Planets outside the Milky Way

Exoplanets are planets outside the Solar System. NASA’s Kepler Space Telescope and some other terrestrial telescopes have detected many such aliens. As of February 1, 2020, 3900 extraterrestrials have been confirmed in 2894 planetary families. But all of these planets revolve around stars in our parent galaxy, the Milky Way.

In May 2018, astronomers at the University of Oklahoma discovered planets in another galaxy 380 million light-years from Earth. This is the first time a planet has been found in a galaxy outside the Milky Way.

The scientists made the discovery using a technique called quasar microlensing. NASA’s lunar X – ray telescope is also behind the discovery. 2000 planets orbiting the quasar named RXJ 1131-1231 have been discovered. These include planets ranging from the size of the Moon to the size of Jupiter.

Why is it so relevant?

Let us examine the relevance of this invention. The Milky Way, our parent galaxy, is a huge space. At about one million light-years in diameter, the Sun is a main sequence yellow dwarf star in the Orion Spur, 26,000 light-years from the center of the Bard Spiral galaxy. It is estimated that there are over 20,000 billion stars in the Milky Way. It is estimated that there are billions of galaxies in the universe, but no planets have been found.

This is because terrestrial and space telescopes are unable to observe such planets. The extraterrestrials discovered by the Kepler Space Telescope and other telescopes all belong to the same family of planets around other stars in the Milky Way. Such planets are detected using planetary transit technology. This method calculates the size of the planet and other features by calculating the slight decrease in the apparent magnetism of the star when an opaque object, such as a planet, passes between the star and the telescope. But this method is not suitable for finding planets at great distances.

Planets orbiting distant stars and distant galaxies are detected by means of pulsar timing, quasar microlensing, and gravitational microlensing. All of these techniques are the application of Albert Einstein’s theory of general relativity. Now let’s see how to find distant planets using these techniques. Gravitational lensing is the distortion of light from distant galaxies in space. Lensing occurs when black holes, other galaxies, dark matter, and planets are present in the path of light. The magnitude of the resulting lensing can be accurately calculated and the mass of the phenomena causing the lensing can be determined. Quasar microlensing is a more accurate monitoring method. This method can detect the presence of opaque substances that cause lensing. So far, 53 alien planets in the Milky Way have been detected using microlensing technology. But this is the first time planets have been found in another galaxy.

This discovery could lead to a great leap forward in astronomical exploration. The discovery also excites exobiologists looking for extraterrestrial life. This discovery has given the scientific community many times more excitement than it did when they first discovered extraterrestrials outside the Solar System. It would be exciting and scary at the same time to imagine that the universe is made up of planets and life on them. Even if life could be found on the planets around stars in the Milky Way itself, they would have no resemblance to terrestrial life. Then the life on the planets in another galaxy will be weirder than we can imagine.