May 2, 2015, is Spring Astronomy Day, when hundreds of organizations worldwide host special family-oriented events to showcase the wonder and excitement of the night sky.

Grand Canyon Star Party 2013. National Park Service / Kristen M. Caldon
Grand Canyon Star Party 2013.
National Park Service / Kristen M Caldon

One day each spring and fall, astronomy clubs, planetariums, and other groups of sky lovers band together to share the wonders and excitement of astronomy with their communities. The theme of Astronomy Day is “Bringing Astronomy to the People,” and amateur astronomers and science fans the world over can hardly wait to share their excitement about the sky with the general public.

Doug Berger, then president of the Astronomical Association of Northern California, founded this annual event in 1973 as a way of drawing local attention to the science and the hobby through exhibits and activities at urban centers. Since then, the celebration has mushroomed in size and scope. Hundreds of astronomy clubs, observatories, museums, colleges, and planetariums worldwide now host special family-oriented Astronomy Day events and festivities, often with the assistance of the Astronomical League. Some organizations extend their activities over an entire week.


Astronomy Day has traditionally been celebrated between mid-April and mid-May, on the Saturday closest to the first-quarter Moon. In 2007, the Astronomical League began promoting an additional day in the autumn. In 2017, Spring Astronomy Day falls on May 2nd. Fall Astronomy Day will be on September 27th. However, local organizers often host events on other dates that better suit their needs, or to accommodate a special event like an eclipse, planetary alignment, or bright comet, so be sure and check their calendars.

Solar viewing at NEAF
Solar observing has become a regular fare at many Astronomy Day activities worldwide. Here attendees at Northeast Astronomy Forum & Telescope Show enjoy views of the Sun in hydrogen-alpha light.

Why Participate?

This event is a great way for your club to gain visibility in your community. Having the public look through telescopes and at your displays spreads interest in astronomy throughout the general public and might even attract new members to your club. It provides a platform for discussing light pollution — an issue that should concern everyone. Perhaps most important, Astronomy Day is great morale-booster for you and your fellow club members. It brings people together for a day of sharing their love of the sky with others.

If you don't belong to an astronomy club and want to find a local club or planetarium that might be hosting an Astronomy Day celebration, check out our directory of clubs, observatories, planetariums, and science museums from around the world.

More Information

To assist organizations and individuals in planning Astronomy Day programs, the Astronomical League and Sky & Telescope have prepared a free, fact-filled Astronomy Day Handbook. Written by David H. Levy and updated by Gary Tomlinson and others, the 77-page guide offers time-tested suggestions for conducting large and small endeavors. It also includes the rules and entry forms for the Astronomy Day Award, a prize co-sponsored by Sky & Telescope, the American Astronomical Society, and the Astronomical League, and given annually to the groups whose programs do the best job of "Bringing Astronomy to the People."

Grand Canyon National Park Star Party 2013. National Park Service / Michael Quinn
Grand Canyon National Park Star Party 2013.
National Park Service / Michael Quinn

The Astronomical League maintains the official Astronomy Day web page, which describes the event's background and where to find an Astronomy Day activity in your area. Additional listings can be found through the Night Sky Network.

Also available for printing and handing out is the Astronomical League's The ABCs of Stargazing sheet, which can help you explain the basics of our hobby to newcomers. And don't forget our ever-popular Good Outdoor Neighbor Lighting flyer, a clear, simple info sheet on light pollution and how anyone can minimize it.

Astronomy Day is deliberately planned for dark-sky viewing, but the easiest target for new converts to find is the Moon, so you might want to pick up a few Sky & Telescope Moon maps to help answer the questions you're sure to get about our nearest neighbor.


You must be logged in to post a comment.