Tour Home

Welcome to MWO

The Museum

150-ft Solar Tower

60-ft Solar Tower

Snow Telescope

60-inch Telescope

100-in Telescope

Berkeley Interferometer

CHARA Array

The Galley

Michelson Site

The Monastery

MWO Homepage


The Infrared Spatial Interferometer


The Infrared Spatial Interferometer (ISI) is operated by the University of California at Berkeley. The ISI system consists of three 65-inch telescopes, all mounted in separate trailers to allow them to be spaced at different distances and angles from each other.

The ISI telescopes, spaced up to 85 meters apart, observe the sky at mid-infrared wavelengths and combine the starlight received in the individual telescopes. High-resolution images of red-giant and Mira-type variable stars can be constructed from the combined starlight. The incoming starlight from each telescope is mixed with laser light before being combined. This allows the instrument to work more like a radio astronomical interferometer than an optical interferometer.

The ISI website contains much more information about this unique instrument.