PUNE, India (ABC4) — A new record has been broken in the search for signals in deep space. Scientists using the Giant Metrewave Radio Telescope in Pune, India detected a radio signal emitted by hydrogen atoms. The hydrogen is believed to be 8.8 billion years old and is the furthest radio signal of this type detected by scientists on Earth.
The findings were published in Monthly Notices of the Royal Astronomical Society in December.
Researchers from McGill University in Canada and the Indian Institute of Science said they noticed the radio signal, and that it had traveled further than any other signal ever detected.
Gravitational lensing, according to Nasa’s Hubble site, is when a huge amount of matter, like a cluster of galaxies, creates a gravitational field that distorts and magnifies the light from distant galaxies that are behind it but in the same line of sight. The effect is like looking through a giant magnifying glass. It allows researchers to study the details of early galaxies too far away to be seen with current technology and telescopes.
The radio signal the researchers encountered is weak. The signal had lengthened to 48cm. Called red shifting, this lengthening of the signal occurs the further it travels. Researchers said the signal is believed to have been sent when the universe was just 4.9 billion years old.
Until now, the most distant signal detected using this method was 4.1 billion light years away.
Does hydrogen produce a radio signal?
According to the report, hydrogen provides the basic fuel for stars. Hydrogen atoms emit a tiny bit of electromagnetic radiation called a hydrogen line or 21cm line. The radio frequency of this line is 1420.405751768(2) MHz and it’s about 21cm thick.
This line appears within the electromagnetic spectrum, is relatively weak, but easily passes through the Earth’s atmosphere. Radio astronomers look for the line while observing the cosmos and while looking for alien life.
In a 1959 paper, physicists proposed using the line to search for interstellar communications. The hydrogen line is used in many modern SETI (Search for extraterrestrial intelligence) missions.
What is the Giant Metrewave Radio Telescope?
The GMRT in India is an array of thirty parabolic radio telescopes. The telescope is designed to search for the 21cm hydrogen line. It does this to search for baby galaxies.
GMRT discovered what is believed to be the most distant galaxy in the universe, which is nearly 12 billion light years away. It also observed what is believed to be the “biggest explosion” in the history of the universe in 2020.