Looking for something different to visit on the next great American road trip? Ever wonder what really happens in those mountaintop observatories? Many of the great astronomical research facilities in the U.S. are an easy road trip from major cities. Many are still active research facilities, while others have transformed mostly to public outreach activities, as the encroaching light pollution of the same nearby cities has pushed astronomical research farther out into the wilderness or into the depths of space. Still others offer a unique view of the rich history of science and astronomical research in the U.S., which really took the lead in the field in the late 19th and early 20th centuries with a burst of telescope and observatory construction. Here are 10 interesting observatories open to visitors, listed in no particular order.
10. McDonald Observatory
Located in the Davis Mountains in remote western Texas, the McDonald Observatory started operations in 1933. Today, the site houses several world-class telescopes, including the 9.2-meter, segmented-mirror Hobby-Eberly Telescope, one of the world’s largest optical telescopes. You won’t get to look through the large scopes — astronomers themselves rarely look through telescopes anymore, and instead equip them with complex imaging packages — but the site hosts occasional nighttime viewing, the West Texas Star Party every May, and daily solar viewing.
9. National Solar Observatory
You can just pick out the white vacuum tower of the solar telescope on the ridge of the Sacramento Mountains from the desert floor below in the town of Alamogordo, N.M. A long, winding drive up through the mountains brings you to the aptly named tiny town of Sunspot and the National Solar Observatory. Part of the Global Oscillation Network Group (GONG) which monitors the Sun worldwide around the clock, the site is dedicated to solar physics. The most prominent instrument is the 136-foot-tall Richard B. Dunn Solar Telescope, which continues down another 193 feet underground.
8. Green Bank Observatory
First operational in 2000, the 100-meter Robert C. Byrd Telescope is the largest fully steerable radio telescope in the world. It’s hard to miss the large scaffolding of the dish rising out of the hilly West Virginia landscape as you drive down State Highway 92 near the town of Green Bank. It replaced a previous telescope erected at the site in 1962. Here’s a strange modern tale about Green Bank: folks who claim to have sensitivity to modern WiFi and other electromagnetic sources have moved to the area, as Green Bank is a “radio quiet” zone, and you’ll see “no cell phone” signs everywhere if you visit.
7. Kitt Peak National Observatory
Located a short drive from Tucson, Ariz., on the Tohono O’odham Reservation, Kitt houses a collection of large telescopes, including the 4-meter Mayall Telescope and the McMath-Pierce Solar Telescope. Don’t miss a chance to venture into the solar telescope if it’s open to the public: seeing the large projection disk of the Sun is unforgettable. Kitt Peak also hosts sky shows, daily tours, and an advanced observer program, for astrophotographers to stay overnight and use one of three large amateur telescopes to photograph the night sky. Nearly every mountaintop surrounding Tucson has a telescope on it, although Kitt Peak is by far the most accessible. And you can’t beat the price — the Kitt Peak visitor center is free, although there is a nominal fee for guided tours.
6. Very Large Array
Located near Socorro, N.M., the Very Large Array radio telescope observatory is known to many people for its appearance in the 1997 movie Contact. The 27 dishes in the array are all movable along various rail tracks, offering different configurations for the dishes to act as one large receiver. Not only is the landscape surrounding the dishes very photogenic, but you might just catch them moving the array from one target to the next, as the dishes move in unison like a field of giant metal sunflowers.
5. Yerkes Observatory
This observatory on the shores of Lake Geneva in southern Wisconsin became a crucial cornerstone in early American astronomy. The main dome houses the 40-inch refractor, installed in 1897 and still the largest operational refractor in the world. The complex was the brainchild of American astronomer and entrepreneur George Ellery Hale. It even features a hydraulic floor to move the observer up to the eyepiece. Public viewings are still given through the 40-inch telescope on occasion.
4. Griffith Observatory
Located within view of the iconic Hollywood sign, the Griffith Observatory offers a great blend of science and pop culture. Even if you’ve never been there, you might recognize it, as several movies and TV shows have been shot on the observatory grounds. Founded in 1935, Griffith Observatory is a mecca for public science outreach, promoting the scientific research farther afield in southern California at Palomar and Mount Wilson.
3. Lowell Observatory
Pluto’s still a planet in these parts. The famous telescope that Percival Lowell used to discover the dwarf planet is the highlight of this observatory just outside of Flagstaff, Ariz., Lowell founded the observatory in 1894, and his claims of spying Martian canals captivated the public imagination at the time. Lowell hosted a record 100,000 visitors in 2016. Although the “Pluto Telescope” closed in January 2017 for restoration, this observatory is still well worth a visit even during that procedure. The Clark Telescope built in 1895 recently underwent a two-year renovation.
2. Palomar Observatory
No list would be complete without mentioning the Palomar Observatory. Located 90 miles southeast of Los Angeles, Calif., Palomar houses the massive 200-inch Hale telescope. Hale saw first light in 1949, and stood as the largest telescope in the world until 1976. Palomar welcomes tens of thousands of visitors each year on guided tours of the facility.
1. Mauna Kea Observatory
With clear and dry dark skies located near the equator, the big island of Hawaii is ideal for modern astronomy. The Mauna Kea Observatory complex hosts several world-class telescopes, including the 8.2-meter Subaru telescope and the twin 10-meter Keck Observatory, the world’s largest optical and infrared telescopes. You’ll definitely feel the impact of the altitude and thin air on the drive up to the 13,796-foot summit, and there can be snow on the ground year-round. Mauna Kea is also a point of dispute between naturalists, native Hawaiians who consider the site sacred and astronomers, who may have to move the proposed Thirty Meter Telescope to the Canary Islands off the coast of Africa.