Radio Signal From Distant, Old Galaxy Captured By Astronomers

Radio waves coming from the furthest galaxy yet seen have been picked up by astronomers. The signal was found at a particular and important wavelength called the 21-centimeter line, which is released by neutral hydrogen atoms. This particular and significant wavelength was used to detect the signal. The discovery of the hydrogen line from a galaxy that is so far and, as a result, so early in the cosmos by the Giant Metrewave Radio Telescope in India may indicate that astronomers are prepared to begin examining the birth of the oldest stars and galaxies in the universe.

When our galaxy, which is now 13.8 billion years old, was just 4.9 billion years old, a signal came from a galaxy that was in the process of producing stars and it was called SDSSJ0826+5630. Because of the signal, the scientists were able to quantify the amount of gas in the galaxy and determine that its mass is twice as much as that of the visible stars in the early part of the galaxy. Radio waves with a wavelength of 21 centimeters have only been detected coming from local and hence more recent galactic sources so far. Galaxies release electromagnetic radiation, often known as light, throughout a broad range of radio wavelengths.

It’s the same as taking a trip back in time 8.8 billion years at this point. A galaxy is capable of sending out a variety of radio waves. Our understanding has been restricted to the galaxies that are closer to Earth because, up until now, it has only been feasible to catch this specific signal from a galaxy that is nearby.

Because of the expansion of the universe, it is difficult to detect these wavelengths coming from more distant galaxies. This is because as electromagnetic radiation from early galaxies travels great distances to Earth, the expansion of the universe causes its wavelength to get stretched out, which in turn causes its energy to decrease. This implies that telescopes on Earth need a natural boost in order to observe radio waves with long wave lengths and low energy, such as the signal from the hydrogen line.

However, the team was able to accomplish the record-breaking observation by employing a phenomena that was anticipated as part of Einstein’s geometric theory of gravity, which was initially stated in 1915. This theory was a component of general relativity, which was developed by Einstein. According to the theory of general relativity, things that have mass are able to distort spacetime in a manner analogous to how placing a ball on a stretched rubber sheet would cause the ball to become heavier in the middle of the sheet. Furthermore, just like in the analogy, the larger the mass, the more severe the curvature.

According to this interpretation, an enormously huge object such as a black hole or galaxy is responsible for the severe curvature that is produced in spacetime, much as a bowling ball would be responsible for the excessive curvature that was produced in the rubber sheet when the analogy was used.

Light bends when it travels across regions of spacetime that are warped by the gravitational pull of very massive objects. When a foreground or lensing item with a great mass lies between an observer and a background source, a phenomenon known as gravitational lensing occurs. This causes the light from the background object to bend and take multiple courses through and around the lensing object. In addition to having the effect of making a single object seem in several locations in the sky, this may also have the effect of amplifying the light that is being emitted from the item.

In the instance of SDSSJ0826+5630, the radio wave signal was amplified by a galaxy that stood in between the early galaxy and the later galaxy and acted as a lensing body. Because of this, the strength of the signal is increased by a factor of thirty as a practical consequence. The group of scientists thinks that the observation of a radio signal emanating from this early galaxy’s hydrogen line proves that it is possible to monitor radio signals emanating from other distant galaxies during the early stages of the universe’s existence. This might, in turn, open up a new approach of employing long-wavelength radio telescopes to investigate the formation of stars and galaxies, as well as how the early universe developed into the cosmos that we see around us in its present age.

Susan Kowal
Susan Kowal is a serial entrepreneur, angel investor/advisor, and health enthusiast.