The Oort Cloud

== The Oort Cloud ==
The Oort Cloud is a massive sphere comprised mostly of comets and lies some where between 1 to 2 light years from the Sun. It's existence was first hypothesized by Jan Oort in 1950, and even though it's existence has not been proven by direct observation, it is accepted among most scientist.
== Tossups ==
1) The Nice ["niece"] model traces this object's origins to scattering from Jupiter, while Damocloid asteroids are believed to have developed from objects originating here. Matese and Whitmere suppose that the planet Tyche may be located here. Julio Fernandez posits that its chief source may be the (*) scattered disc, while Richard Muller suggested that Nemesis likely existed within this location. Its inner region, more disc-shaped, is named for J. G. Hills. For 10 points, name this hypothesized spherical entity, a possible source of long-period comets vastly more distant than the Kuiper Belt.
2) The origin of this entity was modeled by Safronov and Cameron, and within 10 million years Gliese 710 will collide with it. Its disk-shaped inner portion is called the Hills cloud, and objects like Hale-Bopp are thought to originate from this region. Lying about one light-year from the sun, it is considered the outer boundary of the solar system. This region contains trans-Neptunian objects, along with the scattered disc and Kuiper belt. The hypothesized source of long-period comets, for 10 points, name this region of space named after its Dutch discoverer.
3) The Safronov and Cameron hypotheses regard this region's formation, and it was first theorized by Estonian scientist Ernst Opik. Its inner section is sometimes named for Hills, and the Nemesis theory regards a [*] brown dwarf in it. Thought to be remains of the original proto-planetary disk, this region is the origin of objects like Hale-Bopp, long-period comets. For 10 points, name this hypothetical region that extends to the gravitational edge of our solar system, just outside the Kuiper [KY-purr] belt.