H2O (Hidden Hill Observatory)

TVS Club Observatory and Dark Observing Site

Here is the Clear Sky Chart for our observing site:
Clear Sky Chart

The club leases a comparatively dark-sky observing site on a hilltop in the Diablo Mountains south of Livermore and east of San Jose. 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). The site has a roll-off roof observatory that houses the club's 17.5-inch equatorially mounted Newtonian telescope. It has refigured Coulter optics, an aluminum tube, a modified Parallax Instruments mount, a Lumicon drive corrector, a two inch Crayford type focuser, a 12 volt storage battery system with solar powered charger, and various other accessories. We also have a Lumicon NGC Sky Vector computer system, but it is not currently installed. This telescope and many of the accessories were donated to the club by member, Dr. Jack Marling, who is also the founder of Lumicon.

The site also has four permanent piers which have bolt hole patterns suitable for mounting Schmidt-Cassegrains and other portable telescopes. There is also a dome that was originally donated to the club by Herb Quick. It is currently not usable, but if someone wants to get it working again, we foresee that it could be made available to anyone without requiring patron membership.

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). 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: narrow, windy, steep, unlit, one lane much of the way and there are no services available of any kind. Most of the road does not have any cell phone coverage. 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 to be escorted to the site.

Group of people
A group of people at a recent H2O Open House. Photo by H. Jones.

H2O south
The View to the South from the Observatory. Photo by G. Gottschalk.

H2O north and east
The View to the North and East from the Observatory. Photo by G. Gottschalk.

The Observatory. The roof slides off to the left. Photo by G. Gottschalk.

The 17.5-inch Telescope and the Observatory Director

Observing sites
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

Gert Gottschalk took some nice photos at a recent open house.