The discovery of a new planet may not be too special. However, this time the planets discovered by astrophysicists are very special because they are outside the Milky Way galaxy.
Previously, the planets that were detected only within the Milky Way galaxy.
"We are very excited about this discovery, this is the first time anyone has discovered a planet outside our galaxy," said Professor Xinyu Dai, an astrophysicist at the University of Oklahoma.
The findings, published in The Astrophysical Journal, were conducted using a technique called microlensing. This technique utilizes the brightness of distant celestial bodies such as stars and quasars (galactic nuclei).
This microlensing technique is the only known method capable of identifying planets at such distances. With this technique too, scientists can identify a group of distant worlds only by using data from NASA's Chandra X-ray Observatory.
"This is an example of how powerful an extraglactic microlensing analysis technique (outside the Milky Way galaxy)," said Dr Eduardo Guerras, Dai's associate in the findings.
The newly discovered planet is estimated to have a size ranging from the moon to the size of Jupiter. In addition, the galaxy's distance is approximately 3.8 billion light-years from the Milky Way.
"This galaxy lies 3.8 billion light years away, and there is no possibility to observe these planets directly, even with the best telescopes imaginable in science fiction scenarios," Guerras said.
"However, we can learn it, uncover their presence and even have an idea of the size of their masses." The science is very cool, "he added.
Microlensing is an astronomical effect in which light derived from distant stars or quasars is deflected by the gravity of intermediate objects such as other stars or black holes when viewed from the earth.
If the light source is positioned just behind the intermediate, the object will act as "lens". Furthermore, the lens makes the disc of light when the light from the source passes through all sides.
The brightness of this disc is influenced by the presence of planets near the lens star. This is then used to determine the existence of the planet that should be too distant to recognize.
This effect has been predicted by Einstein's theory of relativity. Therefore, these light discs are also known as "Einstein discs".
In his report, Professors Dai and Dr. Guerras mentioned that they used the telescope to study the nature of the background emissions microcompensation of quasars. They then used to make measurements that were identified as evidence of planets outside the galaxy.
"These small planets are the best candidates of the peculiarities we observed in this study using microlensing techniques," says Professor Dai.
"We analyze a typical high frequency by modeling the data to determine the mass," he concluded.
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