This theoretical gas giant was claimed to exist back in 2011 by two physics professors, John Matese and Daniel Whitmire. Actually sooner, but the mainstream attention, though met with doubt, occurred then. This planet is supposedly found in the Oort Cloud and effects the orbit of comets. It is four times the size of Jupiter and it is Planet X.
Fast forward a number of years and the telecopes are much better, the distances one can see with varied wave legnths is incredible. Enter the WISE telescope. An infrared-wavelength astronomical space telescope launched in December of 2009. (It was placed into a hibernation for a time in 2011 when its transmitter turned off) Though WISE we have discovered tge first Y Dwarf, the first Earth trojan Asteroid, tens of thousands of new asteroids, previously undiscovered star clusters, but no planet “X”. It suveyed the sky twice from 2010 to 2011 – the first time at 4 infrared wavelenghts the second time at two infrared wavelegnths. It revealed to hidden planet “X”. It did reveal 3,525 stars and brown dwarfs that were a mere 500 light years from the sun.
The expected distance of this planet “X”? Within 0.158128451 light years. While this merely a guess, since they found stars out at 500 light years, I would imiagine not even a quarter of a light year or less should be a problem. AND yet, no planet “X”.
There is the belief that plant “X” or Tyche would be not only very dim but with an orbit 15,000 times farther from the Sun than the Earth’s. None the less, not found.