Friday, June 7, 2002

Shingletown Observing 6/7 - 6/8

A group of TAC subscribers spent Friday and Saturday observing at Shingletown, east of Redding, on the western slopes of the southern Cascades. Ancient Mt. Tehama's remnants, including Lassen Peak, stood snow capped against the deep blue sky to our east. While viewing conditions were poor in terns of stability and wind, but transparency was excellent.

The strong winds we had are unusual in the area this time of year. Those conditions made the airport unusable, so we took out binoculars, both hand held and on a bino-mount, and observed many bright Messier objects from in the street out front of the George and Althea Temple's home, there on Star Trek Drive. Dean, Ken, Evan, Kevin and I were joined later by Jane and Jim. The sky was no less than spectacular. I could not get over the feeling that I was standing in the lot at Bumpass Hell on a good night. We took in M4, M5, M13, M92, M57, M3, M101, M81 & M82, M27, Comet IK, M10, M12, M11, NGC7000, M53, and I'm sure more. We had a great time just being out under a wonderful sky and seeing what we could do with binos.

The next night was also windy, and we decided to set up in Temple's side yard. There are tall trees all around, which is a drawback, but overhead the sky again amazed. The Milky Way was highly granular through Cygnus, and the star clouds in Scutum heading toward the spout of the Teapot were billowy white. Our group was joined by Bob, Mags, and two amateurs from the Redding area that are part of the new TAC-Shasta mailing list. It was a very good group.

At one point I did a star count in the Finnish triangle described by Alpha CrB--Gamma-Alpha Boo, and came up with 61 stars, four more than I've seen at Bumpass Hell. 61 stars put my limiting magnitude at 7.2. Since I count stars that I feel reasonably sure I see, but not but may not be 100% sure of (those that are at the limit of my perception) I usually throw out some. I discarded 10, and the limiting magnitude at 51 stars drops only to mag 7.0. Not a bad sky, and bodes very well for our Shingletown Star Party next month. By the way, the horizons at the airport are awesome!

Since we had limited horizons Dean and I picked one part of Draco and opened the Night Sky Observers Guide. We used 18" Dobs with powers ranging from 100X to 212X.

Copied from The Sky, we observed:

NGC 6742
Other description Planetary nebula disc.
Constellation Dra
Dreyer description Very faint, stellar.
Magnitude 15.0
RA 18h 59m 18.8s Dec: +48 28'02"
RA 18h 59m 18.0s Dec: +48 28'00" (Epoch 2000)
Azm 55 07'42" Alt: +40 14'07"
Size 0.5'

NGC 6690
Other description Very elongated galaxy.
Constellation Dra
Dreyer description Pretty faint, large, round, between 2 stars.
Magnitude 13.0
Surface Brightness 14
RA 18h 34m 43.0s Dec: +70 31'57"
RA 18h 34m 48.0s Dec: +70 32'00" (Epoch 2000)
Azm 25 25'20" Alt: +45 25'41"
Size 3.9' x 1.1'
Position Angle 170.0

NGC 6667
Other description Elongated galaxy.
Constellation Dra
Dreyer description Very faint, pretty large, little extended, very faint double star nearby.
Magnitude 12.0
Surface Brightness 13.5
RA 18h 30m 38.2s Dec: +67 58'56"
RA 18h 30m 42.0s Dec: +67 59'00" (Epoch 2000)
Azm 28 59'08" Alt: +46 06'11"
Size 1.9' x 0.7'
Position Angle 104.0

NGC 6654
Other description Round galaxy with bright core.
Constellation Dra
Dreyer description Star of magnitude 12 or 13 in pretty bright, pretty large nebulosity.
Magnitude 11.6
Surface Brightness 13.7
RA 18h 23m 59.3s Dec: +73 10'55"
RA 18h 24m 06.0s Dec: +73 11'00" (Epoch 2000)
Azm 21 28'54" Alt: +45 45'41" Always above horizon. Transit: 10:25
Size 2.8' x 0.6'
Position Angle 62.0

Galactic Longitude 94
Galactic Latitude +27.1
Angular Size 115
Mean Radial Velocity:
RA 18h 21m 48.8s Dec: +64 21'29"
RA 18h 21m 51.2s Dec: +64 21'35" (Epoch 2000)
Azm 34 07'27" Alt: +47 20'12"
Size 1.9'

All but the PK were easy. The PK required higher magnification (212x) and an Oxygen III filter to reveal a hint of the object and its central star.

The remainder of the night was spent on eye candy. Most notable were:

The Veil Nebula (NGC 6690, NGC 6992-95) - marvelously twisted strands of warm taffy looking very 3-dimensional. The OIII filter revealed detail that I only see when in a true dark sky. The view was sufficient to create a line at my telescope, even at this small backyard star party!

The Crescent Nebula (NGC 6888) - only time I've seen it better was at Bumpass Hell parking lot. Even on Saturday night the view was of a complete "egg" shape - empty inside other than the bright star at the and nebulosity trailing off it to where it joins the brighter western and northern sections of the "egg".

M27 (NGC 6853) with an OIII filter - the apple core was obvious, in fact very bright. The rest of the nebula showed well, filling in the "eaten" parts and extending away into a somewhat oval shape.

It was going on 3 a.m. and the wind was coming up, blasting us on occasion with clouds of dust.

We were tired but satisfied. It was fortunate that we had our scopes set up where we were staying for the night, as we'd also been enjoying some wonderful coffee with Bailey's and Kahlua, which also helped warm us against the wind chill. Thank you again "Two Dob" :-)

One other object of the trip was attending a meeting with the Shingletown Activities Council and to again visit the airport. I will post under another topic the additional information we obtained this trip about the Shingletown Star Party.