From the issue dated November 15, 2002
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High-Speed Links Connect Astronomers With 2 Telescopes 7,000 Miles ApartBy FLORENCE OLSENWhen astronomers travel to an observatory, it is often the luck of the draw that decides whether they can accomplish what they signed up months earlier to try, says Peter Michaud, manager of public information and outreach for the new Gemini Observatory (http://www.gemini.edu). Atmospheric conditions at observatories are not always optimal, he notes, recalling stories of astronomers who would come year after year to an observatory and "things wouldn't match up." Now Gemini's managers foresee greater scientific productivity resulting from advances in global networking. The most recent of these has linked the second of the Gemini Observatory's two 8-meter telescopes to the Internet2 backbone network, known as Abilene. The two-site observatory, built over the past decade, has twin telescopes on different sides of the equator -- one in the Northern Hemisphere, atop Mauna Kea, in Hawaii, and the other in the Southern Hemisphere, on Cerro Pachón, in the Chilean Andes. The twin telescopes, separated by a distance of nearly 7,000 miles, were conceived from the outset to be connected by a high-speed network like that of the Internet2 project. Using them in tandem permits observations of the entire sky. And they were designed so that astronomers would be able to use them from their offices elsewhere in the world, communicating online with technicians at the two sites instead of having to travel to one or the other. "Those of us who like science think it's better to do more of it and to do it faster," according to Thomas J. Greene, who is senior director of advanced-networking-infrastructure programs at the National Science Foundation. Both of those objectives are now possible because of the new link. Grants Cover Some Costs A $2.4-million NSF grant paid for the Internet2 connection to the Gemini South telescope, in Chile, and for the link's costs for the next three years. Two years ago, separate grants of $600,000 and $340,000 from NSF paid for linking Gemini North, in Hawaii, to the Internet2 backbone. The Internet2 connection between the two telescopes was completed just as the Chilean telescope became fully operational this year, says James R. Kennedy, operations director of the $184-million observatory project. The telescope in Hawaii has been in use for about a year and a half. The project is the result of a collaboration among seven countries -- Argentina, Australia, Brazil, Britain, Canada, Chile, and the United States -- and more than 4,000 scientists from those countries. The observatory already receives six times as many proposals to use the telescopes as it can accommodate in a year, Mr. Michaud says.With the Internet2 link complete, observatory managers say that they will be able to allocate time on the telescopes more efficiently, and that participating astronomers can stay home and participate remotely. Typically, observatories allot fixed viewing times months in advance. But poor weather conditions or equipment problems can prevent the researchers -- many of whom have traveled great distances -- from collecting data on the particular celestial objects that interest them. The method enabled by Internet2, known as queue observing, ensures more-productive scheduling of the telescopes, says Mr. Kennedy. Scientists whose proposals receive the highest ranking from independent reviewers are guaranteed time on one or both of the Gemini telescopes during optimal conditions for their proposed observation, no matter when those conditions occur. When the queue-scheduling system is fully automated and debugged, astronomers will use a Web-based software tool to simulate the observation they want to make, and the simulation will tell them whether their plan is technically feasible. The proposals, with information about the weather conditions required for the observations, will then be put into queues and linked to a meteorological-modeling program that makes one- and two-day forecasts for the telescopes' mountaintop locations. The new system will mean that, instead of flying to Hawaii or Chile, scientists will receive a telephone call or an e-mail message 24 to 48 hours in advance, inviting them to participate in the observation remotely, using high-speed videoconferencing over Internet2. Rather than pace back and forth in the control room at the telescope base station, the astronomer can be in his or her laboratory, interacting with the telescope operators, getting a quick look at the celestial images as they appear on the control-room monitors, and also asking for on-the-spot adjustments -- "all the things that you would do at the telescope if you were physically there," Mr. Kennedy says. Not Everyone Is Pleased Not all scientists are thrilled about the new setup, which Gemini officials have dubbed a "cyberobservatory." Astronomers often like to be on the scene, "to get their hands on things," says Mr. Michaud. But with one night's use of the Gemini Observatory valued at $32,000, he says, it is vital to have the most efficient system for scheduling its use. In any event, few astronomers these days are actually permitted to have their hands directly on the controls of a major research telescope. The instruments have become so sophisticated that it takes trained technicians months to become proficient at operating them. And even the professional operators use computer networks to control the telescopes remotely. Conditions at 14,000 feet -- the height of Mauna Kea -- are not ideal for the clear-headed thinking that is necessary to control and troubleshoot such a complex instrument, Mr. Kennedy says. "You have only 60 percent of normal oxygen levels in your blood. It's very difficult, especially when you're in the dark and it's cold, to make good, critical decisions at that elevation." So operators control the Gemini telescopes from remote base stations below Cerro Pachón and Mauna Kea. Realistically speaking, says Mr. Michaud, "the days of the astronomer actually pushing the knobs and buttons on an observatory telescope are pretty much over." Making the connection between Gemini's telescopes in Hawaii and Chile proved difficult, taking more than two years of effort, says Julio Ibarra, director of research networking at Florida International University. It manages AmericasPath, or AmPath, an Internet exchange point for research-and-education networks in South America, Central America, Mexico, and the Caribbean. The fiber-optic connection linking the two telescopes is not a direct one across the Pacific Ocean. It takes a roundabout, but not noticeably slower, underwater route along the eastern coast of South America, to Miami, where the AmPath hub forwards data traffic from the Chilean telescope to Internet2 backbone circuits located in Atlanta. The traffic crosses the United States over the Internet2 backbone to Seattle, and then moves across the Pacific on a fiber-optic cable to Hawaii. http://chronicle.com Section: Information Technology Volume 49, Issue 12, Page A37
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Copyright © 2002 by The Chronicle of Higher Education