by Joe Stieber » Wed Apr 27, 2016 7:34 pm
Visual_Astronomer wrote:Omega Centauri is one of the most spectacular objects in the sky for the visual astronomer. Make an effort to view it, even if all you have are binoculars. It is worth the effort!
I agree with you entirely, except not everyone is geographically located in a favorable position to do so. Omega Centauri has a declination of 47.5° south, so it's position is more favorable to observers in the southern hemisphere. At a latitude of 40 degrees north, which cuts across the middle of the United States, Omega culminates just several degrees above the southern horizon (including a little boost from atmospheric refraction). Therefore, it's difficult to see, let alone see well, because of considerable atmospheric absorption down that low (even on nights with nice clear skies overhead, it's often murky near the horizon). As a result, it's a challenge just to spot Omega from 40°N, although I've heard of observers seeing it from Long Island, NY, and the north shore of Lake Ontario.
I've seen Omega a number of times from East Point, NJ (
the site of the APOD for January 8, 2012), on the north shore of the Delaware Bay (at 39.2°N latitude). When sky conditions permit, it's visible in binoculars, but typically, it's not really outstanding. On one lucky occasion (January 31, 2008), when transparency was unusually good over the bay, Omega was spectacular in my 16x70 binoculars, better than globular clusters M4 and M13 at the same time, which were at much higher altitudes. I've been trying to spot Omega for a while now from Coyle Field, an observing site closer to central NJ (at 39.8°N), but so far, I haven't had a definitive sighting yet.
Of course, the best thing is to be at a more southerly location, so if you're in the northern hemisphere and travel south in the winter, take your binoculars!
[quote="Visual_Astronomer"]Omega Centauri is one of the most spectacular objects in the sky for the visual astronomer. Make an effort to view it, even if all you have are binoculars. It is worth the effort![/quote]
I agree with you entirely, except not everyone is geographically located in a favorable position to do so. Omega Centauri has a declination of 47.5° south, so it's position is more favorable to observers in the southern hemisphere. At a latitude of 40 degrees north, which cuts across the middle of the United States, Omega culminates just several degrees above the southern horizon (including a little boost from atmospheric refraction). Therefore, it's difficult to see, let alone see well, because of considerable atmospheric absorption down that low (even on nights with nice clear skies overhead, it's often murky near the horizon). As a result, it's a challenge just to spot Omega from 40°N, although I've heard of observers seeing it from Long Island, NY, and the north shore of Lake Ontario.
I've seen Omega a number of times from East Point, NJ ([url=http://apod.nasa.gov/apod/ap120108.html]the site of the APOD for January 8, 2012[/url]), on the north shore of the Delaware Bay (at 39.2°N latitude). When sky conditions permit, it's visible in binoculars, but typically, it's not really outstanding. On one lucky occasion (January 31, 2008), when transparency was unusually good over the bay, Omega was spectacular in my 16x70 binoculars, better than globular clusters M4 and M13 at the same time, which were at much higher altitudes. I've been trying to spot Omega for a while now from Coyle Field, an observing site closer to central NJ (at 39.8°N), but so far, I haven't had a definitive sighting yet.
Of course, the best thing is to be at a more southerly location, so if you're in the northern hemisphere and travel south in the winter, take your binoculars!