The Fred Lawrence Whipple Observatory sits in the Santa Rita Mountains, with a visitor and science center explaining the astrophysics work done here. Exhibits cover the telescopes and the surrounding sky, and the mountain setting gives broad views across southern Arizona.
Guided tours to the MMT Observatory are usually seasonal and limited, so check ahead before making the drive. Even without a tour, the visitor center is a useful stop if you are exploring Madera Canyon or the Tubac area.