Refracting telescope focus, results in a non-inverted and upright image. Galileo’s best telescope magnified objects about 30 times. Because of flaws in its design, such as the shape of the lens and the narrow field of view, the images were blurry and distorted. Despite these flaws, the telescope was still good enough for Galileo to explore the sky. The Galilean telescope could view the phases of Venus, and was able to see craters on the Moon and four moons orbiting Jupiter. Parallel rays of light from a distant object (y) would be brought to a focus in the focal plane of the
Craters of the Moon National Monument and Preserve Clinton greatly expanded the Monument area. The National Park Service portions of the expanded Monument were designated as Craters of the Moon National Preserve in August 2002. It lies in parts of Blaine, Butte, Lincoln, Minidoka, and Power counties. The area is managed cooperatively by the National Park Service and the Bureau of Land Management (BLM). The Monument and Preserve encompass three major lava fields and about of sagebrush steppe grasslands to cover a total area of . The Monument alone covers . All three lava fields lie along the Great Rift of Idaho, with some of the best examples