This is really a continuation of the first part, covering some of the objects from the first two nights at Grandview campground in White Mountains east of the Sierras. Here's one of the Tufa formations at Mono Lake to the east of Yosemite.
Tufa.jpg
In 1986 it was announced that "Observations at 21 cm and optical observations of the S0/Sa galaxy UGC 12591 show that this galaxy possesses the largest rotational velocity of any disk system known so far. At 500 km/s, it exceeds by 30 percent the largest values previously measured." UGC 12591 in Pegasus is one of the heaviest known spirals with a mass of 600 million solar masses (see ESO news release). Another source claims a mass of 2 trillion solar masses.
I found this monster moderately bright, elongated 5:2 or 3:1 SW-NE, sharply concentrated with a very small bright nucleus. There is a sharp light cut-off along the south edge due to a dust lane and the halo is more rounded or bulges out on the north wide. The section of the galaxy south of the dust lane was not seen with certainty.
NGC 7714:7715 = Arp 284.jpg
NGC 7714 and NGC 7715 = Arp 284 = VV 51
23 36 14.1 +02 09 18
V = 12.5 and 14.2; Size 1.9’x1.4’ and 2.6'x0.5'; Surf Br = 13.4 and 14.3; PA = 4° and 73°
This interacting, distorted pair lies in Pisces. For a remarkable HST image of NGC 7714 see http://www.spacetele.../news/heic1503/. The public news release reads "NGC 7714 is a spiral galaxy at 100 million light-years from Earth — a relatively close neighbour in cosmic terms.”
The galaxy has witnessed some violent and dramatic events in its recent past. Tell-tale signs of this brutality can be seen in NGC 7714's strangely shaped arms, and in the smoky golden haze that stretches out from the galactic centre.
So what caused this disfigurement? The culprit is a smaller companion named NGC 7715, which lies just out of the frame of this image — but is visible in the wider-field DSS image. The two galaxies [Arp 284] drifted too close together between 100 and 200 million years ago, and began to drag at and disrupt one another’s structure and shape.
As a result, a ring and two long tails of stars have emerged from NGC 7714, creating a bridge between the two galaxies. This bridge acts as a pipeline, funnelling material from NGC 7715 towards its larger companion and feeding bursts of star formation. Most of the star-forming activity is concentrated at the bright galactic centre, although the whole galaxy is sparking new stars.
Astronomers characterise NGC 7714 as a typical Wolf-Rayet starburst galaxy. This is due to the stars within it; a large number of the new stars are of the Wolf-Rayet type — extremely hot and bright stars that begin their lives with dozens of times the mass of the Sun, but lose most of it very quickly via powerful winds."
Visually, NGC 7714 appeared bright, moderately large, irregular shape. Contains a very bright quasi-stellar nucleus and a close knot on the NW side. The halo is irregular in outline. NGC 7715 2' E. NGC 7715 was fairly faint, moderately large, very elongated 4:1 WSW-ENE. Contains a brighter core and low surface brightness extensions (arms) that increase in size with averted vision to ~1.4'x0.35'. On images the western arm or tidal bridge stretches to brighter NGC 7714 1.8' W, though there was no visual connection. Located 3' N of mag 5.7 16 Psc and the bright star compromises the view.
This large, barred spiral is in Pegasus. I found it bright, fairly large, dominated by a central bar extending at least 3:1 E-W, ~45"x15". A very low surface brightness arm is attached at the west end of the bar and extends to the south. The corresponding arm extending north on the east end was less obvious and only marginally glimpsed. The arms blend into a low surface brightness halo ~2' in diameter. A nice mag 9.8/12 double star is off the NW side 2' from center.
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