in the park. Reptiles include the Great Basin rattlesnake, short-horned lizard, side-blotched lizard, striped whipsnake, and amphibians include the tiger salamander. Also in the park are the black, lumpy, very slow-growing colonies of cryptobiotic soil, which are a mix of lichens, algae, fungi, and cyanobacteria. Together these organisms slow erosion, add nitrogen to soil, and help it to retain moisture. Activities Most park visitors sightsee using the scenic drive, which provides access to 13 viewpoints over the amphitheaters. Bryce Canyon has eight marked and maintained hiking trails that can be hiked in less than a day. The following list includes round trip time and trailhead for each in parentheses: Easy to moderate hikes Mossy Cave (one hour, State Route 12 northwest of Tropic) Rim Trail (5–6 hours, anywhere on rim) Bristlecone Loop (one hour, Rainbow Point), and Queens Garden (1–2 hours, Sunrise Point) Moderate hikes Navajo Loop (1–2 hours, Sunset Point) Tower Bridge (2–3 hours, north of Sunrise Point) Strenuous hikes Fairyland Loop (4–5 hours, Fairyland Point) Peekaboo Loop (3–4 hours, Bryce Point) Several of the above trails intersect, allowing hikers to combine routes for more challenging hikes. The park also has two trails designated for overnight hiking: the Riggs Spring Loop Trail and the Under-the-Rim Trail. Both require a backcountry camping permit. In total there are of trails in the park. More than of marked but ungroomed skiing trails are available off of Fairyland, Paria, and Rim trails in the park. of connecting groomed ski trails are in nearby Dixie National Forest and Ruby's Inn. The air in the area is so clear that on most days from Yovimpa and Rainbow points, Navajo Mountain and the Kaibab Plateau can be seen away in Arizona. On extremely clear days, the Black Mesas of eastern Arizona and western New Mexico can be seen some away. The park also has a 7.4 magnitude night sky, making it one of the darkest in North America. Stargazers can, therefore, see 7,500 stars with the naked eye, while in most places fewer than 2,000 can be seen due to light pollution, and in many large cities only a few dozen can be seen. Park rangers host public stargazing events and evening programs on astronomy, nocturnal animals, and night sky protection. The Bryce Canyon Astronomy Festival, typically held in June, attracts thousands of visitors. In honor of this astronomy festival, Asteroid 49272 was named after the