Current Moon Phase
US Naval Observatory






Outstanding Speaker!

DAS members prepare for an Open House at Chamberlin Observatory
Photo by John Flemming

re you trying to decide which of the many telescopes on the market is right for you? Are you wondering what's the difference between a "Dobsonian" telescope and a refractor? Or ... what the heck is a Schmidt-Cassegrain telescope, anyway? We have discovered that one of the best ways to get the answers to those questions is to look through and try out a number of different scopes.

Or ... are you a student who needs information for an assignment; a parent who has a child with an interest in astronomy; a teacher who wants to enrich her student's science classes; a person who wants to find out how to get started as an amateur astronomer .. or who just wants to spend an interesting evening exploring something new?

You're in luck! Almost every month, starting at dusk, on the Saturday nearest the first quarter moon, the DAS hosts an Open House at the University of Denver's Historic Chamberlin Observatory. Guests can view the heavens through the observatory's famous 20-inch aperture Alvan Clark-Saegmuller refractor by checking in at the desk on the main floor of the observatory and paying a $2 per-person fee or $5 per family. If the weather is cloudy and not suitable for viewing with the observatory's telescope, there is a $1 per-person entry fee to the observatory.

Please see: Observatory Safety Rules & Access Considerations |

A bonus on Open House nights is that many Denver Astronomical Society members set up their telescopes on the observatory grounds (Observatory Park) to share with anyone and everyone interested in taking a look at the wonders of the universe -- stars, planets, galaxies, nebulae, star clusters and more! (There is no charge for viewing through DAS member telescopes.)

Members are happy to answer any and all questions about astronomy and their telescopes so you can start to explore the heavens on your own or learn which type of scope might be right for you and your interests.

If you already have a telescope, but can't quite figure out how it works, not to worry: bring it to the Open House and someone will help you.

Dates and start times for this year's Open Houses are provided in the list on the right side of this page.

The start time for Open Houses varies as evening twilight changes with the seasons. In the Winter, plan to be there by 5:30 or 6:00pm.  In the Spring and Fall, 6:30 or 7:30pm is about right. In the Summer months, 8:00 or 9:00pm. If you arrive early, you can watch DAS members set up their telescopes and other equipment for the night's observing.

No reservations required!
January 11th
Using Your Christmas Telescope (7pm)
February 8th
March 8th
April 5th
National Astronomy Day
May 3rd
Jupiter, Mars, Saturn!
June 7th
July 19th
August 2nd
September 27th
Colorado Astronomy Day
October 18th
November 1st
Buying a Christmas Telescope (7pm)
December 27th
Using Your Christmas Telescope (7pm)

How to


The Denver Astronomical Society
DAS Home Page