How scientists heard hum from the universe?

An international team of esteemed astronomers, consisting of scientists from Europe, India and Japan, have made a significant discovery by monitoring pulsars utilizing six of the world’s most sensitive radio telescopes, including upgraded Giant Metrewave Radio Telescope (uGMRT), India’s largest telescope. This is maiden use of uGMRT for detection of gravitational waves.

Findings

Using these sensitive radio telescopes scientists got to hear a “humming” or vibrations triggered by ultra-low frequency gravitational waves. These gravitational waves first envisioned by Albert Einstein are generated by dancing monster black hole pairs. These vibrations are being called nano-hertz gravitational waves.

Significance

The discovery is a momentous breakthrough in understanding the gravitational wave spectrum, and it has thrown open a new window of exploration in the field of astrophysics. It has also considerably deepened the understanding of the Universe and is a great illustration of the power of international collaboration.

What A Gopakumar said in this regard?

In this regard A Gopakumar, the chair of the Indian Pulsar Timing Array consortium & professor at TIFR, Mumbai said, “The results presented today mark the beginning of a new journey into the Universe to unveil some of these mysteries. More importantly, this is the first time that an Indian telescope’s data is used for hunting gravitational waves.”

How pulsars are monitored?

Pulsars are neutron stars rotating at very high speed. These are remnants of dead stars that emit regular radio beams while rotating. They are monitored using radio telescopes, such as India’s uGMRT.

How gravitational-wave signals get detected?

Onus of detection of gravitational-wave signals is on a collaboration called the Pulsar Timing Array (PTA). Scientists basically utilised pulsars as cosmic beacons for the PTA experiment to detect gravitational-wave signals that are light-year-scale ripples.

Team that made the discovery

The transnational team comprised of members of the European Pulsar Timing Array (EPTA) and Indian Pulsar Timing Array (InPTA) consortium. Both InPTA and EPTA are members of the International Pulsar Timing collaboration (IPTA). InPTA, an Indo-Japanese collaboration that utilises the uGMRT to monitor a sample of nearby millisecond pulsars, is a pulsar timing experiment dedicated to searching for low-frequency nanoHz gravitational waves since 2016.