We will be having our next city meetup on 2026-08-02T10:00:00Z→2026-08-02T12:30:00Z.
Shouvik Sarkar, a PhD scholar from IIT Madras will give a talk titled “Listening to the First Billion Years of the Universe: Searching for the 21-cm Signal with the Murchison Widefield Array”.
We are splitting the venue charges among us attendees and we expect it to be around Rs. 200. Please register using this page - Events - Chennai Astronomy Club
Venue details will be shared once you make the payment but it’s located in Royapettah. Since there are limited seats available in the venue, please register as soon as you can.
Talk Description:
What was the Universe like before the first stars and galaxies lit up the cosmos? One of the most promising ways to answer this question is by searching for a very faint radio signal emitted by neutral hydrogen, the most abundant element in the Universe. As this signal has travelled across billions of years, the expansion of the Universe has stretched it to longer wavelengths, making it observable today with radio telescopes.
Detecting this ancient signal is an enormous challenge because it is buried beneath much brighter radio emission from our own Galaxy and other astronomical sources. In addition, imperfections in the telescope and the Earth’s environment make the search even more difficult.
In this talk, I will introduce the story of the early Universe and explain how radio astronomers are trying to detect this faint signal from the cosmic past. I will describe the Murchison Widefield Array (MWA), a powerful radio telescope in the radio-quiet deserts of Western Australia that has been specially designed to search for this signal. Finally, I will present our group’s latest work using MWA observations to improve the search for the elusive 21-cm signal from a time when the first stars and galaxies transformed the Universe, bringing us one step closer to uncovering this important chapter in cosmic history.
