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Cosmology Large Angular Scale Surveyor (CLASS)

Two telescope structures stand in front of a starry night sky.
Cosmology Large Angular Scale Surveyor (CLASS)
Credit: Matthew Petroff at JHU/CLASS

Telescope Details



Atacama Desert in Chile


CLASS will image the cosmic microwave background, detecting patterns from the early inflation of the universe and the formation of stars and galaxies. CLASS will map more than 70% of the sky. 

NIST’s role:

Provided electronics. 

Significant discoveries:

Demonstrated a novel signal modulation technique in an effort to reduce systemic errors to improve data quality and fidelity. 

Other interesting facts:

At 5,200 meters (17,000 feet), it's one of the highest telescopes in the world. The high and dry site limits the negative impacts of microwave emissions from water and oxygen molecules in the atmosphere.

Supported by:

National Science Foundation and NASA

Operated by:

Johns Hopkins University

Other team institutions:

NASA Goddard Space Flight Center, University of British Columbia, Harvard-Smithsonian Center for Astrophysics, Pontificia Universidad de Chile, Universidad de Chile, University of Michigan and Villanova University


A rectangular array of chips is gray with yellow squares in the corners.
NIST electronics chips
Credit: NIST
Created October 1, 2021, Updated November 3, 2021