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Supernova in NGC1637...
an independent discovery

On October 29,1999, I set up to do my supernova search program at the observatory at Plettstone. Just before midnight, my automated scripts and robotic mount finished their work.  I had collected data on some 50 galaxies. The moon was scheduled to rise shortly and I had still enough time to shoot a couple more galaxies. I always enjoy the time when I can personally interact with the systems.  
I have the opportunity to determine the exact parameters for how I will shoot a deep sky object.

The first galaxy I chose was too close to the meridian for adequate exposures, so I moved to the second target. A thumbnail of the galaxy (by the Palomar Observatory) served as my reference shot. This is a barred spiral galaxy in the constellation of Eridanus.

Reference image courtesy of Software Bisque
As the data downloaded from the first of 70 exposures, I gasped as I looked at what most people would consider a very boring image with very little detail. (Many images we see, including that on this page, are created by "stacking" several lower quality images.)   Even though it was cool out, I flushed warm with delight.  

My original discovery image (reduced)

 
I had discovered a supernova! A single star stood out just to the right of the galaxy core... a star not visible on the reference shot.
A loud "YeeYow" echoed down through the valley! This was a major milestone in my life.  I had to settle down though.  You see, I've learned that a single data set doesn't prove anything. Some Digital Sky Survey reference pictures obscure close stars with overexposure for example. And there have been two cases where I had false readings due to equipment limitations. 

I imaged the galaxy over the next hour to collect enough data to compose the image we see here.
Supernova 1999em appears to the upper right of the galaxy core.

ST7 camera, C11 at F6.3, 20 one minute exposures at bin2 were stacked for the luminance layer. 5 one minute exposures at bin 3 in each RGB channel were stacked for the color. Image processed in MaximDL and Adobe  photoshop.

 With each data set I combined, the star became better defined. As soon as I arrived home on Sunday, I checked previous  observations on the web for the galaxy NGC1637. I frantically searched for the supernova detection site as I reviewed shot after shot of this galaxy.  Indeed, I had discovered a supernova!
Lick had also discovered the same supernova the same evening. I submitted my data just in case.  Due to the timing of the submission, my data has been  accepted  as an independent discovery. At face value, it means that I don't get my name on the discovery. However to my own satisfaction, I was the first to actually see with human eyes the ancient light! And my data has been submitted and accepted for use in evaluating the supernova.  My data support a magnitude of 14.25 while that of Lick Observatory is 13.5. 
This has been classified as a type II supernova, a likely candidate for a soon to be black hole.  I'm sure that the large observatories will be keeping track of this event  to see the story unfold.  So will I.