These are optical (visible light) telescopes.
The electromagnetic spectrum.
Visible light is just one type of electromagnetic radiation. Radio waves, infrared light, ultraviolet light, X-rays, and gamma rays are other kinds of electromagnetic radiation. Radio waves have the least energy, and gamma rays have the most.
Left: the Green Bank 100 meter radio telescope in Green Bank, West Virginia.
Second from left: the Stratospheric Observatory for Infrared Astronomy.
Next: The Far Ultraviolet Spectroscopic Explorer .
Right: the Compton Gamma Ray Observatory.
Astronomers have (or have had in the recent past) telescopes that operate in all of the major regimes of the electromagnetic spectrum.
Coming soon! A
much higher resolution X-ray picture
of this galaxy group from Chandra! Stayed tuned!
For more images from the Chandra telescope, see the
Chandra web page.
Last updated: 7/21/02
The Chandra X-Ray Telescope . This telescope was launched into space in July 1999. X-ray telescopes must be above the Earth's atmosphere, since the atmosphere absorbs X-rays.
The Sun, as seen at X-ray wavelengths. This image movie was obtained from the Yohkoh X-ray satellite.
A Chandra X-ray picture of the double star Sirius A (the fainter star) and Sirius B (the brighter star). Sirius B is a white dwarf star, which is very faint at optical wavelengths but very bright in the X-ray.
A Chandra X-ray image of the Cassiopeia A supernova remnant. This is very hot gas that was blasted into space about 300 years ago, when a star exploded. The bright point in the center may be a neutron star, the very dense core of the star left behind after the supernova explosion.
The neutron star in Vela supernova remnant, as seen by Chandra. The two arcs of X-ray emission seen in this picture are believed to be the near edges of two tilted rings of X-ray emission, caused by shock waves rushing away from the neutron star. The straight line in the middle is a jet of material shooting out of the poles of the neutron star.
A picture of the central region of our home galaxy, the Milky Way galaxy. The white source near the center of the image is Sagittarius A*, a disk of hot gas swirling into a black hole with a mass about two million times that of the Sun. The extended emission around Sagittarius A* originates from hot gas near the center of our galaxy, heated by supernovae explosions and perhaps strong winds from massive stars.
The Orion Nebula, as seen by Chandra. A cluster containing about a thousand young stars can be seen in this image.
The picture on the left is an optical image of the Hydra A cluster of galaxies. The picture on the right is the same part of the sky, as seen in the X-ray by Chandra. In the optical pictures, we are seeing the combined light of the billions of stars that make up the galaxies. In the X-ray picture, we are seeing very hot intracluster gas that fills the cluster.
An optical image of the NGC 4410 galaxy group, from the Southeastern Association for Research in Astronomy (SARA) 0.9m optical telescope on Kitt Peak in Arizona. The inner part of this group contains five galaxies, at least four of which appear to be connected by bridges. Two tails extend to the southeast and northwest of NGC 4410A+B. This group will be observed with the Chandra X-ray telescope in April 2002.
Here is an X-ray map of the NGC 4410 group from an earlier X-ray telescope, the ROSAT satellite (contours). This image is superposed on the SARA optical image (colors). Both NGC 4410A and NGC 4410D are active galaxies, with X-ray bright nuclei.
Coming soon! A much higher resolution X-ray picture of this galaxy group from Chandra! Stayed tuned!
For more images from the Chandra telescope, see the Chandra web page.
Last updated: 7/21/02