Join the Denver Astrological society for one of their monthly open houses at the historic Chamberlin Observatory. During the event, 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 reduced $1 per-person entry fee to the observatory. In addition to touring the observatory, the monthly open houses are a great time to interact with members of the DAS and get answers to questions about your telescope (feel free to bring your scope to set up outside of the Observatory as many DAS members do) or anything you see in the sky! Chamberlin Observatory Open House info.