An evening of visual astronomy at Lake Sonoma (I)

Drove up with a friend to Lone Rock Parking lot near lake Sonoma: a Bortle 3 site, 85 miles / 1h30 north of San Francisco for an evening of visual astronomy. I brought my 2.1x42 and 12x70 binoculars and my 10'' dobsnonian. My friend brought his 6'' newtonian.

Lone Rock is a very large gravel parking lot with a porta potty and no access gate. Part of the road is visible from the lot, so you have to cover your eye when a car drives down the road. 

We arrived a little bit after 8pm or thirty minutes before Sunset. There were just a couple of astronomers there. We chatted a bit but did not setup our gear next to them. As a result we never looked through their scopes. One of them had a 18'' f/4 motorized dobsonian. It surely would have been quite a sight. A large (and loud) group came after dark and left about an hour later.

My friend forgot an adapter ring for his focuser so was initially unable to achieve focus with any of his eyepieces. After borrowing a ring from one of the astronomer, he figured he could use the 1.25'' adapter from the Barlow to achieve the necessary distance. As a result he stayed on the Baader Hyperion Zoom the whole time (a fantastic eyepiece by the way).

As the sky got darker, more and more stars became visible and we could see the two bands of the milky way. To the south east, you could see the light dome of civilization close to the horizon. The abundance of stars made initial aiming of the telescopes kind of hard (without a laser). Constellations became even confusing to recognize with so many bright stars!

We started with the moon and planets, saw many DSOs and wrapped up with more planets around 1:30 am as some clouds started showing up near the horizon. The temperature remained pleasant and the wind light throughout. It was a fantastic evening of observations.

Observations:

  • Moon: beautiful as a 7% crescent 
  • Venus (about 10 degrees up from the horizon) - with zoom and Barlow, it was a blurry disk with one side a bit dark blue
  • Mars - did not use a lot of magnification - so it was just a dot
  • M44 (Beehive Cluster) - Cancer - through the telescope and both pair of binoculars (it got visible through the 2.1x42 once the sky darkened a bit)
  • M4 (Crab Globular Cluster) - Scorpio
  • M104 (Sombrero Galaxy) - Virgo - recognizable shape
  • Mel 111 (Coma Star Cluster) - visible with the naked eyes
  • M65, M66, NGC 3628 (Leo Triplet Galaxies) - Leo - hamburger galaxy was faint but its rectangular shape was recognizable
  • M95, M96, M105 (Galaxies) - Leo - at least two of the three - just blobs
  • M51 (Whirlpool Galaxy) - Canes Venatici - could see a bit of the arms
  • M101 (Pinwheel Galaxy) - Ursa Major - faint but visible nonetheless
  • M81 (Bode's Galaxy), M82 (Cigar galaxy) - Ursa Major - a lot brighter that in the city but no real details beyond the vague outline
  • M94 (Croc's Eye Galaxy) - Canes Venatici - a round blob
  • M108 (Surfboard Galaxy) - Ursa Major - somewhat faint
  • M97 (Owl Nebula) - Ursa Major - tried the OIII filter but it did not see to make the difference - could not see the "eyes" - but the disk itself was easy to see
  • M57 (Ring Nebula) - Lyra - could make out the ring (no colors of course)
  • Failed to see C27 (Crescent Nebula) - did not try the filter
  • M56 (Globular Cluster) - Lyra
  • Albireo (Double Star) - Cygnus
  • M27 (Dumbbell Nebula) - Vulpecula - nice
  • Failed to find M71 (because rushing) - but my friend saw it
  • Wanted to finish with a bright cluster (M13), but had trouble finding Hercules with so many bright stars near the zenith, so went for M5 (Rose Globular Cluster) - Serpens instead. A great sight.
  • Before packing up, noticed Jupiter/Saturn near the ESE horizon. First got a look with 12x70. I could see the four moons of Jupiter and a slightly oblong shape of Saturn. Then I pointed the telescope (I had to drag it for Jupiter since the car was in the way). I was able to see a dark belt on Jupiter. For Saturn, I could clearly separate the disk from the rings. A great way to wrap up the night!