New Mauna Kea telescope to be dedicated

By Kevin Dayton
Advertiser Big Island Bureau

HILO, Hawai'i — Scientists are gathering at the summit of Mauna Kea today for the dedication of the completed Submillimeter Array, a new telescope astronomers hope will allow them to see new solar systems forming around distant stars.

Astronomers also plan to use the new imaging telescope to monitor the weather on Mars and other planets and moons, study dusty areas of the galaxy where stars form, and study newborn stars to try to learn how plants are created.

The $80 million array is made up of eight 20-foot antennas that function as one giant telescope, discerning images at submillimeter wave lengths.

Working together, those antennas will be able to detect objects 30 times smaller than can be seen with either of the earlier generation submillimeter telescopes on Mauna Kea, which are the Caltech Submillimeter Observatory, and the James Clerk Maxwell Telescope.

The Submillimeter Array is particularly well suited for peering into huge clouds of cold gas and dust to look at the "nursery" for planets and stars, said Antony Schinckel, director of operations for the Submillimeter Array.

"We think we're going to actually be able to see stellar and planetary formation going on, but we don't know that," Schinckel said.

"That's the exciting thing about this instrument: There's never been a telescope exactly like this built before, so the science we think we're going to be doing in the next few years, in five years' time we may be doing something quite different," he said.

Astronomical events such as creations of stars and planets generate electromagnetic radiation that travels at various wave lengths, including visible light.

The submillimeter wave length range is much longer than the wave length of visible light. The submillimeter band is between the radio and infrared wave lengths, and is the last band to be studied.

Technology called interferometry will link up the antennas and organize the data collected by each into images. The combination of submillimeter observations linked by interferometry is brand new, Schinckel said.

To arrange the telescope for the best viewing of specific features in the sky, a truck will pick up the antennas and move them along dirt roads among 24 pads atop Mauna Kea.

Alison Peck, an astronomer with the array, said the telescope will allow astronomers to obtain images of the gas clouds where stars are beginning to form. That should help answer questions about how the clouds contract into stars without collapsing or breaking up, she said.

The telescope is also important for mapping the sky, she said.

The oldest galaxies that formed near the beginning of the universe are very bright at submillimeter wave lengths, but faint at optical wave lengths. It is often difficult to match optical light or X-ray observations of those galaxies with the submillimeter observations.

Peck said the array will help with that, determining the precise locations of the oldest galaxies in the sky so they can be compared with data from other telescopes, she said.

Scientists have been testing and adjusting the last of the antennas over the past month, and Schinckel said the observation schedule will gradually ramp up over the next year to take full advantage of the eight antennas.

Scientists had a long wait for completion of the project: The ground breaking for the array was in 1995, although the array has been operating for years with fewer than its full complement of eight antennas.

The project is a joint effort by the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics In Taiwan. The University of Hawai'i contributed the site for the project 13,600 feet above sea level, and the three organizations will share in the use of the observatory.

The array costs about $8.5 million a year to operate, and has a staff of 38 based in Hilo.

Initially most of the operations will be run from the summit or from Hilo, but in the future the telescope will also be operated from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., and Taipei, Taiwan.

Reach Kevin Dayton at kdayton@honoluluadvertiser.com or (808) 935-3916.