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Charlie Hein
Postmaster
Reged: 11/02/03
Loc: 26.06.08N, +80.23.08W
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What’s Up Perseus (2)
#5657654 - 02/02/13 07:32 AM
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What’s Up Perseus (2)
By Steve Coe
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David A Rodger
professor emeritus
Reged: 08/12/03
Loc: North Vancouver, BC, Canada
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Re: What’s Up Perseus (2)
[Re: Charlie Hein]
#5659635 - 02/03/13 09:56 AM
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Hi, Steve. With respect, I'd suggest that both the Crab nebula (M1) and the Owl (M97) seem fainter than M76 to my eyes. With an OIII filter I have little difficulty seeing the two components of M76 in my TeleVue NP-127 refractor, whereas M1 and M97 elude me. I'm observing from a light-polluted city sky, however, and I've seen all three easily from our dark-sky site about an hour's drive east of North Vancouver. I wish I had your Arizona sky!
David
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stevecoe
"Astronomical Tourist"
Reged: 04/24/04
Loc: Arizona, USA
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Re: What’s Up Perseus (2)
[Re: David A Rodger]
#5660979 - 02/04/13 12:20 AM
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David;
I was using the magnitudes as given by professional data. I know that is not the best for visual observing, but it is what we have. There is no scientific value for determining visual magnitudes, so unless a very wealthy amateur decides to take on providing that data, we are stuck with the numbers from the pros.
If you get a chance to make it down to AZ, we would love to have you come out and observe with us.
Clear skies;
Steve Coe
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David Knisely
Postmaster
Reged: 04/19/04
Loc: southeastern Nebraska
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Re: What’s Up Perseus (2)
[Re: Charlie Hein]
#5666097 - 02/06/13 09:54 PM Attachment (20 downloads)
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Steve Coe wrote:
Quote:
NGC 1023
For some time I owned a Celestron 9.25" SCT and I quickly found the observations I made with it were very similar to what I had seen in my Nexstar 11 GPS from years ago. But, one of the objects I did observe with the 9.25 inch was NGC 1023, a galaxy. With a 14mm eyepiece it was pretty bright, pretty small, elongated 2.5X1 and much brighter in the middle. Averted vision makes it larger and more prominent.
Using a 13.1" f/5.6 on a terrific night (S=8 T=9) over 100 miles from Phoenix this galaxy shows lots of internal detail. At 100X it is bright, large, very elongated 3X1 in PA 90 and much, much brighter middle. Raising the power to 220X brings out several brightenings in the outer arms (stars or H II regions?). Averted vision makes a huge difference in the length and thickness. The higher power also shows a very faint companion to the east.
Unfortunately, NGC 1023 doesn't really have much in the way of spiral detail. It is an SB0 galaxy and, other than a star-like nucleus and a well defined slightly brighter inner core region, does not show spiral arms. Even in my 14 inch Newtonian, the outer haze is fairly smooth in texture with no detail seen. The only exception is the very faint (14th magnitude) diffuse companion galaxy NGC 1023a which sits along the east-southeastern edge of the galaxy about 2.6 arc minutes east-southeast of NGC 1023's nucleus (P.A. 99 deg.). It appears as a very diffuse faint brightening which might be mistaken for a spiral arm if someone didn't know about it. There are no other nearby galaxies to NGC 1023 except for the 17th magnitude PGC 10169 which sits next to an 8th magnitude star (SAO 55779) east of NGC 1023. Below is an image Minnesota astrophotographer Rick Johnson took of the object in his 14 inch LX200R:
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