SPIDER Website
SPIDER is a balloon-borne telescope designed to measure the polarization of the cosmic microwave background (CMB). Its main goal is to measure the B-mode polarization signature that would have been imprinted by gravitational waves in the very early Universe. These gravitational waves are a predicted to have been generated during Inflation, a period of exponential expansion of the Universe at its birth. SPIDER was designed to measure a large patch of the sky at multiple frequencies to distinguish this faint signal from galactic foreground radiation.

SPIDER had its first flight in January of 2015 from McMurdo Station in Antarctica. It successfully observed at 95 and 150 GHz for 16 days over 10% of the southern sky. A second flight, which will add 280 GHz receivers, is planned for December 2020.

SPIDER Website