The Giant Meter wave Radio Telescope (GMRT) in India has received a radio frequency signal from a very distant galaxy. This galaxy is 880 million light years away from Earth. This signal was emitted soon after the creation of the universe. It is expected that this will help in understanding the early universe in depth.
Astronomers have received a signal from a distant galaxy. Till now no signal had ever been received from such a distance in space. From this signal, it can be ascertained how our universe would have been formed.
The record-breaking radio frequency signal detected by the Giant Meterwave Radio Telescope (GMRT) in India came from the galaxy SDSSJ0826+5630. This galaxy is 880 million light years away from Earth. This means that this signal originated from there when the age of the universe was one-third of the current age.
The signal is a line derived from neutral hydrogen, the most fundamental element of the universe. Big Bang i.e. when the universe was formed, then this element was present in the form of fog in the whole universe. Then the early stars and galaxies were formed from it. Astronomers have long searched for signals coming from neutral hydrogen to determine how early stars glowed, but those signals were difficult to detect given the distance.
Now, new research published in the journal Monthly Notices of the Royal Astronomical Society suggests that an effect called gravitational lensing could help astronomers find evidence of neutral hydrogen.
Arnab Chakraborty, a cosmologist at McGill University in Canada and the lead author of the research, says that a galaxy emits different types of radio signals. Until now, it was only possible to capture this signal from a nearby galaxy. Due to which our knowledge was limited only to those galaxies which are close to the Earth.
The ‘Dark Age’ of the Universe
About 4 million years after the beginning of the universe, when protons and electrons first bonded with neutrons, neutral hydrogen filled the early universe in the so-called dark ages, before the early stars and galaxies formed.
Neutral hydrogen emits a wavelength of 21 cm. But using the neutral hydrogen signal to study the early universe is a difficult task, because longer-wavelength, lower-intensity signals are often lost over long distances. So far, the most distant hydrogen signal detected was 21 cm, 440 million light-years away.
Gravitational lensing allows us to peer into the past
To find the signal at twice the previous distance, the researchers turned to an effect called gravitational lensing. Nirupam Roy, associate professor of physics at the Indian Institute of Science and a co-author of the research, says that in this particular case, there is another massive object, a galaxy, between the target and the observer that has bent the signal. Researchers hope that this method can reveal how our universe was formed and how the early stars may have shone.