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bright SN2013dy in NGC 7250 Lac

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#1 nytecam

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Posted 23 July 2013 - 05:30 PM

My est [unfiltered] 12.6 from tonight - pic below :grin:

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#2 Hubert

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Posted 24 July 2013 - 07:01 AM

Hope it gets somewhat brighter. I'm waiting for clear weather for a visual observation.

#3 John_G

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Posted 23 August 2013 - 11:34 AM

I had a look at this supernova on Aug 11. Easily seen with my 200mm. From what I've read, astronomers use these Type Ia supernova as a 'standard candle' to calculate the distance to the galaxy. Would this have been done for NGC 7250?

#4 StupendousMan

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Posted 23 August 2013 - 12:56 PM

This galaxy is close enough (distance modulus around 30.7, so a distance of around 14 Mpc) that we _could_ measure its distance in several ways: via Cepheids (with difficulty), the globular cluster luminosity function, the tip of the red giant branch (with difficulty), the planetary nebula luminosity function. It's a bit surprising to me that the only distance listed in NED

http://ned.ipac.calt...&extend=no&a...

for this galaxy is based on the Tully-Fisher technique. I guess there are just a LOT of galaxies in this distance range out there, and no one has cared about NGC 7250 enough to put it near the top of the list.

This SN will probably encourage someone to use one or more of the methods listed above to determine its distance more carefully.

#5 nytecam

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Posted 24 August 2013 - 04:28 AM

This galaxy is close enough (distance modulus around 30.7, so a distance of around 14 Mpc) that we _could_ measure its distance in several ways: via Cepheids (with difficulty), the globular cluster luminosity function, the tip of the red giant branch (with difficulty), the planetary nebula luminosity function. It's a bit surprising to me that the only distance listed in NED

http://ned.ipac.calt...&extend=no&a...

for this galaxy is based on the Tully-Fisher technique. I guess there are just a LOT of galaxies in this distance range out there, and no one has cared about NGC 7250 enough to put it near the top of the list.

This SN will probably encourage someone to use one or more of the methods listed above to determine its distance more carefully.

Gxy dist = ~530MLY according to z=0.003889 in your reference above ;)

#6 Rich (RLTYS)

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Posted 24 August 2013 - 06:59 AM

Took this image on 8/19/13 of SN 2013DY. I estimated its mag at 13.7

Rich (RLTYS)

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