We have begun to understand the high energy processes occurring in outer space such as neutron stars, quasars and black holes. Ultraviolet radiation is another form of radiation used in exploring outer space. The wavelengths of Ultraviolet radiation range between 4000 angstrom units and 150 angstrom units. Natural ultraviolet radiation is produced mainly by the sun. However ultraviolet radiation can also be produced artificially by electric-arc lamps.
Ultraviolet radiation is very useful in astronomy.
Ultraviolet radiation detectors have been used since the early 1960's on artificial satellites. This has provided astronomers with data on stellar objects that can't be obtained from the surface of the earth. An example of such a satellite was the International Ultraviolet Explorer, which was launched in 1978. Infrared Radiation is the third type of radiation we researched on. The wavelengths of infrared radiation are shorter than those of radio waves and longer than those of light waves.