Hawaii Shines for Solar Scope

Haleakala is the favored site for the Advanced Technology Solar Telescope (ATST), a $161 million project spearheaded by the US National Solar Observatory (NSO).

The site, 3 km high atop the Hawaiian island of Maui, emerged as the frontrunner after more than two years of testing six sites around the world for clear daytime skies and low levels of atmospheric turbulence, humidity, sky brightness, dust, and aircraft contrails. “The major goals of observing and understanding magnetic fields at their fundamental spatial scales and all heights in the solar atmosphere are best fulfilled in Haleakala,” says NSO Director Stephen Keil. At 4 m in diameter, the ATST will be the world’s largest solar telescope. It will have a resolution of 0.03 arcsecond—or about 20 km on the Sun’s surface.

Assuming that environmental, cultural, cost, and other studies permit the project to proceed on Haleakala—which is already home to the University of Hawaii’s Mees Solar Observatory—construction on the ATST could begin in 2007, and the telescope could be working by 2012.

The biggest hurdles for the ATST, says Keil, “include cementing funding commitments from partners and obtaining a strong ranking in the MREFC [NSF’s major research equipment and facilities construction] queue. Given the budgetary atmosphere in [Washington] DC and at NSF in particular, this may be a challenge.”