PRATUSH Radiometer to Probe the Cosmic Dawn From the Moon
Why in the news
Details of the PRATUSH radiometer, a compact instrument planned to study the Cosmic Dawn from lunar orbit, were reported on 2 September 2025.
Key facts
- PRATUSH is a radiometer designed to explore the Cosmic Dawn, the epoch when the first stars and galaxies emerged.
- It detects the 21-cm hydrogen line, a faint radio emission from hydrogen atoms.
- The system combines an antenna, an analog receiver and a digital receiver, controlled by a single-board computer about the size of a credit card.
- A field programmable gate array (FPGA) chip processes the cosmic radio data.
- Laboratory tests showed extremely low noise, down to a few millikelvins.
About the far side of the Moon
The instrument is designed to operate from the Moon’s far side, which is a radio-quiet environment. It is shielded from interference from Earth and from distortions caused by the ionosphere, both of which would swamp such a weak signal.
Exam angle
- Keywords: Cosmic Dawn, 21-cm line, far side of the Moon, radio-quiet zone.
- Questions may ask what the instrument detects or why the far side is chosen.
- Single-board computer and FPGA are the key hardware terms.