There are a lot of things in the universe that routinely stump scientists trying to understand how everything in it works. And joining the long list is OGLE-2016-BLG-1190Lb, a planetary object so massive the team behind its discovery isn’t even sure if it is a gigantic planet or a failed star.
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The planet itself has a mass equivalent to about 13.4 times that of Jupiter, and it orbits its host star approximately every 3 years at a distance of 2 AU (one astronomical unit is the distance between the sun and Earth, roughly 150 million kilometers or 92 million miles). The star, OGLE-2016-BLG-1190L, is a G dwarf with only about 0.89 solar masses, or less than a tenth of the sun.
The mass of the planet places it almost exactly at the conventional boundary that separates planets from brown dwarfs, and this is why scientists cannot determine whether it is, in fact, a planet that was born out of the disk around its host star or if it is a low-mass failed star.