Mount Wilson Observatory Virtual Tour
CHARA Interferometer Array

The flagship project of Georgia State University's Center for High Angular Resolution Astronomy (CHARA) is its optical/interferometric array of six telescopes located on Mount Wilson. Each telescope of the CHARA Array has a light-collecting mirror 1-meter in diameter. The telescopes are dispersed over the mountain to provide a two-dimensional layout that provides the resolving capability (but not the light collecting ability!) of a single telescope a fifth of a mile in diameter. Light from the individual telescopes is conveyed through vacuum tubes to a central Beam Synthesis Facility in which the six beams are combined together. When the paths of the individual beams are matched to an accuracy of less than one micron, after the light traverses distances of hundreds of meters, the Array then acts like a single coherent telescope for the purposes of achieving exceptionally high angular resolution. When fully operational, the Array will be capable of resolving details as small as 200 micro-arcseconds, equivalent to the angular size of a nickel seen from a distance of 10,000 miles (over 100 times the resolving power of the Hubble Space Telescope). In terms of the number and size of its individual telescopes, its ability to operate at visible and near infrared wavelengths, and its longest baselines of 350 meters, the CHARA Array is arguably the most powerful instrument of its kind in the world.

Antipicated areas of study for the CHARA array include:

• Features on other stars similar to spots and flares on the Sun
• Matter streaming between close pairs of stars
• Expanding shells blown away by exploding stars
• Stars condensing from primordial gas and dust
• Stars swarming around super-massive black holes in galactic nuclei
• Planets in other solar systems