In 1994, while working through the 400 objects required to earn my Herschel 400 Certificate, I made an observation that didn't excite me until nearly five years later. Here's how it happened.
|Supernova 1994D as imaged by the Hubble Space Telescope in mid-1994.|
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My logbook reflects my curiosity about a dim star-like object that appeared very close to the nucleus of this galaxy’s elongated disk. My entry reads: “Easily identified by a pair of 7th magnitude stars either side; Elongated, w/condensed nucleus, and a 12-13 magnitude star just off to side; resembles a SN”. SN are letters which I usually use to abbreviate the word supernova, and on this particular evening, it was an accurate description, although I wouldn’t realize it for nearly five more years. Some other information I recorded that evening was that I was using my trusty Meade 826 8” f/6 Newtonian with an Erfle 20mm eyepiece yielding an even 60x. The night was very good and I rated it a 4.5 on a scale of 1-5. I also logged the time that I came across this galaxy at about 11:09 p.m. I mentioned a second galaxy being in the same field-of-view with 4526 with its designation of NGC-4535. I listed it as, “Larger than 4526 above, just under 1 degree N. Appears much fainter (spread out) No condensation; virtually no elongation”. These two objects are very typical of how I logged so many other objects, with one larger or brighter than the other, with one nucleus brighter than the other, etc. But what was important on this particular evening was how much the little star near the nucleus of 4526 resembled a supernova.
In late 1998, I came across an image of galaxy NGC-4526 taken by Hubble Space Telescope on the Astronomy Picture of the Day (APOD) website. As they always do, Robert Nemiroff and Jerry Bonnell wrote the text accompanying the image and pointed out that this galaxy had been imaged while a supernova had been present near the nucleus. The exploding star in that galaxy that gave rise to this brilliant supernova had exploded many millions of years ago, but the light from it hadn't reached Earth and been seen until mid-June of 1994. Seeing this image, for some reason, caused that moment of epiphany where I recalled that night 4 ˝ years earlier when I’d seen a supernova-like object in some obscure galaxy that I’d long since forgotten the designation of.
Thankfully, I’d had those logged observations that I could return to and see if by some chance I had seen this particular supernova. As I located the entry for this object, there was my impression of a “star” and my description, “…resembles SN” near the center of that galaxy that evening. I had recorded my own impressions of a possible supernova almost 4 ˝ years earlier, and my logs had helped give me the proof of that which I needed in order to confirm this personal discovery.
My Messier certificate had taken me just over 2 years to complete, and nearly half of the first year’s entries had been made while I borrowed someone else’s telescope. My Herschel list had taken me almost 6 full years to complete. But as important to me as the fact that I’d completed these lists were, my observation and mention of a star near a faint galaxy’s nucleus was at least as memorable as working these entire lists had been. I can never see this Hubble image of Supernova 1994D again without remembering that night when I’d logged my observation, and had indeed, made my own supernova discovery.