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Object of the Week, November 8th, 2015 - NGC 925 in Triangulum
Object of the Week, November 8th, 2015 - NGC 925 in Triangulum
NGC 925 = UGC 1913, MCG 5-6-45, PGC 9332
R.A.: 02h27m16.9s
Dec.: Dec.: +33°34'44" (2000)
Size: 10.5' x 5.8'
Mag: 10.60 B
Hubble Type: SBcd
I observed NGC 925 this past Saturday night under SQL 21.3 skies from my local Anza Borrego State Park, which is about as good as it gets there, being only about 60 miles east of San Diego at an altitude of about 2500 feet. The seeing was much better than usual and I was able to split several stars that had less than 2" separation.
Attachment 1869Attachment 1870
Although NGC 925 has an integrated magnitude of about 10.6, it has a much lower surface brightness, slightly less than mag 15, so it is quite dim. NGC 925 is a barred spiral that appears to be nearly face-on. My first impression was "Wow, this guy is dim", but after spending a few minutes I was able to tease out a lot of detail. I used my 13mm Ethos, and later used my Harry Siebert 6.2mm eyepiece. This galaxy features a diffuse bright bar that hints at what I assume to be HII areas. I could not see either of the 2 arms as depicted in photos, but in Debbie's 20" dob I detected them as large puffy 'wings' with rounded edges. At first these wings were uniformly gray stains on the sky, but after spending perhaps 10 minutes observing, and adding image scale with the 6.3mm, I began to see subtle variations throughout the area, the classic 'mottling' that we all experience, and after checking my observations with a photo I have determined that the brightest parts I was seeing were just south-southeast of the bar and also to the northwest of the bar. I can't say that I saw any specific HII area, but I definitely suspected several.
Taking a labeled screenshot of the galaxy with me up to the eyepiece, I tried but failed to detect 2 extremely faint companion galaxies, LEDA 2034970 and LEDA 2034188, but with each being mag 17+, it was a futile exercise. But, I always try, what the heck, sometimes even a blind squirrel finds an acorn...
The big event of the night was the launching of a test missile of some sort, just off the coast of San Diego, and near the end of astronomical twilight. We saw it from just after launch until it disappeared over the western horizon. It started off as an orange streak across the sky, after rising from beyond a hill, and when the second stage lit off there was suddenly a large blue spherical cloud, which later developed several shells that eventually got to be over 100º across and extended from the horizon to past the zenith! The blue cloud persisted for maybe 15 minutes, long after the missile itself was gone, and eventually just faded away. I've never seen anything like it, it was spectacular! 6 or 7 minutes after first seeing this rocket we all heard the rumble from its launch, which puts that event perhaps 70 or more miles away.
As always, give it a go and let us know!
