While most rejected this model during his lifetime, his work was eventually studied by Copernicus and others, bringing about general acceptance of this heliocentric model. Copernicus showed that a heliocentric model provided a better explanation of the observations than the geocentric model. Galileo is thought to have been the first astronomer to build and use a telescope. These discoveries helped to confirm the heliocentric model. Discuss how the opacity of the Earth's atmosphere limits the use of ground-based telescopes, and explain how astronomers are able to minimize or avoid this problem.
Opacity refers to the extent to which radiation is blocked by the medium it is travelling through.
The Earth's atmosphere prevents most types of radiation from reaching the surface of the Earth. Methods of minimizing or avoiding these problems include placing telescopes at high altitude, in dry locations, on balloons, or on satellites. Opacity prevents light from passing through our atmosphere, while seeing is the blurring effect due primarily to turbulence in the atmosphere. On a clear night, Earth's atmosphere is completely transparent to optical light, but seeing is still present. Describe the steps that an astronomer could take in order to measure these two properties for a sample of stars in the night sky.