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Bright transient in M74 - PSN J01364816+1545310

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Bright transient in M74 - PSN J01364816+1545310

I'd like to draw attention in this forum to Elizabeth Waagen's post over in the "Campaigns" forum.

Its magitude 12.4 in M74.

Good hunting!

Robin Leadbeater
PSN in M74 spectrum

A spectrum by amateur Paolo Beradi.

GELATO suggests a type II supernova but no obvious H alpha yet



I would not give up yet.  It

I would not give up yet.  It needs more signal.  I'd suggest a longer exposure at lower spectral resolution.  The structure between 5000-6000AA does not fit either template but its not clear if that is real or not.  The Star Analyzer might work for this one.

Robin Leadbeater
reporting spectra

Yep a straightforward target for the Star Analyser provided it can be isolated from the background Galaxy. ALPY 600 in slit mode would probably be better.

Can you advise Paolo (and others)  on how and where best to report these  follow up  spectra?

CNY's picture
SN in M74 a type II

It looks like we have a type II

Reporting SN spectra


Here is the advice I have for anyone trying to "beat the pro" to get that supernova spectrum reported first.  There are two options:

1) The CBAT TOCP has a page for "How To Report Discoveries" (link below)  The instructions are pretty detailed.  People who already are reporting follow-up photometry can report spectra almost the same way.  I know it can try one's patience to try to get through this procedure in a panic, so I'd suggest that anyone who wants to do this through CBAT should sit down and read through this in advance of trying to "beat the pro."  That said, I also don't like to throw a ream of instructions at people as an asnwer, so I am personally willing to guide and help any AAVSO member as they attempt to navigate this process, taking on a lot of the blame while letting them get all the credit (my direct email is at the end of this message).

Here is the link to the "How To Report Discoveries" page:

2)  As demonstrated in the case of this SN in M74, the other route is ATEL (Astronomer's Telegram).  I know not everyone has access to ATEL but I am willing to use my access to submit a report on behalf of any AAVSO member who has something important to report.  I'd ask that you write most of the text, but I'll happilly take all the blame while you take the credit.  I did this for Terry Bohlsen when he got a spectrum of 2009ip last September (see

 I'm not going to give my phone number out so you guys can wake me up in the middle of the night to do this. :)  But I do read email pretty regularly and I am suscribed to get the AAVSO spectroscopy forum emailed to my mailbox as things are posted.  So you can either email me directly (jmart5 _at_ or shout for help here if you want pro assistance with either approach.

You got pretty close to beating the pros this time.  Its just a matter of time until someone breaks through.

Robin Leadbeater
sn spectroscopy projects


You got pretty close to beating the pros this time. 


The main interest is in potentially supporting amateur discoveries as I understand talking to amateur sn hunters is it is getting more difficult to get pro telescope time to get confirming spectra.  Around mag 15-16 is doable with modest aperture to give a lower resolution spectrum suitable for a preliminary classification  but  breaking into the mag 17 and fainter region where most amateur discoveries are made is likely to need >0.5m aperture and a good site.  The other interesting area is in long term follow up, for which this target should be a good candidate. eg as here  for sn2011fe  which was followed for 5 months




Robin Leadbeater
beating the pros

Actually Paolo's spectrum is 14 hours earlier than the one reported in ATEL 5228 and correctly identified the type and the same best fit using GELATO. It was also reported here and on the ARAS forum before the ATEL was issued so one to us :-)


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