Indian scientists at the Raman Research Institute (RRI), Bengaluru, in collaboration with ISRO, are developing PRATUSH (Probing Reionisation of the Universe using Signal from Hydrogen), a lunar-orbit radiometer mission. PRATUSH aims to detect the faint 21-cm hydrogen signal from the Cosmic Dawn — the epoch when the first stars ignited around 180-200 million years after the Big Bang — and the Epoch of Reionisation. The instrument carries a wideband frequency-independent antenna operating in the 40-200 MHz observation range cited by RRI for early-Universe 21-cm studies. A compact single-board computer roughly the size of a credit card serves as the digital receiver. The lunar far side was chosen for its radio-quiet environment, free from Earth's radio frequency interference. PIB highlighted the mission's innovative SBC-based digital receiver.
India's PRATUSH Mission: Lunar-Orbit Radiometer to Study Cosmic Dawn
India develops PRATUSH, a lunar-orbit radiometer to detect hydrogen signals from the Cosmic Dawn era.
Key facts
- Raman Research Institute (RRI), Bengaluru, in collaboration with ISRO, is developing PRATUSH — a lunar-orbit radiometer mission
- PRATUSH aims to detect 21-cm hydrogen signal from the Cosmic Dawn (180-200 million years after Big Bang) and Epoch of Reionisation
- Instrument carries wideband frequency-independent antenna operating over 30-250 MHz with a credit-card-sized single-board computer as digital receiver
- Lunar far side chosen for radio-quiet environment, free from Earth's radio frequency interference
Mains angle
Q: Discuss the scientific importance of the RRI–ISRO PRATUSH mission in probing the Cosmic Dawn and Epoch of Reionisation from lunar orbit.
Answer (50 words):
PRATUSH, built at Raman Research Institute with ISRO, carries a wideband antenna operating between 30 and 250 megahertz to detect the faint 21-centimetre hydrogen signal from the first stars, 180-200 million years after the Big Bang. A credit-card-sized single-board computer exploits the radio-quiet lunar far side for unprecedented cosmological sensitivity.
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Source: PIB
Frequently asked questions
What is PRATUSH and what is its scientific objective?
**PRATUSH (Probing ReionizATion of the Universe using Signal from Hydrogen)** is India's proposed space-based radio telescope mission to study the **Cosmic Dawn** — the period when the first stars and galaxies formed after the Big Bang, approximately 200 million years after it.
Why will PRATUSH be placed in lunar orbit instead of Earth orbit?
**PRATUSH** will be placed in **lunar orbit** to avoid Earth's radio frequency interference (RFI) from FM radio, satellites, and human activity. The far side of the Moon provides a radio-quiet environment essential for detecting the extremely faint 21-cm hydrogen signals from Cosmic Dawn.
What is the 21-cm hydrogen line and why is it important for studying Cosmic Dawn?
The **21-cm hydrogen line** is the radio emission from neutral hydrogen atoms at a wavelength of 21 centimetres. During Cosmic Dawn, the first stars ionized surrounding hydrogen. Detecting the **redshifted 21-cm signal** allows scientists to study when and how the universe was reionized after the Big Bang.
Which Indian space agency is developing PRATUSH and when is it expected to launch?
**PRATUSH** is being developed by **ISRO (Indian Space Research Organisation)** in collaboration with the **Raman Research Institute (RRI), Bengaluru**. It is expected to be launched in the late 2020s as part of India's lunar science programme.
What is the significance of Cosmic Dawn study for understanding the universe?
Studying **Cosmic Dawn** helps scientists understand how the universe transitioned from the **Dark Ages** (after Big Bang) to the **Age of Reionization** when first stars and black holes formed, providing insights into galaxy formation, dark matter, and the fundamental physics of the early universe.
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