IR Spectrograph Captures Stellar Images

ITHACA, N.Y., Dec. 19 -- An instrument aboard NASA's recently launched orbiting infrared observatory has found evidence of organic molecules in an enormously powerful galaxy some 3.25 billion light years from Earth. Equal to 10 trillion times the luminosity of the sun, the galaxy is one of the brightest ever detected.

LIFTING THE COSMIC VEIL: Short-wavelength infrared view of spiral galaxy Messier 81. (Photo: NASA/JPL-Caltech/S. Willner, Harvard-Smithsonian Center for Astrophysics)

The instrument on the Spitzer Space Telescope (previously called the Space Infrared Telescope Facility, or SIRTF) is the infrared spectrograph, or IRS. Among the most spectacular details released were images taken with the space telescope's infrared-array camera and with its multiband-imaging photometer. The images include a glowing stellar nursery; a swirling, dusty galaxy; a disc of planet-forming debris; and organic material in the distant universe.

The IRS, one of three instruments carried by the space telescope, is the most sensitive infrared spectrograph ever to go into space. In less than 15 minutes, it produced a spectrum of the distant galaxy IRAS 00183, first observed by the infrared astronomical satellite in 1983. The spectrum "gives evidence for organic chemistry in a distant galaxy shortly after the formation of the Earth," said James Houck, professor of astronomy at Cornell University, who heads the scientific team on the $39 million IRS contract with the Jet Propulsion Laboratory, Pasadena, Calif., a division of the California Institute of Technology, which manages the mission for NASA.

"NASA's newest Great Observatory is open for business, and it is beginning to take its place at the forefront of science," said NASA's Associate Administrator for Space Science, Ed Weiler. "Like Hubble, Compton and Chandra, the new Spitzer Space Telescope will soon be making major discoveries, and, as these first images show, should excite the public with views of the cosmos like we've never had before."

Launched Aug. 25 from Cape Canaveral, Fla., the Spitzer Space Telescope is the fourth of NASA's Great Observatories, a program designed to paint a more comprehensive picture of the cosmos using different wavelengths of light. While the other Great Observatories have probed the universe with visible light (Hubble Space Telescope), gamma rays (Compton Gamma Ray Observatory) and x-rays (Chandra X-ray Observatory), the Spitzer Space Telescope observes the cosmos in the infrared. Spitzer's unprecedented sensitivity allows it to sense infrared radiation, or heat, from the most distant, cold and dust-obscured celestial objects.

For more information, visit: sirtf.caltech.edu