CalStar highlights

[Steve Gottlieb]

Here are some of my favorites from CalStar, observed over Wednesday-Saturday nights.  Despite the two short nights due to the high marine layer, I logged over 100 objects with my 24-inch f/3.7 Starstructure, including a number of galaxy groups.  Early on I took a look at the remarkable field that includes the globular cluster NGC 6723, south of the Teapot (Sagittarius).  Even at a southern declination of -36.6°, this 7th mag globular was well resolved.  To the southeast (over the Corona Australis border) is a group of three bright reflection nebula - NGC 6726, 6727 and 6729.  NGC 6729, which fans out from variable R CrA, is a variable reflection nebula and is similar to the better known Hubble’s Variable Nebula in Monoceros.  And further southeast is one of the best dark nebulae in the sky — Bernes 157.  Using my 13mm Ethos, there wasn’t a single star visible in the field — that covers a portion of the sky as large as the full moon and even further southeast the sky was eerily vacant.

In an earlier observing report, Dan Smiley mentioned observing NGC 6928 (from the Pinnacles).  This is the brightest member of a galaxy group in Delphinus - not your usual go to location for galaxies.  I took a look at the group on Wednesday night and logged all 5 members in this SDSS image in this group, as well as the tiny companion at the top edge of NGC 6930.  

Another excellent galaxy group surrounds NGC 6962 in Aquarius and includes a half-dozen NGCs.  The main galaxy shows beautifully symmetric arms (see the SDSS image below or Adam Block’s image) but these were too low surface brightness to see any structure.  I’ve observing this group a half-dozen times since 1984 (first with a 13.1” Coulter Odyssey I) and always find it a fun challenge.

Speaking of challenges, the two objects arrowed in this image (MAC 2-123 and MAC 2-203) are perhaps the two brightest (in the V band) member stars of M31.  Although I have observed a single known star in M33, I’ve never attempted ones in M31.  Using a line drawn between two nearby mag 12.3 and 13.1 stars, I was able to positively identify these mag 16.5 stars and showed them the Rick Linden and Alan Agrawal.  Rick followed up by tracking these down with his 32” (no problem).  These stars are A-type supergiants and confirmed members of M31, at a distance of 2.5 million l.y.!

I also tracked down three *very* distant galaxies that hit the 1 billion light year mark.  All were very small fuzzball, quite dim, with no special appeal — except their light had been speeding through space for the past 1 billion years! 

LEDA 97456 in Aquarius at 1.1 billion l.y.

PGC 71834 in Pisces at 1.1 billion l.y.

LEDA 188874 in Aquarius at 1.8 billion l.y.

Hickson Compact Groups are scattered across the Fall skies and I looked at HCG 86, 87, 88, 89, 93 and 97.

HCG 87 in Capricorn was captured in this fan favorite HST image.  A, B and C were seen, but not D.

HCG 88 consists of a quartet of spirals in Aquarius.  Three of these are relatively easy NGCs in a line — NGC 6978, 6977, 6976 — and one very tough galaxy, HCG 88D = PGC 65612.

Hickson 93 is a quintet of NGCs in Pegasus and includes the distorted spiral NGC 7549 — also known as Arp 99.  I caught just a hint of the spiral arms as brighter arcs on the outside of the central region, but nothing of the thin stretched extensions.  I’ve looked at HCG 93 a total of 7 times since 1989 and it’s one of the easier (relatively) quintets.

Finally, HCG 97 is another quintet — all with IC designations — and a range of magnitudes from 13.0 to 15.6.  Hickson 97 was discovered by one visual observer — E.E. Barnard.  He found it on 28 October 1889, while an astronomer at Lick Observatory.  While observing Brooks Comet (1889V) through the 36-inch Clark refractor, he stumbled across the entire quintet nearby!  I previously had seen the brightest 4 galaxies through my 18”, but this was my first successful sighting of HCG 97E.

[Jeff Gortatowsky]

I will STILL NEVER forgive you for giving Alan my bed. 

TOTALLY unfair!!!!

But a great report as usual. And shows while it was not super duper dark, it was worth being there!

Clear skies!

[Jamie Dillon]

The 6962 group. You raised a fun memory. On a good July night at the Peak in 2010, I mooched a view from Dave Goggin in the 30". Dunno if Dave is still around, he spent a lot of time that year swinging the 30" around.

It was some view of that group, 7 galaxies in one eyepiece field. Uranometria charts 6 of them.

4 nights later, back on the Peak, I went back that group with Felix my 11", did catch 4 of the group.