What is the closest planet outside of the kuiper belt?

Its closest approach to the sun is seven times farther than Neptune, or 200 astronomical units (AUs). read more

The Kuiper Belt is a collection of bodies outside the orbit of Neptune that, if nothing else had happened, if Neptune hadn’t formed or if things had gone a little bit better, maybe they could have gotten together themselves and formed the next planet out beyond Neptune. read more

The object is inclined by a whopping 45 degrees to the main plane of the solar system, where most of the other planets orbit. That's why it eluded discovery: nobody was looking there until now, Brown said. Some astronomers view it as a Kuiper Belt object and not a planet. The Kuiper Belt is a region of frozen objects beyond Neptune. read more

While many asteroids are composed primarily of rock and metal, most Kuiper belt objects are composed largely of frozen volatiles (termed "ices"), such as methane, ammonia and water. The Kuiper belt is home to three officially recognized dwarf planets: Pluto, Haumea and Makemake. read more