Howard B
January 21st, 2018, 07:34 PM
Asymmetrical spiral galaxy (Arp 25) and elliptical galaxy (Arp 114)
Cepheus
RA 07h 27m 17s
DEC +85d 45m 20s
Magnitude 11.8 (V) and 12.1 (B)
Size: 2.8 x 2.6 and 2.0 x 2.0 arc minutes
(magnitude and size data for NGC 2276 are listed first)
2866
These are two of the most economical Arp galaxies because NGC 2276 (Arp 25) and NGC 2300 (Arp 114) have only five minutes of declination between them so you can see two Arps in one interacting pair of galaxies. All but six other Arp galaxies this close share the same Arp number.
This is a nice bonus, especially if you’re out to observe all the Arp’s, but these two galaxies have an appeal beyond their designations. The slightly oval core of NGC 2300 is brighter and more obvious than the lower surface brightness of NGC 2276’s asymmetrical spiral arms. However, 2276 looks larger than 2300 and has some intriguing details.
Both galaxies are approximately 115 million light years distant, making 2276 about 90,000 light years in diameter. That’s only a little smaller than our Milky Way galaxy, giving a perspective on what our home galaxy might look like from that immense distance.
The asymmetry is a notable feature of 2276, and I was able to detect it with my 28-inch scope, with the small, faint core being noticeably off-center, with the brightest areas between the core and the near edge. I was able to see a linear feature that corresponds to an interior spiral arm, along with the faint arm that’s swings out from the general body of the galaxy. Halton Arp described it as “Tubular arm, straight at first, then bent. Secondary arm from straight portion.”
Unfortunately, I can’t find his comments about 2300.
However, my comments from a 2009 observation with my 28-inch scope read:
“Hey now, this is a dandy Arp galaxy! (this was before I realized each galaxy has its own Arp designation) The face on spiral is NGC 2276 and although a subtle sight it is definitely an asymmetrical face on spiral galaxy. NGC 2300 is the elliptical galaxy at the top (of my sketch) and is brighter than 2276, but the spiral is much more interesting because of its delicate spiral structure. Very nice! 253x, 21.13 SQM.”
By the way, north is on the right side of my sketch and the color DSS image from Wikisky.
2867 2868
Another indication that 2276 is the more visually interesting galaxy strikes me right now – look at all the field stars I included in my sketch around 2276, with none around 2300!
"GIVE IT A GO AND LET US KNOW"
Cepheus
RA 07h 27m 17s
DEC +85d 45m 20s
Magnitude 11.8 (V) and 12.1 (B)
Size: 2.8 x 2.6 and 2.0 x 2.0 arc minutes
(magnitude and size data for NGC 2276 are listed first)
2866
These are two of the most economical Arp galaxies because NGC 2276 (Arp 25) and NGC 2300 (Arp 114) have only five minutes of declination between them so you can see two Arps in one interacting pair of galaxies. All but six other Arp galaxies this close share the same Arp number.
This is a nice bonus, especially if you’re out to observe all the Arp’s, but these two galaxies have an appeal beyond their designations. The slightly oval core of NGC 2300 is brighter and more obvious than the lower surface brightness of NGC 2276’s asymmetrical spiral arms. However, 2276 looks larger than 2300 and has some intriguing details.
Both galaxies are approximately 115 million light years distant, making 2276 about 90,000 light years in diameter. That’s only a little smaller than our Milky Way galaxy, giving a perspective on what our home galaxy might look like from that immense distance.
The asymmetry is a notable feature of 2276, and I was able to detect it with my 28-inch scope, with the small, faint core being noticeably off-center, with the brightest areas between the core and the near edge. I was able to see a linear feature that corresponds to an interior spiral arm, along with the faint arm that’s swings out from the general body of the galaxy. Halton Arp described it as “Tubular arm, straight at first, then bent. Secondary arm from straight portion.”
Unfortunately, I can’t find his comments about 2300.
However, my comments from a 2009 observation with my 28-inch scope read:
“Hey now, this is a dandy Arp galaxy! (this was before I realized each galaxy has its own Arp designation) The face on spiral is NGC 2276 and although a subtle sight it is definitely an asymmetrical face on spiral galaxy. NGC 2300 is the elliptical galaxy at the top (of my sketch) and is brighter than 2276, but the spiral is much more interesting because of its delicate spiral structure. Very nice! 253x, 21.13 SQM.”
By the way, north is on the right side of my sketch and the color DSS image from Wikisky.
2867 2868
Another indication that 2276 is the more visually interesting galaxy strikes me right now – look at all the field stars I included in my sketch around 2276, with none around 2300!
"GIVE IT A GO AND LET US KNOW"