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View Full Version : Object of the Week - March 19, 2017 - NGC 2903



Paul Alsing
March 20th, 2017, 11:05 PM
Object of the Week - March 19, 2017 - NGC 2903 = UGC 5079 = MCG +04-23-009 = CGCG 122-014 = PGC 27077 - LEO
R.A.: 09h32m09.7s Dec.: +21°30'03" (2000)
Size: 11.5'x 4.2'
Mag; V = 8.9

Big, bright and beautiful, and perfectly placed for this time of the year from just about anywhere on the planet. Even from the south end of the south island of New Zealand it almost reaches 2X airmass at its highest altitude.

NGC 2903 is a barred spiral galaxy about 20 million light-years away in the constellation Leo. It was discovered by William Herschel who cataloged it on November 16, 1784. It is hard to understand how Charles Messier could have possibly missed this guy, when 3 of Messier's comets came quite close to it. A comet in 1760 passed it the night of March 11-12 in 1760 (less than 2° away), and his comets of 1762 and 1771 were nearby!
Here is a spectacular APOD;

https://apod.nasa.gov/apod/ap150410.html

In the eyepiece NGC 2903 is among the best galactic eye-candy available. Although the 2 main spiral arms are not of the in-your-face-M51 variety, they are nevertheless easy enough to see, especially out near the edge where they start to separate from the core. There is a large and faint knot in the NE or NNE edge (averted vision only for me), which is sometimes called NGC 2905, but it seems to me that most sources just say that NGC 2905 = NGC 2903. I attempted to query the NGC/IC Project page but apparently that site is no longer with us. Steve G, what's up?

As I always tend to do, I like to look around and see what else might be in the neighborhood, and about 40 arcmin to the ENE is NGC 2916, a 12.7 mag Sb spiral galaxy, and about 35 arcmin to the WSW is a sprinkling of very faint, very small galaxies, of which I believe I glimpsed 2 (MCG 4-23-5 & MCG 4-23-6), these being in the mag 15-16 range, on a good night a couple of years ago. Hey, they were there, and I have a 25", so I tried! Wouldn't you?

Here is a screenshot from SkyTools 3 showing the NGC 2903 area, and the black circle is just a 30 arcmin reference, for scale...

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I looked for, but didn't see, UGC 5086, and assume that it has a really faint surface brightness.

As always, give it a go and let us know

AKE
March 21st, 2017, 04:32 PM
After almost three years of beeing registrated here (and much longer lurking around) I'll bravely do my first post now, ha.

I saw this galaxy on March 4th 2006 for the first time - and immediatly hated it, because I spend two hours or so looking for it. I just was too stupid to handle that damn starfield around Leo's head. A big, diffuse, oval cloud without any details appeared in the eyepiece, no matter which one of my former telescopes I used (4,5" and 10"). This appearance (and the fact, that NGC 2903 was my unchallenged most-hated object) hadn't changed for long years, and for a long time I also had no motivation to look for it again... better things to do.

Two years ago I found myself under a dark, alpine sky (1.500m/ 5.000ft) with my 16". In a weak moment I didn't know what to do else and suddenly headed to NGC 2903. Surprise 1: feared search took only ten seconds. Surprise 2: So much details. A bright bar with a brighter, flat core, two spiral arms in the south and one in the north. Both segments are connected by a stronger pronounced eastern edge. Bar doesn't reach the halfmoon-shaped bend of the northern arm, there is a darker space between.
https://image.jimcdn.com/app/cms/image/transf/none/path/s8c49ece990fe9984/image/id18f4e47d14db9b9/version/1490113337/image.jpg
Of course, there is more structure reachable in 16"-mirrors, but it was enough for me to make peace with 2903.

wvreeven
March 21st, 2017, 05:46 PM
Fantastic first post! Glad to read you made peace with this beautiful galaxy!

Strange though that you didn't see any details in the 4.5" or even the 10". I have seen the bar and a start of the arms in my 6" many years ago. Then again I didn't see as many details in my 20" as you did in your 16" so I'll most definitely need to revisit it soon.


Clear skies, Wouter

Uwe Glahn
March 21st, 2017, 07:28 PM
Hi Anne,

welcome to deepskyforum and excellent first post.

I had the chance to observe and sketch this galaxy from La Palma under extremely good conditions from the top of the Roque de los Muchachos. Like Anne this galaxy was not my best friend in the past and up to now my opinion is that all details are still difficult to detect and need time to resolve. But when it can be resolved it is a fantastic sight.

14.5", 202x, NELM 7m5+ (ORM-La Palma), Seeing III
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Howard B
March 23rd, 2017, 09:04 PM
Wonderful choice of object Paul, and a great first post Anne. I've had a few good observations of 2903 but have seldom had the time to do a decent sketch because clear spring nights are so rare in western Oregon.

The first is a quick sketch made with my 28 inch scope a few years ago:

2511 2512

"High clouds are flying through so this was hardly a pristine view, but more than enough to sketch! Bright core, long bar, several spiral arms - all nice and bright too. 253x was best but 408x brought out more detail. Partly cloudy, no SQM."

The second observation was made with Jimi's 48 inch scope"

2513 2514

My notes are part of the sketch - hope you read my hand writing - because the more I looked the longer the outer spiral arms became. This must have been the trip I forgot my SQM at home but I'll guess the sky was in the 21.5 to 21.7 range.

One of my observing goals is to make as detailed a sketch of 2903 as possible with my 28 inch under a really good sky, but it doesn't look like that will happen this year. We've had the worst winter weather in my memory and spring isn't shaping up any better. I haven't had my scope out since October - hope everyone else is doing better!

RolandosCY
March 28th, 2017, 07:56 AM
NGC 2903 was a superb galaxy even in 120mm of aperture last Saturday night. Observing under SQM21.6 skies with superb transparency and steady seeing I could detect parts of the arms, though the bar was not so distinct...

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Dragan
May 5th, 2019, 02:31 AM
https://mashable.com/article/nasa-hubble-spiral-galaxy-photo/

Hubbles latest take on 2903

Paul Alsing
May 6th, 2019, 05:00 AM
Amazing photo, Dragan, thanks for posting...