March 9, 2004

Cornell and Caltech agree to study building of new sub-millimeter telescope on high mountain plateau in Chile

Cerro Negro in Chile
Riccardo Giovanelli/Cornell University
HIGH AND DRY. The summit of Cerro Negro in Chile's Atacama Desert, one possible site for the proposed Cornell-Caltech 25-meter infrared telescope.

Cornell University and the California Institute of Technology (Caltech) have signed an agreement committing the two institutions to collaborate on the planning for a 25-meter infrared telescope high in the Atacama Desert of northern Chile.

The universities will focus on the first phase of telescope development, says Riccardo Giovanelli, professor of astronomy at Cornell and project director. During the $2 million study phase, Cornell and Caltech researchers will outline the technical and financial resources required to construct the new telescope. Fred Young, an active Cornell alumnus and retired businessman from Racine, Wisc., will fund most of Cornell's share of the study.

The estimated total cost of the telescope will be $60 million and is expected see "first light" in 2012. The Atacama site, about 1,000 miles north of Santiago, is more than 5,000 meters (16,500 feet) above sea level.

The Atacama telescope will be sensitive to light with wavelengths longer than 200 microns, or 0.2 millimeters. These wavelengths (called far-infrared or sub-millimeter) are too long to be perceived by the human eye, but are shorter than the waves that transmit radio and television signals.

Because these waves are absorbed by water vapor in the Earth's atmosphere, they are difficult to detect from the ground. The high Atacama Desert will position the telescope above most of the water vapor in the atmosphere, making the site one of the best on Earth for far-infrared astronomy.

The new telescope will be "by far the most sensitive sub-millimeter telescope in the world," says Cornell astronomy professor Gordon Stacey, who studies infrared astronomy and instrumentation and has been a major advocate for the project. Because the telescope will be so sensitive -- 30 times more sensitive than current sub-millimeter telescopes -- it will be able to probe star formation during the epoch of galaxy formation, the time in the universe's history at which galaxies first appeared, says Stacey.

Cornell and Caltech researchers also will use the new telescope to study the origin of the large-scale structure of the universe, a filamentary web that Giovanelli describes as a "bowl of spaghetti." Also on the telescope's agenda are circumstellar disks, the rotating pancakes of dust and gas in which planets form. These planetary nurseries are shrouded from optical telescopes by light-absorbing dust, but they emit an infrared glow that could reveal hidden planets.

Giovanelli notes that the telescope will take advantage of the "coming of age" of new sub-millimeter detector technology. Called large format bolometer arrays, these detectors will sensitively measure radiation collected by the telescope over tens of thousands of pixels. Current detectors have only a few hundred pixels and, just as with digital cameras or computer monitors, more pixels create sharper images.

A steering committee, headed by Giovanelli and staffed by four members from both participating universities will direct the project. The study phase is expected to be complete in two years or less, followed by engineering development and construction.

"Caltech is just a wonderful partner, with their long history in sub-millimeter astronomy," says Stacey. Though the agreement does not formally commit Cornell and Caltech to collaboration beyond the study phase, Giovanelli notes that it spells out the universities' intentions to work together to bring the project to completion.

This release was reported and written by Cornell News Service science writer intern Kate Becker.