Primeval Structure Telescope

21 Centimetre Array
21CMA pods pointing to the North Celestial Pole
Organization	National Astronomical Observatory of China
Location	Ulastai, Xinjiang, China
Coordinates	43°49′48″N 82°57′55″E / 43.83°N 82.96528°E / 43.83; 82.96528
Altitude	~2500 m
Wavelength	radio
Built	2004 - present
Angular resolution	~4 arcmin
Website	21cma.bao.ac.cn

The Primeval Structure Telescope (PaST), also called 21 Centimetre Array (21CMA), is a Chinese radio telescope array designed to detect the earliest luminous objects in the universe, including the first stars, supernova explosions, and black holes. All of these objects were strong sources of ultraviolet radiation, so they ionised the material surrounding them. The structure of this reionisation reflects the overall density structure at the redshift of luminous-object formation.

PaST will consist an array of some ten-thousand log-periodic antennas spread over several square kilometers. It will capture a detailed radio image of the sky in the range of fifty to two-hundred megahertz. The telescope is built on the high plateau of Ulastai in the west of Xinjiang province, a remote area away from most television and radios signals that may interfere the weak 21 cm background signals.

References

• Peterson, J. B.; Pen, U. L.; Wu, X. P., 2004, "The PrimevAl Structure Telescope".
• Pen, U. L.; Wu, X. P.; Peterson, J. B., 2004, "Forecast for Epoch-of-Reionization as Viewable by the PrimevAl Structure Telescope (PAST)", Chinese Journal of Astronomy and Astrophysics.