CHIME is a novel radio telescope consisting of cylindrical reflectors roughly the size and shape of snowboarding half-pipes with an array of radio recievers along the focus. There are no moving parts; CHIME will measure over half the sky each day as the Earth turns.
CHIME will map the distribution of neutral Hydrogen over the redshift range from 0.8 to 2.5. These data will be used to produce a map of cosmic structure over the largest volume of the universe ever observed, with enough spatial resolution to discern the “baryon acoustic oscillations” that were imprinted on cosmic structure at early times. This three-dimensional map will enable cosmologists to better discern the cause of the Universe’s accelerating expansion.