Star Parties

The SAS organizes monthly star parties at Green Lake and Paramount Park which are free and open to the public. People of all ages and background, including children, are welcome. These events offer to all the opportunity for telescopic viewing of sky objects as well as educational interaction of experienced, knowledgeable astronomers with each other and with participants who may have limited or minimal understanding of astronomy. A typical star party gathering features observing through at least two or more different types of telescopes provided by SAS members along with the opportunity to ask questions, to discuss the observation process, and to learn about many astronomical topics: solar system objects, deep space objects, constellations, types of telescopes, and any other topic of interest.

These star parties are scheduled each month for the Saturday evening closest to the first quarter moon, but the time for beginning each star party varies due to seasonal changes in sunset times. Also, if weather turns out to be unfavorable for observing, a cancellation notice for the affected star party will be posted here on the SAS site home page and in the Through the Clouds SAS forum at least two hours before the scheduled time for the event. Anyone planning to attend a star party should always check these sites for possible notice of cancellation before traveling to a star party site. And even if the weather seems ideal, bringing a warm coat and possibly a warm drink is always a good idea.

The SAS also schedules star parties that are open only to SAS members. But SAS welcomes to the public star parties all who are curious about astronomy and interested in sharing the excitement and reward of astronomical discovery!

Come and share the
excitement & reward of
astronomical discovery

Star Party Dates & Times

Please see maps and directions for more information on the exact location of these star parties and how to get to them.

Please follow us on Twitter at @SeattleAstroSoc to get up-to-minute information of the star parties.


There are currently no more star parties open to the public scheduled for the next 6 months.


Outreach star parties are hosted by SAS, and are specifically geared toward introducing the general public to astronomy.

There are currently no more star parties aimed at outreach for the next 6 months.


SAS-members-only star parties, currently held at Rattlesnake Mountain Trailhead, are not open to the public.

These star parties are scheduled to take place east of Seattle on the one Saturday of each month which is during or closest to the time of the new moon. SAS members may plan attendance at these star parties by checking the calendar or list of events below for the Rattlesnake Mountain Trailhead Star Party dates and times.

There are currently no more SAS-members-only star parties scheduled in the next 6 months.

SAS Guidelines for Members-Only Star Parties

The Seattle Astronomical Society (SAS) has established the following set of guidelines to be followed at all SAS star parties. These are common sense in nature and are intended to maximize everyone’s enjoyment while attending an SAS star party. If you have any questions regarding these guidelines, make certain you understand these guidelines by asking the key master of the event for answers to those questions before arriving at the star party . The key master has final authority during a star party, so please abide by his or her direction.

Some of the listed items below concern lighting during a star party. Proper dark adaptation of the human eye for visual astronomy requires approximately 30 minutes to achieve, and a bright light of any color is known to disrupt dark adaptation and spoil an observer's night vision. Moreover, astronomers who are imaging with sensitive cameras suffer ruined images with bright light intrusion. For the benefit of all, please prepare in advance so that your lights will not disturb others.

  • Be certain you are familiar with the observing site. If you are not familiar with the area, plan to arrive extremely early so that you are not late. Knowing where you are going and arriving on time can ensure that you will avoid disrupting everyone with your headlights or being locked outside the observing area.
  • You are responsible for your guests and children. If you bring a guest or a child, please share these guidelines with them; and make certain that these guidelines are well understood and followed faithfully by all attendees.
  • No open fires are permitted. Use a camp stove for cooking. If you are using a propane or white gas heater in your tent or camper, be certain that you have adequate ventilation.
  • No littering should occur. If no trash containers are provided, carry your garbage out when you leave.
  • No white lights should be used after dark. Use only dim, red lights after sundown, and restrict all light use to the minimum light necessary for safety. Make certain all auto door lights, trunk lights, and backup lights are heavily shielded. (Pull fuses or unscrew bulbs if necessary.) No white lights should be used after dark.
  • Members-only star party starting and ending times shall be clearly identified on the SAS website, shall be rigidly observed by all SAS members, and shall be enforced by the key master. For members-only star parties no automobile entry or exit from the parking lot will be permitted during the star party unless all personal and vehicle white lights have been extinguished or shielded from the view of all other star party attendees. Please do not ask to be the exception to this guideline.
  • No green laser pointers or bright, red lights are permitted at members-only star parties unless they are authorized by the key master. If you bring a red light that, in the opinion of the key master, is excessively bright, the key master is fully authorized to ask you to further shield or extinguish it. The fact that the light is red does not mean it will not impact the night vision of some star party participants.
  • Always park in a way that will facilitate leaving with an absolute minimum of light display to other observers. Park so that your car is facing towards the exit to avoid unwelcome illumination from backup lights. Shift quickly and smoothly past the reverse gear and into drive mode. If you are planning to leave early, park close to the exit and as far from other members and their telescopes as possible. Before you turn on any personal or vehicle lights, alert the key master. When you are given authorization to leave, call out loudly to all other star party attendees that you are planning to leave; and give at least ten seconds notice. Then leave as directly and quickly as you can safely manage your exit. If you do not bring a telescope, park at least 100 yards from all telescopes; and walk into the area. Remember and remind your guests that no white lights should be used after dark!
  • Take every precaution to drive safely while in the observing area. If dust is in any way a problem, drive very slowly. Keep dust at an absolute minimum.
  • Leave small children and pets at home. Generally, SAS public star parties are family-friendly events, and kids are welcome. However, with regard to members-only star parties, young people must be old enough to follow the requirements imposed by these guidelines. Pets can be a serious safety problem in darkness as they may present extra hazards, leading to tripping, in addition to the usual possibilities of tripping over tripods, batteries, cables, etc.
  • Keep noise to a minimum. Please, refrain from using loud radios or other electronic sound sources and from any unnecessary noise or yelling, etc. Keep cell phones on the lowest volume settings, and keep phone conversations brief. If you want to listen to personal music, please use headphones.
  • Cell phones, tablets, and laptops must be shielded. These devices are surprisingly bright and can disturb the night vision of the user as well as that of other observers nearby. Please turn screen brightness to the bare minimum, and engage red display mode if it's available. Those who plan to use their devices throughout the observing session should please use appropriate red filters (e.g., Rubylith).
  • Use parking lights only. Even at the end of the established star party time, when you are leaving the immediate vicinity of the observing site, exercise genuine respect for the night vision of any remaining observers. If you experience any trouble in seeing with just parking lights, then ask a friend with a red light to walk ahead of your vehicle until you are well beyond the observing area. No headlights should be used! Nothing destroys a person’s night vision, spoils an astrophoto, or ruins the camaraderie of a lovely star party experience like misdirected car headlights.
  • Never leave anyone alone at the observing site when the star party ends. Some SAS observing sites are in remote locations. Be sure no one is left behind due to car trouble or other unexpected issues.

Following these guidelines should allow every star party participant to have a fun, safe, and enjoyable star party experience. Remember that the key master is an observer, too, and that he or she deserves to enjoy some quiet observing time.