TVS Club Observatory and Dark Observing Site
The club leases a comparatively dark-sky observing site on a hilltop in the Diablo Mountains south of Livermore and east of San Jose. The name of the site is "Hidden Hill Observatory". The reason for that name is that the site is not open to the public and we do not want its location publicized. Also because it has a cool abbreviation: H2O.The site is well located for long-exposure astrophotography and deep-sky observing, especially in the southern part of the sky (we can see Omega Centauri in binoculars, well above the horizon but mostly obscured by lights). The site is at about 2400 feet in elevation and has an excellent low southern horizon looking over a large dark valley. It is not as dark as a remote location in the Sierra Nevada mountains, of course, but it is one of the darkest locations that is a convenient driving distance from the East San Francisco Bay Area. The site's location is not public, but we can tell you that it is approximately a 40 to 60 minute drive to the site from Livermore. The road is a mountain road: well paved, but narrow, windy, steep, unlit, one lane much of the way and there are no services available of any kind. Much of the road does not have any cell phone coverage. We do get a good signal from Verizon at the site, but not AT&T. There is no electricity or water at the site. The toilet facilities are primitive. There are no gas stations in the area. So if you go, be prepared.
This is private property, secured and restricted for authorized members and their guests at all times. Authorized (key holding) members can access the site any day of the year. Non-key holding members and the general public must be escorted to, while at, and from the site by key holding members -- NO EXCEPTIONS. To become an authorized member, visit our user agreement web page.
At least twice a year we try to hold an "open house" so that new and prospective members can visit the site. But the house is not really completely open. This is just a scheduled opportunity for a group to be escorted to the site and enjoy a night of observing.
A group of people at a recent H2O Open House. Photo by H. Jones.
The View to the South from the Observatory. Photo by G. Gottschalk.
The View to the North and East from the Observatory. Photo by G. Gottschalk.
Looking west we see three tiers of parking/observing sites
and a neighbor's [1] little observatory [2] on the hill [3] on the horizon.
They, being higher, have better seeing, but we have a darker sky.
[1] University of California, Santa Cruz
[2] Lick Observatory with the 120 inch Shane Telescope
[3] Mount Hamilton
Here is the Clear Sky Chart for our observing site:
H2O history
Jack and Pat started using the club's dark sky site soon after the club was formed. Records show that on 12/09/82 Jack signed a $100 lease agreement with the owners of the property where the site is located. Then a road was built and the south side of the hill was terraced so multiple observers could use the site without blocking each other's views. The site had been referred to by the name of the ranch for many years (a name which we no longer speak, to avoid unauthorized access). Under President David Anderson the board of directors named the building the "Sky Shack". After a vote by the Board in September 1998, the site was named "Hidden Hill Observatory". For many years in the 1990's and 2000's, star parties were held every month at the site.Jack, Pat and Roger Peterson built the original slide-off roof observatory in 1982-1983, and Jack built the observatory's Coulter 17.5" telescope and mount, which were operational in 1983. He donated the observatory to the club later. The scope was known as the Jack Marling Telescope and the building was known as "The Sky Shack".
The original Sky Shack Observatory. The roof slid off to the left. Photo by G. Gottschalk.
On August 31 2019, we finished a complete renovation of the observatory, including beefing up the foundation, replacing half the flooring, replacing the battery and solar charger, and redesigning the electrical system. We replaced the mount with a modern AP1200 mount that had been donated to the club by Nancy Finley with the help of the EAS. This effort was led by Gert Gottschalk and Chuck Grant. Unfortuntately most of this work was lost during a wildfire in 2010.
Herb Quick started building his fiberglass Home-Dome with Meade DS16 telescope in 1999 and donated it, unfinished, to the club in 2007 upon his death. In the early days a log book was kept to keep track of the site's usage. The dome remained unused until 2019, when Ross Gaunt undertook to restore it. He completed repairs to make it water-proof and rodent-proof, and added new floor and carpeting. He also installed a new electrical system with a battery and solar charger. We purchased a new Software Bisque mount and installed a Celestron C14 that had been donated to the club by the estate of John Westfall. The Paramount was made possible by a donation from Ross Gaunt. The Herb Quick Observatory is still on the site at H2O. The building and the telescope have not been formally named, but the dome has acquired the nickname "The Thunder Dome" due to the noise generated when it rotates.
The site also has four permanent piers which have bolt hole patterns suitable for mounting Schmidt-Cassegrains and other portable telescopes and lots of flat, hard ground suitable for Dobsonian and tripod mounted telescopes. There is room for parking 12-15 cars on top of the hill, with more parking below (our observing area is entirely on the top of the hill). As many as 10 cars can be parked in good observing locations with room to set up your telescope next to your car.
Ross and Dave with the Herb Quick observatory's equipment. Photo by H. Jones.
Jack Marling with his scope and club's new AstroPhysics mount. Photo by G. Gottschalk.
Patron members with Jack Marling at the dedication ceremony. Photo by G. Gottschalk.
Gert Gottschalk has also taken some nice photos at a recent open house.
H2O Reconstruction
In August of 2020, a large wildfire of nearly 400,000 acres burned through the area. It destroyed the slide-off roof observatory and the equipment inside. Fortunately the dome survived with almost no damage. You can see pictures of the damage done and reconstruction progress by clicking the picture:
Donations to TVS reconstruction
In the wake of the SCU Lightning Complex Wildfire that destroyed the H2O main observatory there was an outpouring of generosity to TVS from astronomy enthusiasts worldwide. We are pleased to announce a major donation to the TVS by David Friedberg, CEO of The Production Board, of a 20" PlaneWave Corrected Dall-Kirkham (CDK) Telescope, a Mathis MI-750 Fork mount, and a motorized 3.5 meter Observa-DOME! This donation was brokered by Prof. Alex Filippenko of UC Berkeley.See here for a list of donors.
