Telescope May Find Light From Earliest Galaxies

"Surveys tell you how individual stars and galaxies fit into a larger picture," Nordsieck said. "There's great interest among astronomers in how the strange-looking objects we see at great distances, which were present at the beginning of the universe, turn into the galaxies and stars of today."

Nordsieck designed SALT's main instrument: the Robert Stobie Spectrograph (named after the late director of the South African Astronomical Observatory that runs SALT), which splits light into its component wavelengths, or spectra.

Unlike those on most other telescopes, SALT's spectrograph has a "polarimetric mode" that allows for observations in the ultraviolet range. This makes it possible to investigate magnetic fields surrounding stars and galaxies, and to measure features that can't ordinarily be seen, such as the shapes of exploding stars and the trajectories of luminous gases and dust.

The spectrograph also has a unique high-speed mode that can reveal, for instance, how particles behave just before being sucked into black holes. "These are the kinds of data that could allow us to test Albert Einstein's theory of relativity," said Phil Charles, SALT's director. "And that's one of our ultimate goals."

SALT astronomers are preparing to start construction of a second spectrograph, which will complete the telescope's initial suite of instruments. This $2.5 million high-resolution device will offer even more precise spectral measurements. It was designed by a group led by Peter Cottrell of the University of Canterbury in New Zealand and is scheduled to arrive in South Africa in 2008. This instrument is expected to be able to detect motions of just a few meters per second, such as those produced by unseen planets pulling on their host stars.

With it, astronomers will be able to hunt for new planets, which is big business in astronomy, noted Alex Wolszczan, professor of astronomy and astrophysics at Pennsylvania State University.

Charles said it could be a year before SALT becomes fully operational. But the telescope has produced its "first light" images, including pictures of the Lagoon Nebula, a giant interstellar cloud 5,200 light-years from Earth; and 47 Tucanae, a spectacular cluster of 100,000 stars thought to be among the oldest in the universe.

SALT is already a boon for South Africa. It was built by a six-nation consortium, with South Africa as the leading member with a one-third share. The project's foreign partners paid two-thirds of the $20 million cost, and most of that was spent in South Africa, Naidoo said.

"Instruments like those on SALT are rare, so the best astronomers in the world are coming to South Africa to work," he said. "And they're helping us train our own next generation of astrophysicists. Ten years ago, a black scientist in a major institution like SALT would have been unheard of in South Africa. Now that's a reality. So, this has the broader impact of empowering a nation -- of helping people with a history of oppression make the transition to being normal citizens in society."