indome_01 The Sacramento Valley Astronomical Society maintains observatories in the Northern California Sierra mountains for use by its members and for research purposes. The site hosts star parties throughout the year (as many as three a month). In case of bad weather, the alternate site for our star parties is Prairie City.

Please see the Event Calendar page for member star party dates.

The SVAS has a “Special Use Permit” (view by clicking here) with the U.S. Forest Service (USFS) for use of an area within the boundaries of the Tahoe National Forest. The SVAS area, called the “permitted area” here, is adjacent to an airport. The airport property also has a “Special Use Permit” that has been issued to Placer County by the USFS. Placer County and the Federal Aviation Administration (FAA) govern use of the airport property and their rules apply to all members of the public who use the Placer County and FAA permitted areas.


Rules Governing SVAS’ SUP area

(approved April 15, 2011)

Henry Grieb Observatory (HGO) General Rules:

Use of the Permitted Area:

  1. Signing your SVAS membership application form each year signifies your understanding and agreement to abide by these rules. A copy of your membership application form will be kept on file with the SVAS Board. Only SVAS members in good-standing, and current with membership dues, are allowed to use the permitted area at any time.
  2. SVAS members may invite up to four guests in the permitted area. Members wanting to invite more than four guests must obtain advanced approval, in writing, from a SVAS Board Officer. Guests must agree to abide by these guidelines. SVAS members are responsible for their guests. SVAS Board Officers have the authority to ask members and non-members to leave the area.


  • Access to the observing area will be in accordance with the following priorities:
    • SVAS Members
    • Guests of SVAS Members
  • Guest vehicles will not be allowed on the tarmac without telescopes during events when space is limited. Parking is available in the cul-de-sac.
  • The gated entrance must be closed behind you when entering or leaving HGO.
  • Carry out all your trash. There are no public trash cans.
  • Park with a maximum of 3-4 feet between vehicles. Set up your telescope and seating area in front of or behind your vehicle, never to the side. The Observatory Director (only) may relax these restrictions if space permits. If parked against the “off limits” dirt overrun area between the tarmac and the runway then set up telescope on the tarmac side only. Emergency vehicle access lanes must be free from obstructions at all times!

Prohibited Areas and Electrical Power Restrictions


  • The runway
  • The dirt “aircraft overrun” strip between the runway and the parking tarmac
  • The property which houses the National Weather Station Structures near the main entrance.
  • The other observatories south of HGO
  • Parking at the south end of the tarmac is for airplane parking, CHP helicopter refueling, and the private observatories. Blue tarmac lines define the area.
  • Power outlets on HGO are for telescopes and accessories only. No coffee pots, heaters, camper hookups, etc. are allowed. There are only 30 amps of available power and SVAS does not have access to the main fuse box.

Safety Rules

  • Airplane traffic has priority at all times. You may be asked to move your observing site if additional aircraft parking room is required.
  • Bicycles, skateboards, rollerblades, roller-skates, frisbees, and pets are not allowed.
  • Children under age 16 must remain under positive parental/guardian control at all times.
  • Smoking, alcoholic beverages, and cooking (except the microwave) are not allowed inside HGO.
  • Use caution walking in the south area of HGO at night: the class area benches and piers are difficult to see in the dark.
  • Smoking is strongly discouraged due to damage to mirror coatings. Use an ashtray, not the ground.

White Light Discipline

  • All flashlights used after dark must be red filtered to protect astrophotography exposures and night vision of observers.
  • Use your car’s owner’s manual to find and remove the fuse for white dome lights, trunk lights, etc. Or cover your lights with tape and/or other coverings.
  • If you intend to leave during the night, park so you will not have to engage your white “backup” lights when you depart or cover your lights. Ask for someone to guide you to the gate with a red flashlight. Reinstall your fuse(s) or uncover your lights in the cul-de-sac.
  • NEVER yell at anyone who violates the “no white light” rules. Respectfully assist them as you can and explain the necessity of red lighting.


  • Camping is allowed on the SVAS permit property only. The area is defined by HGO, the tree line and the eastern edge of the tarmac. All other dirt areas are off limits due to aircraft overrun or private permit requirements. Camping in cars or on the ground of the tarmac is not allowed.
  • RV/5th wheel/pop-up campers are limited to SVAS MEMBERS ONLY. Guests with vehicle campers will be required to set up outside the airport property. Space is limited.
  • A maximum of six RV/5th wheel/pop-up campers will be allowed on the property on a first come basis and must remain all night. Camping vehicles must be parked on the northwest end of the tarmac as close together as possible. Back into the dirt as far as possible. There is no RV hookup or power available. Water or sewage dumping is not allowed.

Prairie City

In case of bad weather at Blue Canyon, our member star parties are sometimes held at the Prairie City Recreation Area, in Rancho Cordova, CA. Contact Kevin Heider before attending, there must be a Board Member present.

Directions to Prairie City

From Hwy. 50 Eastbound take the Prairie City Road exit.
Turn South to White Rock Road
Turn Right (West) to Prairie City Recreation Area

Prairie City State Vehicular Recreation Area
3300 White Rock Road
Rancho Cordova, CA