A Mystery Revolves Around the Sun
MSNBC, Oct 7, 2000
... Two teams of researchers have proposed the existence of an unseen planet or a failed star circling the sun at a distance of more than 2 trillion miles, far beyond the orbits of the nine known planets. The theory, which seeks to explain patterns in comets paths, has been put forward in research accepted for publication in two separate journals. For some time, astronomers have noticed that the directional patterns of these comets are not completely random. And after years of study, some researchers are reporting that the patterns hint at something big out there perturbing the cometary paths. ...
No telescope has yet detected this object. But on the basis of its gravitational effect, John B. Murray, a planetary scientist at Britains Open University, speculates that the object could be a planet larger than Jupiter, the biggest of the solar systems known planets. Murray puts the objects orbit at 32,000 AU, or 2.98 trillion miles from the sun. His proposal appears in the Oct. 11 issue of the Monthly Notices of the Royal Astronomical Society. Meanwhile, researchers at the University of Louisiana at Lafayette say the object could be a planet or brown dwarf that is, a dark, failed star roughly three times the size of Jupiter and orbiting at 25,000 AU. The researchers, led by physicist John Matese, say their paper is to be published by the journal Icarus. ...
Another question: Why hasnt such an object been seen? Murray says that even a Jupiter-scale planet could not be observed at the immense distances involved. Matese and his colleagues say that their hypothetical brown dwarf wouldnt have been detected even by the Infrared Astronomical Satellite, which surveyed the heavens in 1983 but that the yet-to-be-launched Space Infrared Telescope Facility just might be able to pick it up.