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 some birds also alter their times of activity. Some animals, like ground squirrels and marmots, have one or more periods of estivation, a summer hibernation that allows them to avoid the hottest and driest periods. Several animals are unique to Craters of the Moon and the surrounding area. Subspecies of Great Basin pocket mouse, American pika, yellow-pine chipmunk, and yellow-bellied marmot are found nowhere else. Lava tube beetles and many other cave animals are found only in the lava tubes of eastern Idaho. In May 1980 wildlife researcher Brad Griffith of the University of Idaho started a three-year study to