4.6 Astronomical Data & Collection Methods

Observing from Space

Our view of space from Earth is not perfect. Air and light pollution, cloudy weather, and distortion from heat and atmosphere are all factors that can obscure the view of space. To get a better view, astronomers position instruments outside the Earth's atmosphere.

Some devices that astronomers use in space are satellites and probes.

A satellite is anything that orbits around something else. There are natural satellites such as our Moon, and artificial satellites such as communications devices orbiting Earth right at this moment.

Probes are devices sent, with no human pilot, to another celestial body to gather information. Sending probes into space is usually less costly than sending humans, and less dangerous. However, there is some debate as to whether a machine can gather information as well as a human being. What do you think?

Over fifty years ago the Soviet Union launched the first artificial satellite to orbit the Earth. Since then, countries all over the world have launched satellites into space. Today there are over 9000 artificial satellites orbiting Earth, but only about one-third of these are actually functioning. That means there are over 6000 pieces of space junk orbiting the Earth.