In a first, radio signal sent by 9 billion light-year away galaxy gets captured by scientists

For the first time, a radio signal sent from a galaxy, which is almost 9 billion light-years away from the Earth, has been captured, media reports said on Friday.

What is special about this signal is that it has a unique wavelength, which is known as a "21-centimeter line" or the "hydrogen line." It is reportedly emitted by neutral hydrogen atoms.

The signal was captured by the Giant Metrewave Radio Telescope in India. It means that scientists can begin probing the formation of some earliest stars and galaxies, the report said.


The signal was emitted from a "star-forming galaxy", which is titled SDSSJ0826+5630. It was emitted when the 13.8 billion-year-old Milky Way, where Earth is located, was just 4.9 billion years old, it said citing the researchers.

In a statement this week, Arnab Chakraborty, who is author and McGill University Department of Physics post-doctoral cosmologist, said, "It's the equivalent to a look-back in time of 8.8 billion years."

According to the experts, galaxies emit light across a long range of radio wavelengths. The 21-cm-wavelength radio waves were only recorded to be emitted from nearby galaxies till now.


The signal has allowed the astronomers to measure the gas content of the galaxy and also find its mass.

This determination has helped the scientists to come up to a conclusion that this far-off galaxy is double the mass of the stars which are visible from Earth, the report said.

According to an IISc statement, the astronomical distance over which such a signal has been recorded is the largest till now by a huge margin. It is the first confirmed detection of strong lensing of 21 cm emission from a galaxy.

In Monthly Notices of the Royal Astronomical Society, the findings of the study have been published.

FAQs:

1. Where is the Giant Metrewave Radio Telescope located?
   It is located near Pune, Junnar in India.
2. What is the hydrogen line?
   It is the electromagnetic radiation spectral line emitted by neutral hydrogen atoms.