Astrophysicists have discovered a group of planets outside of the Milky Way for the first time, through the use of microlensing. The identified objects range from a mass of the moon to the mass of Jupiter.
The findings were published in the Astrophysical Journal Letters. The discovery was led by scientists from the University of Oklahoma. They have applied microlensing to data taken from NASA’s Chandra X-ray Observatory to focus on a galaxy known as RX J1131-1231, which is about 3.8 billion light-years away, according to CNet.
Xinyu Dai, a professor in the Homer L. Dodge Department of Physics and Astronomy, OU College of Arts and Sciences, said they are excited about the discovery. He further noted that this is the first time that anyone has identified the planets outside the Milky Way. He added that these small planets are the best candidate for signature, as they observed in this study using the microlensing technique. The team evaluated the high frequency of the signature by modeling the date to identify the mass, according to Dai.
Microlensing is a method used in detecting planets at vast distances from the planet Earth. It gauges how the gravity of the object bends the light of an aligned and even more distant object behind it.
Eduardo Guerras, one of the scientists who discovered the planets, and a postdoctoral researcher from OU, explained how powerful the extragalactic microlensing is. He further said that the galaxy is located 3.8 billion light-years away and there is no chance of identifying the planets directly, not even with the use of the best telescope. On the other hand, they were able to detect them and uncover their visibility and determine their masses. He described the discovery as “cool science,” as noted by Phys.org.
The image above, which was provided by the University of Oklahoma, shows the gravitational lens RX J1131-1231 galaxy, in which the lens galaxy is located at the core. Also seen are the four lensed background quasars. At the center of the elliptical galaxy shown in this image, there are trillions of planets. This discovery has proven that there are extragalactic planets outside the Milky Way, which was unclear decades ago.