POLARBEAR

POLARBEAR is a radio telescope with a 2.5-meter diameter positioned at Cerro Toco in the Atacama Desert. The instrument observes the cosmic microwave background at 150 GHz frequency to detect radiation patterns from the early universe.

The telescope was originally developed in California and relocated to the Atacama Desert in 2012 to benefit from exceptionally dry conditions. This move enabled more precise measurements of the cosmic microwave background from the southern hemisphere.

Scientists from multiple international institutions collaborate at this facility to advance understanding of the early universe through cosmic microwave background measurements.

The equipment sits at 5,200 meters elevation where the extremely dry atmosphere creates optimal observation conditions. Visitors should prepare for high altitude and a harsh, exposed location.

The instrument has measured polarized patterns in the cosmic background radiation, providing clues about gravitational lensing effects. This discovery helped confirm theoretical predictions about how matter bends light from the distant universe.

Location: Atacama Desert

Elevation above the sea: 5,200 m

Diameter: 2.5 m

Part of: Simons Array

Website: http://bolo.berkeley.edu/polarbear

GPS coordinates: -22.95806,-67.78622

Latest update: December 10, 2025 20:02