Object name: NGC5972
As most know by now I like to go where most amateurs fear to tread. Back in the fall of 2008, it was announced that a Dutch school teacher, Hanny van Arkel, looking at Galaxy Zoo images saw something odd. Hundreds had looked at the same image before her but she was the only one to wonder "What's that?" and post the question. It turned out to be a green object outside the obscure galaxy, IC 2497. It was bright green though on the Sloan images it was blue. At the time it was a mystery. Fortunately, the moon was out of the sky and it was well placed so I gave it a try to see if I could pull it out. Digital imaging was still new to me and I wanted to test its limits. It turned out to be relatively easy, not a difficult test after all. Still, it became the first amateur image of it as far as I and Hanny could determine. A check of Google images fails to turn up an amateur image of it even now. Though it misses many posted to Flickr and the like. Still, it surprises me a unique but rather easily imaged object is so ignored by most amateur imagers. It was later determined to be a cloud of mostly ionized oxygen illuminated by a now faded QSO in the heart of the galaxy, possibly left over from something IC 2497 digested. Were there others? Galaxies devour their kind constantly so it seemed likely.
Related Designation(s):2MASS J15385414+1701343, 2MASX J15385414+1701344, 2MASXi J1538541+170134, ASK 692256.0, CGCG 107-018, CGCG 1536.6+1712, GALEXASC J153854.16+170133.9 , GALEXMSC J153854.23+170132.7 , IRAS F15366+1711, LQAC 234+017 007, MCG +03-40-016, NGC 5972, NGC5972, NSA 166342, NVSS J153854+170137, PGC 055684, SDSS J153854.16+170134.2, SDSS J153854.16+170134.3, SDSS J153854.17+170134.2, UGC 09946, USGC U715 NED03, UZC J153854.2+170134, [TTL2012] 478375, [VCV2001] J153854.2+170133, [VCV2006] J153854.2+170133,