This is the first time that scientists have discovered a signal coming from a galaxy 9 billion light years from Earth.

The radio signal was detected by Pune, India's giant VHF radio telescope.

The huge radio telescope is equipped with thirty parabolic antennas, each pointed skyward and with a diameter of about 45 meters.

This powerful telescope allowed scientists to discover the 21-centimeter line, also called the hydrogen line, a unique radio signal with a unique wavelength. This signal is produced by neutral hydrogen atoms.

Unfortunately, this strange signal was not sent by aliens. It comes from SDSSJ0826+5630, a galaxy. It is known as a “star-forming galaxy”.

The distinctive quality of the radio signal is that it was generated during a time when Earth's Milky Way was just 4.9 billion years old. The Milky Way is currently believed to be 13.8 billion years old.

As a result, it took nine billion years for the signal to reach Earth. Scientists have the opportunity to go back in time nine billion years using radio signal.

Although radio signals from other nearby galaxies have been detected, this is the most distant one yet.

The radio signal from SDSSJ0826+5630 allowed astronomers to measure the mass and abundance of gas in the galaxy. Based on this information, scientists deduce that the stars in the distant galaxy may be twice as massive as those seen from Earth.

A study on the discovery of this radio signal was published in October 2024.