IMILOA ASTRONOMY CENTER: 600 Imiloa Place, Hilo, Hawaii; www.imiloahawaii.org or 808-969-9700. Located on the Big Island about 1.5 miles west of downtown Hilo on the University of Hawaii-Hilo campus. Open 9 a.m.-4 p.m.,Tuesday-Sunday. Adults, $14.50; children 4-12, $7.50.
MAUNA KEA: www.ifa.hawaii.edu/mko/visiting.htm. You can drive to the Visitor Information Center at the Onizuka Center for International Astronomy on the Mauna Kea access road. The center has nightly stargazing programs. The Web site also links to listings of commercial tour operators who can take you farther up to the 14,000-foot summit to view the domes of the observatory, but many visitors suffer from altitude sickness, the road is steep and unpaved, and visitors are not permitted to look through the telescopes.