2MASS Twin Telescopes Bring the Stars to Earth

AMHERST, Mass. - Amateur stargazers and high-level astronomers alike are now able to view a half-million galaxies and 162 million stars on their home computers, thanks to a massive release of images from an infrared sky survey. University of Massachusetts astronomer Michael Skrutskie is lead investigator for the project, which is sponsored by NASA and the National Science Foundation.

"Any computer with a Web browser can be transformed into a desktop observatory," said Skrutskie. The 1.9 million images would fill 6,000 CD-ROMs, equivalent to 4,000 gigabytes or four terabytes of computer hard-disk space.

"The general public can see a menagerie of objects in infrared wavelengths that they couldn''t see in any other way," said project scientist Roc Cutri of the Infrared Processing and Analysis Center (IPAC) in Pasadena, Calif. IPAC is operated by NASA''s Jet Propulsion Laboratory and the California Institute of Technology (Caltech), both in Pasadena.

"The current release is based on a volume of data several hundred times larger than that contained in the human genome," said Skrutskie. "Astronomers will become cosmic geneticists, searching out patterns in these sky maps to decode the structure and origin of the Milky Way and the surrounding nearby Universe."

The images were gathered by the Two-Micron All Sky Survey (2MASS), twin infrared telescopes that see wavelengths beyond red light in the rainbow of visible colors. Infrared light is emitted by humans and all objects with temperatures above absolute zero (-273 Celsius or -459 Fahrenheit). Infrared light penetrates the obscuring dust that pervades the Milky Way Galaxy, and can detect heat from very cool objects not visible with optical telescopes.

The 2MASS survey, a collaborative effort between UMass and IPAC, uses two highly automated, 51-inch (1.3-meter) diameter telescopes, one at Mount Hopkins, Ariz., the other at Cerro Tololo, Chile.

"For scientists, this computerized data represents a quantum leap from earlier infrared surveys," Cutri said. "They can study properties of all these objects, create a model of the Milky Way, and map distribution of galaxies in the local universe."

2MASS, the most extensive infrared astronomical survey to date, began operations in 1997. UMass was responsible for the development and construction of the 2MASS telescopes and cameras and manages the collection of survey data. IPAC combines and processes 2MASS images into usable data. Observations will conclude in 2001, with final processing of the data and release to the public by 2003.

Various discoveries highlight the scientific potential of the 2MASS data. For instance, astronomers had to revise a century-old classification system when 2MASS uncovered numerous stars very different from known classes of stars. They also used 2MASS data to discover the coolest known brown dwarfs, or failed stars; detect previously unknown star clusters within, and galaxies beyond, the Milky Way; discover and map regions of space where stars are born; and find a new population of galaxies, quasars, and super-massive black holes.

Part of NASA''s Origins Program, 2MASS is funded by NASA''s Office of Space Science and the National Science Foundation. 2MASS results will benefit such future Origins missions as the Space Infrared Telescope Facility and Next Generation Space Telescope, and will help scientists plan observations for the Hubble Space Telescope and the Stratospheric Observatory for Infrared Astronomy. JPL manages the program for NASA''s Office of Space Science, Washington, DC. JPL is a division of Caltech.

NOTE: Michael Skrutskie can be contacted at 413/545-2456 or skrutskie@astro.umass.edu. A parallel release is being issued today by NASA and its Jet Propulsion Lab.

A sampling of the images is posted online at http://www.ipac.caltech.edu/2mass/gallery/second/ and includes the center of our Milky Way Galaxy, the hat-shaped Sombrero Galaxy, and the Orion Nebula. Additional information about 2MASS and the latest release is available at the 2MASS/IPAC web site at http://www.ipac.caltech.edu/2mass/.