The observatory's future
Once SALT is back online, it will still be hobbled by the country's lagging telecom system, which already caused the telescope some data communication problems. While Cape Town has become a trendy, cosmopolitan city with an infrastructure more than ready to host World Cup soccer in June, South Africa overall remains a developing nation.
Charles says such optical and data-transmission issues will not permanently damage the SAAO's reputation for world-class astronomy. After all, as Buckley points out, large, state-of-the-art telescopes are often besieged by engineering glitches—to wit, Arizona's new Large Binocular Telescope is at least a year and a half behind schedule. The troubles appear not to have dampened the expectations of SALT's future users, since it has seemingly never been a question of whether the problems can be fixed, but when. Charles notes that even after the problem with the image corrector had been discovered, SALT brought in two additional partners: the American Museum of Natural History in New York City and India's Inter-University Center for Astronomy and Astrophysics.
SALT's 15 institutional partners in seven countries plan to use the observatory to study everything from asteroids to dark energy. And although partner astronomers are welcome to apply for observing time, Buckley candidly advises them not to show up expecting to oversee their own observational campaigns.
"This is a queue-schedule telescope," Buckley says. "Any one night it may be doing a dozen observational programs. So you don't want some novice asking which button to press." Astronomers using SALT will instead run remotely submitted observing programs, which advocates of this approach claim is a much more efficient way of using telescope time.
Queue scheduling means SALT can investigate objects on timescales from days to years. Its specialty will be time-domain spectroscopy—useful for observing accretion by galactic black holes, surveys of distant supernovae and even searches for extrasolar planets. As Larry Ramsey, a Penn State University astrophysicist on SALT's board of directors, says, the telescope won't try to compete with Hawaii's Keck Observatory or Chile's Very Large Telescope array but will play to its own unique strengths.
If SALT succeeds, it's good news for more than the astronomers who get observing time there. Buckley argues that the SAAO's ability to completely diagnose and repair SALT without outside help is testament to its capacity to build and run a large telescope. Meanwhile, South Africa is in competition with Australia to land the $1.5-billion SKA (Square Kilometer Array), a planned one-square-kilometer telescope comprising numerous radio dishes working in concert.
South Africa's prototype for the project is the Karoo Array Telescope (MeerKAT), an array of 80 radio antennas, each 12 meters across, that will be located 200 kilometers north of SALT. A dedicated 600-kilometer data line for MeerKAT, now under construction, will bring the telescope array's data stream to Cape Town.
It is too early to know whether South Africa will win its SKA bid, but despite a few internal squabbles, the country is taking steps to tackle its infrastructure shortcomings and its scientific need for new human capital. As for SALT, it now supercedes a 1940s-era 1.9-meter optical telescope, one of several smaller telescopes the SAAO operates at its Sutherland facility, as the largest in South Africa.
Back at Sutherland later that same evening, the visiting astronomers gather at the base of the SAAO's observing plateau, transfixed by the full swath of the Milky Way, the Southern Cross and the Magellanic Clouds before them. It's the kind of clear, moonless night that was so crucial for 15th-century European sea explorers steering their way south to the bottom of Africa. With any luck, the giant telescope will soon get up to speed, and such celestial treasure will take on wholly new scientific significance.