A microlensing event revealed the possible existence of a massive exoplanet at the core of the Milky Way.
(Mirror Daily, United States) – According to a new report, a microlensing event has allowed scientists to detect a massive exoplanet in the central core of the Milky Way galaxy.
The planet was discovered by the Korea Astronomy and Space Science Institute, which based its findings on observations from the Spitzer Space Telescope and Optical Gravitational Lensing Experiment (OGLE) used by NASA. A study paper with their findings was published on October 27, 2017.
The Massive Exoplanet and its Location
Dubbed OGLE-2016-BLG-1190Lb, the new planet is 13.4 times the size of Jupiter. This is considered the largest that a planet can get before becoming a star. Because of this, one of the emerging theories is that OGLE-2016-BLG-1190Lb may actually be a brown dwarf with low mass. It orbits a G dwarf star that is about 0.89 times the size of our planet’s Sun, at a distance of about 2.0 AU (twice as far as the Earth is from the sun).
The massive exoplanet is located in the central core, a bulge in the center of the Milky Way that is mostly filled with stars. This is a chaotic region where it is difficult to detect any planets through conventional means. However, this massive exoplanet was detected thanks to a microlensing event.
Such an event occurs when one star passes in front of another. The gravity of the star closer to the Earth then bends the light of the other star, magnifying it. In this case, OGLE-2016-BLG-1190Lb was orbiting the closer star, and thus blocked the light of the more distant star. Thus, scientists were able to calculate its properties based on how much light was blocked and for how long.
Because it relies on stars moving in front of each other, microlensing is a very slow process.
The central core region which includes this planet is located about 22,000 light years away from the Earth.
Image Source: Exoplanets.NASA.gov