Invisible light travelling from the various parts of the universe reaches the Earth as infrared radiation. Its wavelengths measure 10 to 600 times longer than visible light. Infrared telescopes provide astronomers the opportunity to observe infrared light which provides valuable scientific information about stars and planets. Without infrared telescopes, this valuable data would be unknown.
Viewing Infrared Radiation
Infrared radiation, with its long wavelengths and lower frequencies, represent opportunities to study the origins of the universe. However, most infrared radiation striking Earth from outer space is absorbed by water vapour in the atmosphere. This absorption takes place mostly at altitudes below 41,000 feet. To avoid this obstacle to viewing infrared radiation, telescopes must either be mounted in aeroplanes that travel above this altitude or, in ideal circumstances, on satellites.
Infrared telescopes seek out and discover planets circling other star systems. One such telescope performing that task is the 10-foot telescope atop Mauna Kea, Hawaii. Despite being below the 41,000 foot threshold, this telescope on a mountain discovered an organic molecule in a plane the size of Jupiter located 63 light years from Earth, according to NASA's Jet Propulsion Laboratory. This discovery furthers the research on atmospheres of these so-called exoplanets. The ability to study the more than 400 exoplanets with land-based infrared telescopes allows for further and faster research without relying on orbiting telescopes.
Far Away Objects
Objects at great distances from Earth tend to emit light in the infrared spectrum. These objects represent early galaxies and stars in the universe. Telescopes like the European Space Agency's Herschel, launched on May 14, 2009 and orbiting above the Earth's atmosphere, provide documentation of those stars and galaxies. Two of the objectives of Herschel are to investigate the creation of stars and the formation of galaxies, as Herschel collects long wave radiation from some of the most distant objects in the universe.
The James Webb Space Telescope, or JWST, named for a prior NASA administrator, is currently under construction with a launch date of 2014. It represents the latest technology in infrared telescopes. The telescope will be in Earth orbit approximately one million miles above the surface. JWST will have the capability to see the earliest galaxies in the universe and look through dusty clouds to see stars and planetary systems.
- Universe Today; What Is Infrared; Jerry Coffey, February 12, 2010
- NASA Jet Propulsion Laboratory: A Little Telescope Goes a Long Way
- Institute for Astronomy, University of Hawaii; Why Use an Infrared Telescope?; Alan Tokunaga; Fall 2003
- NASA: The James Webb Space Telescope
- European Space Agency: Herschel