This Brown Dwarf.

Its position just beyond Pluto suggests it is at its closest approach to the Sun and Earth. [2][4] As of 2012[update], more than 1800 brown dwarfs have been identified. The group made the rounds of all the news web sites in the past two weeks, claiming they discovered something very significant. [14], Using newer and more powerful infrared telescope technology which is able to detect brown dwarfs as cool as 150 kelvins out to a distance of 10 light-years from the Sun,[15] the Wide-field Infrared Survey Explorer (WISE survey) has not detected Nemesis. The 2MASS astronomical survey, which ran from 1997 to 2001, failed to detect a star, or brown dwarf, in the Solar System. G1.9 was first identified as a "supernova remnant" in 1984 by Dave Green of the University of Cambridge and later studied in greater detail with NRAO's Very Large Array radio telescope in 1985. First we'll explain WHAT these astronomers have discovered.

Knowing that supernova do not expand this quickly, unless they have just exploded, they explained that G1.9 must be a "very young" supernova -- perhaps not more than 150 years old. All matter attracts other matter. Sometimes a solid sphere will attract some of the gas that is in the disk and this will result in a gaseous giant, like Jupiter and Saturn, which has a solid core but a thick gaseous atmosphere. [16][17] In 2011, David Morrison, a senior scientist at NASA known for his work in risk assessment of near Earth objects, has written that there is no confidence in the existence of an object like Nemesis, since it should have been detected in infrared sky surveys. Scientists at places like NASA and famous observatories have deflected inquiries about the discovery for a few years now, mainly because they feared being associated with these "fringe" theories. It had grown in size by 16%. A larger mass will attract smaller masses towards it.
Jupiter and Saturn are extremely massive and have such strong gravity that they attract meteors and comets entering the planetary zone of our Solar System.

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The mythological Nemesis was the spirit of divine retribution against those who succumb to hubris, vengeful fate personified as a remorseless goddess. In space this results in growing clouds of matter that tend to clump together and attract more matter. Scientists believe that the minimum mass needed to ignite a sun is about 13 times the known mass of the planet Jupiter -- written as "13MJ."