Supernova in M51 (the Whirlpool Galaxy in CVn)

[Eroica]

A new supernova (SN 2005cs) has exploded in to view in the famous M51 or "Whirlpool Galaxy", which is in Canes Venatici, just off the end of the 'handle' in the Plough.

When discovered from Germany on the night of June 28/29 it was about magnitude 13 meaning you'll need at least an 8-inch telescope to see it, although the galaxy itself at 8th magnitude can be glimpsed in 10x50 binoculars.

SN 2005cs (http://www.astrosurf.com/snweb2/2005/05cs/05csHome.htm)

[Minbari]

oooo, that be nice 2 c, shame the ETX can't cut it till I get a good CCD imager on it.

Can you post a pic?

[Kullat Nunu]

Again?! It's only 11 years from previous one (SN 1994I).

(Waiting anxiously for the next visible supernova in the Milky Way.)

[ngc3314]

A new supernova (SN 2005cs) has exploded in to view in the famous M51 or "Whirlpool Galaxy", which is in Canes Venatici, just off the end of the 'handle' in the Plough.

When discovered from Germany on the night of June 28/29 it was about magnitude 13 meaning you'll need at least an 8-inch telescope to see it, although the galaxy itself at 8th magnitude can be glimpsed in 10x50 binoculars.

SN 2005cs (http://www.astrosurf.com/snweb2/2005/05cs/05csHome.htm)

My brain seems to have just recovered from our Deep Impact event with a couple of hundred spectators, or I would have wondered about this before. Now that this looks like a Type II SN, the odds must be pretty good that the progenitor star showed up in the HST ACS images taken for the big Heritage release. Anybody know how that is working out, or whether we'll have to wait for it to fade a bit and get matching ACS images to know the position accurately enough?


[Edit a few hours later - I just learned that HST images are scheduled for July 11, and should give a really good position for the supernova to compare with the "before" data. With any luck, we'll soon double the number of SN for which we know the luminosity and color of the progenitor star.]

[ngc3314]

(C,'mon, c'mon. I can beat him in linking...)

There is indeed now an HST identification (http://hubblesite.org/newscenter/newsdesk/archive/releases/2005/21/image/a) of the progenitor of supernova 2005cs in M51. Red supergiant somewhere around 10 solar masses, didn'tt blow as much away in winds as Sanduleak -69 202.

[Blob]

Title: Ruling out a massive-assymptoic giant-branch star as the progenitor of supernova 2005cs
Authors: J.J. Eldridge, S. Mattila, S.J. Smartt

We calculate the predicted UBVRIJHK absolute magnitudes for models of supernova progenitors and apply the result to the case of supernova 2005cs. We agree with previous results that the initial mass of the star was of low, around 6 to 8 M(sun). However such stars are thought to go through second dredge-up to become AGB stars. We show that had this occurred to the progenitor of 2005cs it would have been observed in JHK pre-explosion images. The progenitor was not detected in these bands and therefore we conclude that it was not an AGB star. Furthermore if some AGB stars do produce supernovae they will have a clear signature in pre-explosion near-infrared images. Electron-capture supernovae are thought to occur in AGB stars, hence the implication is that 2005cs was not an electron-capture supernova but was the collapse of an iron core.

Read more (http://arxiv.org/PS_cache/astro-ph/pdf/0701/0701152.pdf) (42kb, PDF)