Hello, I was observing a couple of nights ago and looking at open clusters. The name of NGC 2420 caught my eye..."the twinkling comet" cluster.
I added that to my target list for the night as it sounded interesting and I wondered what that was all about.
The moon was up and fairly bright so I was only getting the brighter stars in this cluster....but then I saw what appeared to be a little fuzzy ball in the group....next to another star - almost looking like a fairly widely separated double star except the fuzzy "comet" was maybe 2 1/2 times as large as the nearby star.
As I was looking at the fuzzy ball it faded right out to blank... and a few seconds later it was back. I stared at this thing for almost ten minutes because "mind blown" It just kept disappearing and reappearing every few seconds. Not fast, but slowly. I think I discovered the "twinkling comet" within this cluster.
My research led me to a description of the "blinking nebula" which basically said it is sort of an optical illusion where by the star nearby (or within - in the case of the blinking nebula) is in just the right proximity to cause sort of a night vision blindness and the fainter object (or the nebula) blinks in and out as your eyes move while observing the object.
I thought this was extremely cool. Way fun. I see a lot of astrophotography of this cluster, but I could not find any reference to the blinking comet or anyone talking about it, except for the name of the cluster itself. I am pretty new at astronomy and observing so I had a few questions that I wanted to throw out there.....
1) Is the small fuzzy ball object actually a stationary comet? (I thought comets moved)
2) If it is not a comet, what is it? ( a small globular?)
3) Has anyone seen and experienced the 'twinkling comet' in this way?
-Lauren (viewed in 8 inch Dob, Bortle 4.5 sky, 50% moon out, ES 14 82deg EP )
Edited by Sky_LO, 15 March 2019 - 08:23 PM.