I need help with a possible supernova detection please!

Affiliation
American Association of Variable Star Observers (AAVSO)
Sat, 12/09/2017 - 06:49

Thank you for reading this, I'm not very experienced I'm sure it's something I did wrong, or made a mistake or a false alarm but anyways I was pretty picture imaging NGC2175 a yesterday with my C14  piggybacking scope a William Optics 61mm and ASI1600MM with a Lum filter at 300 seconds cadence and I just blinked through them and at about 3AM a very bright star appeared and then dissapeared . I'd like to send the raw images to some of you experts or maybe get some advice on how to possibly report this..

Listen I'm sure it's a false alarm or some problem with the camera, but I need you experts to look at the subs..

Thank you in advance and if it's a false alarm , I apologize for the excitement :-)

Pablo Lewin

PS I was also imaging with the C14 but the FOV was too narrow and didn't catch anything..

Affiliation
American Association of Variable Star Observers (AAVSO)
The images are now on Vphot so I can share...

I uploaded the images to vphot, the one before, during and after, 300s exposure, LUM..so I can share with those who might be able to help me identify this event..I don't even have to tell you the RA and DEC of the event..you'll see it clearly without any help..

Thanks.

Affiliation
American Association of Variable Star Observers (AAVSO)
sharing

Hi Pablo,

Go ahead and share to HQA.  It won't be a supernova, as those last for months, but there are several other possibilities.

Arne

Affiliation
American Association of Variable Star Observers (AAVSO)
Thanks Arne, shared!

Thanks Arne, shared!, the images are calibrated even though the "Cal" shows red (I don't use Maxim DL)... the object is at RA  06 11 28 and DEC 20 15 51.. what the hell is it??

Affiliation
American Association of Variable Star Observers (AAVSO)
The reason for no airmass on those images..

Arne , Ray and Ken the reason the airmass is not showing on Vphot is as follows. I use two instances of Sequence generator pro to sequence both cameras, the main instance has all the necessary info, such as location coordinates,RA and DEC of target..well everything necessary for the main scope (c14) , the piggy back scope is a 61 mm doublet with an ASI1600MM attached and I use it to get wide field images of objects, no photometric filter on that one just LUM,HA.OIII and SII..so I didn't program anything on that instance other than sequence info, target name and equipment, barebones ..I will change that soon but that's the reason you see 0.000 airmass..I have the airmass info on the main scope and I was imaging with that one concurrently..in case you need it..

Affiliation
American Association of Variable Star Observers (AAVSO)
image inspection

The offending object is around pixel (1356,1953) on the 2nd image.  Looking at it, the object profile does not look stellar.  There is a trail into and out of the image, which could be bleeding in the detector, though this is a CMOS device and bleeding is not common.  There is no hint of the object on the frames before and after, so the event duration has to be 300 seconds or less.

My guess is that the non-stellar profile is more likely a plane navigation light that happened to blink while the plane was passing through your field of view.  There are no underlying stars, so the event, if stellar, would be many magnitudes, an unlikely event.  Some flare stars show many-magnitude events, but they last for ~15 minutes.

If you see it again, let us know. :-)  Nice-looking image, BTW - it looks like this 16Mpix camera has promise for photometry.

Arne

Affiliation
American Association of Variable Star Observers (AAVSO)
Thank you Arne!

Well false alarm then , to the untrained eye (mine) it looked amazingly like a SN! What I could do since I have a personal ADS-B receiver and an account with Flightware is to check what flights flew over my house at that time of the morning...what threw me was that it was round and there was no trailing other than the two handles that looked like blooming from a pro camera (the ASi1600MM CMOS I believe has anti-blooming protection)...

Oh well, science prevails, False alarm..thank you Arne!