Key To Terms

These are some of the telescopes that have been used to produce images of objects at different wavelengths. See also our Understanding the Images section, which serves as a quick guide to the images and terms in the Photo Album.

VLA:

The VLA , or Very Large Array is an observatory that looks at astronomical objects in radio wavelengths. It is located in Soccoro, New Mexico, and consists of 27 antennas arranged in a huge y shaped pattern. Each antennae is mounted on a movable track and at the maximum separation, the Array is about 36 km (22 miles) across! The VLA observes at different radio bands between 300 and 50,000 MHz.

The Hubble Space Telescope:

Hubble is a space-based observatory developed by NASA and the European Space Agency. Hubble "sees" objects in the Visible and Ultraviolet region of the spectrum. Since it is in orbit, its view is not obstructed by the Earth's atmosphere, which tends to distort our view of astronomical objects. Hubble was launched in 1990 and is expected to remain operational for 15 years.

The Digitized Sky Survey (DSS):

The DSS is a digital library of visible light images. These images are produced from photographic plates of the sky made by the Mount Palomar Observatory in California and the UK Schmidt Telescope in Australia.

MDM:

The Michigan-Dartmouth-MIT Observatory is located near Tucson, Arizona, on the southwest ridge of Kitt Peak. The Observatory operates 1.3 m and 2.4 m optical telescopes, equipped with a wide variety of detectors.

IRAS:

In 1983, the Infrared Astronomical Satellite performed an all-sky survey in 4 different wavelengths of the Infrared region of the spectrum. The IRAS images you see in the Photo Album were taken in wavelengths of 12 and 60 micrometers. IRAS was a joint US, Dutch and British satellite.

ISO:

The Infrared Space Observatory is an astronomical satellite that was operational between November 1995 and May 1998 observing in infrared wavelengths from 2.5 to 240 micrometers. ISO was an ESA (European Space Agency) mission with the participation of ISAS (Japan) and NASA (USA).

ROSAT:

ROSAT, or the Roentgensatellite, was named after Wilhelm Roentgen, the discoverer of X-rays. ROSAT is an X-ray observatory that was developed by Germany, the United States and the United Kingdom. Since X-rays cannot penetrate the Earth's atmosphere, ROSAT, like previous X-ray observatories, was launched into orbit around the Earth. Throughout the course of its operation ROSAT produced a survey of the entire visible sky and also identified many new X-ray sources.