The Discovery Center at Ridgefield, in conjunction with the New Pond Farm Observatory, 101 Marchant Road, West Redding, is hosting an astronomy program that is open to the public on Saturday, April 29, starting at 8:30 p.m. In celebration of International Astronomy Day, participants will gaze through telescopes at the mountains, mare and craters of the crescent moon and have an opportunity to take a photo if they have a smartphone. Astronomers will also share views of Jupiter, which has entered the early evening sky with its moons and atmospheric bands. The winter and early spring constellations will be pointed out and discussed. Before the program, at 8 p.m. in the classroom building, there will be a review of sky objects to be viewed for those wishing to attend. Bring a flashlight for the walk from the parking area to the observatory and binoculars, if you have them. The program is $4 per person for Discovery Center members, with a maximum of $16 per family. For nonmembers, the charge is $6 per person, with a maximum of $24 per family. Registration is required. Visit the Discovery Center website to register, ridgefielddiscovery.org\/, or call 203-438-1063. If it looks as if the skies might be cloudy, check the website after 4 p.m. for program status.