Towering over the island of Maui is Haleakal?, a 10,023-foot-high dormant volcano whose dramatic summit caldera draws 1.3 million tourists per year. As these visitors take in the breathtaking vista, they can't help but notice the compound of large observatories nearby — testimony to the summit's superb conditions for astronomy.
In Hawaiian culture, Haleakal? is also revered as the sacred "House of the Sun." So it's seemingly fitting that later this year astronomers hope to being construction of the world's largest and most powerful observatory dedicated to the study of our star: the Advanced Technology Solar Telescope.
On January 22nd, the National Science Foundation announced its selection of the Association of Universities for Research in Astronomy to build the ATST. The 8-year agreement totals $298 million, enough to build the observatory and four "first-light" instruments. The construction schedule will surely be helped by an immediate infusion of $146 million from the American Recovery and Reinvestment Act. (What a difference some stimulus funding makes — two years ago AURA's Solar Observatory Council had urged the NSF to scrounge up funding any way it could so that the ATST's planning could go forward.)
Boasting a primary mirror 13 feet (4 m) across and state-of-the-art adaptive optics, ATST will view the Sun with a resolution of 0.1 arcsecond, while spanning the spectrum from 350 nm in the ultraviolet to 28 mm in the far infrared. Such amazing specs should allow astronomers to make never-before-possible measurements of turbulence and magnetic fields in the photosphere, chromosphere, and even incredibly faint corona. No comparable solar scope exists today or is on engineers' drawing boards.
ATST will join a growing armada of observatories atop Haleakal?: the U.S. Air Force's 3.7-m Advanced Electro-Optical System (AEOS) and one of its GEODSS satellite-tracking complexes, and the 2-m Faulkes Telescope North. Mees Solar Observatory, erected in 1964, was the first professional observatory built on the summit.
AURA is starting to line up its construction crews, but not everyone is happy with the prospect of adding ATST's dazzling-white 143-foot-high dome to the summit. Although astronomers picked Haleakal? in 2004 from more than 70 other prospective sites and the project has passed its environmental reviews, some cultural leaders on Maui continue to oppose the ATST.
Representatives for the National Science Foundation have sought to smooth over differences with promises of funding for Maui Community College and other educational activities involving native Hawaiians. Talks with island groups are ongoing. But the project has one final hurdle: it has yet to obtained a conservation district use permit from Hawaii's Board of Land and Natural Resources, which might take months to secure.