue Supergiant Star named SK-69o202 exploded in the Large Magellanic Cloud (a satellite galaxy of our Milky Way located some 50,000 pc away).
* Particle experiments on Earth recorded a pulse of neutrinos arriving just before the burst of light from shock breakout.
* Astronomers have continued to follow its development over the last 15 years.
SN1987a has provided us with a great wealth of information about supernova physics, and help to largely experimentally confirm the basic predictions of the core-bounce picture (although with good data, many details
still remain murky).
But that doesn't mean the value is any indication of their "intrinsic brightness":
From the list:
"2006gy NGC 1260 2006 09 18 03 17.5 +41 24 2W 0N
15.0"
_http://www.nasa.gov/mission_pages/chandra/news/chandra_bright_supernova.html
The star that produced SN 2006gy apparently expelled a large amount of mass prior to exploding. This large mass loss is similar to that seen from Eta Carinae, a massive star in our galaxy, raising suspicion that Eta
Carinae may be poised to explode as a supernova. Although SN 2006gy is intrinsically the brightest supernova ever, it is in the galaxy NGC 1260, some 240 million light years away. However, Eta Carinae is only about 7,500 light years away in our own Milky Way galaxy.
"We don't know for sure if Eta Carinae will explode soon, but we had better keep a close eye on it just in case," said Mario Livio of the Space Telescope Science Institute in Baltimore, who was not involved in the research. "Eta Carinae's explosion could be the best star-show in the history of modern civilization."
and...
_http://www.berkeley.edu/news/media/releases/2007/05/07_supernova.shtml
Unlike typical supernovas that reach a peak brightness in days to a few weeks and then dim into obscurity a few months later, SN2006gy took 70 days to reach full brightness and stayed brighter than any previously observed supernova for more than three months. Nearly eight months later, it still is as bright as a typical supernova at its peak, outshining its host galaxy 240 million light years away.
UC Berkeley post-doctoral fellows Nathan Smith and David Pooley estimate the star's mass at between 100 and 200 times that of the sun. Such massive stars are so rare that galaxies like our own Milky Way may contain only a
dozen out of a stellar population of 400 billion.
I'm having a hard time finding out how far the supernovas are in light years away. And from the looks of it, it
may be hard to tell.
In a paper titled "How certain is the distance to the most luminous supernova?" it appears there is some question about the quoted distance in the above two articles.
http://arxiv.org/abs/0709.4100
I found another source for locating them in relation to constellations. _http://pp3.sourceforge.net/#section2
I will play around with this when I have time as it looks rather complicated, but it seems like an interesting
tool nonetheless.
I'll dig around and see what else can be found. :)
