Giant Exoplanet 13 Times Larger Than Jupiter Found Hidden In The Middle Of Our Galaxy

Astronomers spotted a monster-planet of massive proportions tucked away in the center of The Milky Way, and the surprise keeps getting bigger as the mystery unfolds and more puzzling details come to light.

The giant exoplanet was first sighted last June by the Optical Gravitational Lensing Experiment (OGLE), through a technique called microlensing. Normally, astronomers can detect either bright objects with a high luminosity, or large bodies that pass in front of a light source and become visible by blocking it. Microlensing, however, relies on the light of background stars, which it uses pretty much like a flashlight in the dark.

When a star comes in front of another star, its gravitational pull bends the light of the star remaining in the background, essentially magnifying it. This is called a microlensing event and it helps shed the light (pun intended) on any planets that might be orbiting the closer star. Such planets would immediately become visible when they block the light of the magnified star in the background of their parent star.

This method comes in handy when astronomers are trying to locate celestial bodies thousands of light-years away, which are otherwise difficult to detect. This is precisely the case with the newly discovered exoplanet, which, Phys.org reports, was identified as a microlensing event by OGLE’s 1.3 meter Warsaw telescope, stationed in the Las Campanas observatory in Chile.

Massive new exoplanet found in Milky Way's central core – https://t.co/FDtV89EibK via https://t.co/kFnSX9E9zw

— Aaron ?????????? (@aaronyazejy) November 7, 2017

A few days after the discovery, NASA’s Spitzer Space Telescope also observed this microlensing event. Recently, the Spitzer observations have been analyzed by a team of astronomers from the Korea Astronomy and Space Science Institute (KASI) in Daejon, South Korea.

The researchers, led by Yoon-Hyun Ryu, from KASI’s Optical Astronomy Division, are now saying last year’s discovery was actually a gigantic exoplanet orbiting a dwarf star near the center of The Milky Way. The astronomers explained this in a paper, recently featured on the arXiv physics server and submitted to The Astrophysical Journal on October 27.

This massive exoplanet is truly baffling for a number of reasons and astronomers can’t wait to unravel its secrets. Here’s why.

The first striking thing about this strange exoplanet is its gargantuan size. The giant planet, dubbed OGLE-2016-BLG-1190Lb (a long, imposing name to match its overwhelming proportions), has a mass roughly 13.4 times larger than Jupiter.

Then, there’s talk it might not even be a planet after all. The researchers argue this huge exoplanet is big enough to be a tiny star. Its impressive mass places OGLE-2016-BLG-1190Lb right at the boundary between planets and brown dwarfs, also known as the deuterium burning limit and established at 13 Jupiter masses.

So astronomers are still unsure how to classify this strange object, since they can’t ascertain its precise size. Therefore, there is a strong possibility the giant planet could turn out to be a low-mass brown dwarf.

Another bizarre thing about OGLE-2016-BLG-1190Lb is where it was encountered. The massive exoplanet (or minuscule brown dwarf, as it were) was found hidden in the center of the Milky Way, in an area known as the galactic “bulge” — a chaotic place crowded with stars, where planets are seldom ever detected due to the sheer distance from Earth and their lack of luminosity.

OGLE-2016-BLG-1190Lb sits 22,000 light-years away from our home planet. Its parent star is a G dwarf, slightly smaller than our sun, which it orbits roughly every three years, at a distance of 2 AU — double the one between the Earth and the Sun.

This makes OGLE-2016-BLG-1190Lb one of the most distant exoplanets ever discovered. According to Ryu’s team, it is also the first exoplanet detected with the help of microlensing and the Spitzer spacecraft.

But what researchers are most adamant to uncover is how this peculiar object was formed — whether by cosmic debris clunking together and giving rise to planets, or by the breakdown of a giant gas cloud into stars. This is the exoplanet’s biggest mystery, yet to be revealed. The astronomers point out OGLE-2016-BLG-1190Lb is right at the edge of the brown dwarf desert, which really means thing could have gone either way.

“Since the existence of the brown dwarf desert is the signature of different formation mechanisms for stars and planets, the extremely close proximity of OGLE-2016-BLG-1190Lb to this desert raises the question of whether it is truly a ‘planet’ (by formation mechanism) and therefore reacts back upon its role tracing the galactic distribution of planets,” Ryu’s team writes in their paper.

[Featured Image by Alex Mit/Shutterstock]