Click above to buy a $40 family membership to the Adler Planetarium ($95 value). Buy here for a $30 individual membership ($65 value).

As Earth places its bid for the 2020 Intergalactic Winter Olympics, today's Groupon invites you to rediscover what makes the universe so neat (hint: pretty much everything). For $30, you get a one-year individual membership (a $65 value) to the Adler Planetarium. You can also get a family membership for $40.

The Adler Planetarium has been making an argument for the existence of space since it opened its doors as America's first planetarium in 1930. Its majestic Sky Theater translates the enormity of the night sky into a more easily comprehended dome ceiling. Unlimited daytime tickets and discounted evening tickets are available to members. Future astronauts and doubting astro-nots will receive a mind-expanding crash course in constellations, atmospheric gases, dark matter, black holes, lunar expeditions, nebulae, supernovae, and the odd profligacy of space-battles that have been observed in a galaxy far, far away—for starters. But like the cosmos themselves, there's more. So much more.

This membership grants you unlimited admission to the planetarium and its many shows and exhibitions, including One World, One Sky: Big Bird's Adventure, the Robert Redford–narrated meteor-fest Cosmic Collisions, and the musically coordinated 3D Universe: A Symphony, which proves that the music of the earth can elevate even the music of the spheres. The family membership covers unlimited admission and theater tickets for two adults and up to six children under 18 years old, while the individual membership covers unlimited admission for you and one guest. Both memberships include the added benefits of a 15% discount at the Infinity Gift Shop, 10% off in Galileo's Cafe, VIP access to new exhibitions, two complimentary guest passes for general admission, discounts on guided tours, and more. See the full list of privileges here. If nothing else, the planetarium provides a place where your love for dehydrated ice cream can blossom without judgment or water.

Reviews

Frommer's recommends the Adler Planetarium, saying:

• The building may be historic (it was the first planetarium in the Western Hemisphere), but some of the attractions here will captivate the most jaded video-game addict. Your first stop should be the modern Sky Pavilion, where the don't-miss experience is the StarRider Theater. Settle down under the massive dome, and you'll take a half-hour interactive virtual-reality trip through the Milky Way and into deep space, featuring a computer-generated 3-D-graphics projection system and controls in the armrest of each seat. Six high-resolution video projectors form a seamless image above your head -- you'll feel as if you're literally floating in space. – Frommer's

Yelpers and Insider Pagers alike give the Adler Planetarium four stars, while Judy's Book reviewers give it 4.4. TripAdvisors give it a solid three owl eyes:

• When it comes to Chicago museums, the Planetarium is often forgotten or overlooked. However, it's a great place to spend a day during any season. – Neal H., Insider Pages
• The Planetarium is a fascinating place to visit. The exhibits, telescopes, and tours all-together make the Planetarium a worthwhile place to see. – Oscar Y., Judy's Book
• There are tons of hands-on displays, and not just for kids.... All the displays really get you involved and find a way to make sometimes dull topics interesting. – Jenny S., Insider Pages