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Squeezed on the scopes CMU and Pitt astronomers try to avoid being pushed aside Monday, August 28, 2000 By Byron Spice, Post-Gazette Science Editor
Ground will be broken Friday for the South African Large Telescope and, as local astronomers had hoped, Carnegie Mellon University is part of the consortium that will operate the largest telescope in the Southern Hemisphere.
That sponsorship means that Carnegie Mellon's small astrophysics group will be guaranteed observing time when construction of the big scope is complete in 2003 -- a long-sought goal.
But Richard Griffiths, who heads the astrophysics group, said the university will not be able to invest the $6 million it had originally planned to contribute and that the amount of time guaranteed to the university's astronomers will drop proportionately.
Carnegie Mellon President Jared Cohon recently signed a memorandum of understanding that commits the university to fork over at least $1 million to build and operate the scope over the next 10 years. Griffiths said the university has raised only about a quarter of that amount thus far and even that money is not yet in hand, so he is reluctant to identify the source.
A wave of telescope construction has forced university astronomy programs to scramble to win shares of large telescopes.
Over the last half-century, universities abandoned their individual observatories as new, federally sponsored observatories were constructed on distant mountaintops of Arizona and Hawaii, far from city lights, above air pollution and surrounded by dry air that minimizes optical distortion. But in the past decade, these shared facilities have been eclipsed by private telescopes, notably the giant Keck telescopes built in Hawaii for the California Institute of Technology.
To remain in the hunt for major discoveries, university astronomers have sought access to these very large instruments. That has engendered plenty of frustation among astronomers at Carnegie Mellon and the University of Pittsburgh.
Carnegie Mellon's $1 million investment will buy the university a 1/35th share of the South African Large Telescope, or SALT, which translates into a guarantee of 3 percent of its observing time.
"That's not bad, but that's pretty small," Griffiths said, explaining it's not unusual even for astronomers who don't own a piece of telescope to be granted similar amounts of time on a major telescope for specific projects.
Carnegie Mellon had originally hoped to snare 10 percent to 15 percent of the observing time. But while Griffiths searched for donors, Rutgers University pledged a couple million dollars, the University of Wisconsin committed to almost $6 million, Poland invested $3 million and additional universities and nations joined as sponsors. South Africa, of course, has financed the biggest share of SALT, investing $10 million. Construction of the telescope near Sutherland, South Africa, and its first 10 years of operations are expected to cost $29 million.
SALT will be a near-twin to the Hobby-Eberly Telescope, which is housed at McDonald Observatory in Texas and is operated by a consortium that includes Penn State University as a major partner. It will have a giant, segmented mirror measuring 11 meters across that is capable of detecting the flame of a candle on the moon.
In an economy move, neither the SALT nor Hobby-Eberly scopes has a fully steerable mirror for tracking stars across the night sky. Instead, the giant primary mirrors are set at a fixed angle to the sky. Star tracking is accomplished by moving the secondary mirror -- the small mirror above the giant primary mirror on which the primary mirror focuses all of its light.
The SALT celebration among Carnegie Mellon's four astrophysics faculty might be muted, but Pitt's astronomy faculty, twice the size of CMU's, has had little to smile about after two decades of pursuing a large scope. Plans in the past decade to invest in the Magellan Telescope on Las Campanas in Chile or the controversial Large Binocular Telescope on Arizona's Mount Graham were abandoned during the tenure of Chancellor J. Dennis O'Connor.
"We'd like to have a piece of a large telescope someplace," said George Gatewood, director of Pitt's Allegheny Observatory.
The observatory is a throwback to the old era of university observatories; it has survived -- barely -- because it specializes in astrometry, the measurement of motions and distances between stars. It continues to operate, but loss of federal grants forced it to lay off two key staff members earlier this year.
Without guaranteed access to a major telescope, astronomers have trouble keeping pace with their colleagues.
"You get to look at [observational] data after someone else has plucked all the plums out of it," Gatewood said.
When Regina Schulte-Ladbeck joined the Pitt faculty eight years ago, she was confident that the university would soon be joining a major telescope consortium. Its failure to do so hasn't stopped her from continuing her work with the Hubble Space Telescope, but it places her at a disadvantage.
An astronomer who has access to a large, ground-based telescope, she explained, can use it to leverage additional time on the Hubble or other space-based telescope. Such an astronomer might find something of interest with a ground-based telescope that might merit a closer look with the Hubble, for instance.
"It's a double-whammy for a university that is not able to be part of a consortium," Schulte-Ladbeck said.
An alternative to joining a consortium would be to establish an endowment so that astronomers could buy time on the telescope of their choice, Gatewood said. Each astronomer could use the telescope that best met his or her needs, rather than compromise because the university happened to own a piece of a different scope.
It's hard to say how long Pitt can maintain a strong astronomy program without its astronomers either owning or being able to rent a large telescope, Schulte-Ladbeck said. "The best people these days go to universities that have access to large telescopes."
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