OR: Galaxies both near and far.
by Steve Gottlieb
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On Thursday night, December 1, I met with friends Dennis Beckley and Carter Scholz at Lake Sonoma, our “close-by” observing spot in the rural Sonoma County vineyards, about an hour and half drive from my house in the San Francisco east bay area. Carter was eager to have first light with his new 16-inch Zambuto mirror and Dennis had to check out his new Greg Blandin Cross Bow Platform on his 18-inch Obsession. Observing this time of year often comes with some compromise in terms of conditions. We were fortunate to have clear skies, pretty good transparency, dry conditions (relatively low humidity) and no wind. But seeing was subpar due to the jet stream and that restricted high power viewing. Our first target for the night was the insane outburst of Blazar CTA 102, a quasar with a redshift of 1.037, implying a light-travel time of nearly 8 billion years. This quasar has a normal quiescent brightness of 17th magnitude but it is known to go into outburst — so it is classified as an Optically Violent Variable (OVV) quasar. It’s in the midst of a historically bright outburst — as super-heated material spiral into the accretion disc surrounding the black hole, an intense magnetic field produces high-energy, relativistic plasma jets. That jet happens to be pointed directly at us, so we are looking down the throat of the jet! CTA 102 appeared marginally brighter than a mag 12.9 star on the AAVSO chart, so perhaps magnitude 12.7 or 12.8. To see an object so relatively bright, whose light has been traveling some 8 billion years to reach us, is humbling. A galaxy, — Steve Gottlieb |
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Abell Galaxy Cluster (AGC) 2626 The 5 brightest members in the central region of
Using 375x (about the highest power the seeing would allow), the brighter distorted spiral in Arp 70 appeared fairly faint, elongated 5:3 NW-SE, ~30"x18", broad concentration to
center, no distinct nucleus. It forms a close pair with Although Arp classified this system as a "Spiral with a small high surface brightness companion on arm", the stretched (tidal) northern arm of
Arp 128 is a close pair of overlapping and probably interacting galaxies. Arp placed this pair in his classification group of "Elliptical and elliptical-like galaxies, close to and perturbing spirals.” At 260x they were merged into a very faint glow elongated ~WNW-ESE, ~25"x15”. At 375x the glow occasionally "resolved" into two clumps, either connected or within a common halo. The 15" eastern clump was brighter and the 10" western component was extremely faint. A 12" pair of mag 14/14.5 stars is 2.7' S and a mag 13.7 star is 2.4' NE.
Oh my, this galaxy is nearly lost in the glare of 5.7-magnitude 10 Arietis. The first challenge is to split the bright star. It’s a mag 5.8/7.9 pair at 1.2”. With a two magnitude difference in brightness it’s a bit tough. But I split it at 280x using an 8" mask on my scope. The galaxy, though, required full aperture! Using 225x and 260x it was visible as a fairly faint, round glow, ~20" diameter. Although the surface brightness is surprisingly high, the view was improved with the glare of the star just outside the field, though the galaxy could still be easily seen with the bright star in the field.
WBL 102 = IC 329/330/331 triplet There’s nothing special individually about these three IC galaxies in southwestern Taurus, a region you wouldn’t normally go galaxy hunting. But check out the arrangement surrounding the 8th magnitude star! Quite unique and perhaps worthy of a nickname. The triplet was discovered French astronomer Stephane Javelle in 1891 while hunting for “nebulae” with the 30-inch refractor at the Nice Observatory.
Markarian 331 (part of the HIPASS J2351+20 triplet) HIPASS J2351+20 (radio survey designation) is an interacting triplet featuring Markarian (Mrk) 331. Mark 331 is a far infrared (FIR) luminous galaxy with an H II-like optical spectrum. NED classifies it as a LIRG — that’s a Luminous Infrared Galaxy. A LIRG emits one hundred billion times more far-infrared light than our sun does across the entire spectrum. Apparently the huge infrared emission is from starburst activity, perhaps from the interaction.
This photogenic spiral in Cetus was discovered by William Herschel in 1785 with his workhorse 18.7” speculum reflector. His notes read "pB, L, lE, lbM”, which translates to “pretty bright, large, little elongated, little brighter in the middle.” The Carnegie Atlas of Galaxies describes the photographic appearance as follows: "The beautifully symmetrical grand design in the pattern of NGC 151 contains a smooth central bar which terminates at the place where two inner arms begin. The arms do not spring from the ends of the bar but start from two symmetrically placed points about 15° downstream from the termination of the bar - a common-enough feature...The two principal arms that start at these places relative to the bar, fragment as they move outward and form the multiple-arm pattern in which at least four arm segments can be traced on each side of the galaxy.” Distance measurements place this galaxy at 150 million l.y. Through my 24”, NGC 151 appeared bright, fairly large, with a very bright boxy rectangular central section that is slightly elongated NNW-SSE (this is the central bar and nucleus), encased by a fairly low surface brightness halo extended at least 2:1 E-W, ~2.7'x1.2'. A mag 12.5 star is at or just off the ENE edge (1.7' from center). A superimposed companion (with the 2MASX designation) is at the tip of the eastern spiral arm of the galaxy, very close southwest of the mag 12.5 star. It was marginally glimpsed but occasionally popped.
NGC 722 lies a mere 7' SSE from the glare of 2.7-magnitude Beta Aries! This is a very similar situation as It was picked up immediately, though, as a fairly faint glow, elongated 3:2 NW-SE, ~30"x20", with a slightly brighter nucleus. A group of mag 11.5-13 stars is nearby, including a mag 12 star 2.7' ENE.
This one was fairly challenging as it doesn’t have a brighter core and the surface brightness is low. But even worse is the 12th magnitude star just off the west side, which severely hinders the view. Using 260x it was seen as an extremely faint, thin edge-on 5:1 WNW-ESE, ~40"x8”. Switching to 375x, I noticed a16th mag star superimposed on the WNW end.
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