Changes

In 1950, astronomer [[Jan Oort]] first proposed the existence of a "cloud of comets" in the outer fringes of the solar system.<ref name=Sonoma>Tenn, Joseph S. "[http://www.phys-astro.sonoma.edu/BruceMedalists/Oort/ The Bruce Medalists: Jan Hendrik Oort]." Department of Physics and Astronomy, Sonoma State University, October 11, 2006. Accessed June 2, 2008.</ref><ref name=Oort>Oort, J.H., 1950. The structure of the cometary cloud surrounding the solar system and a hypothesis concerning its origin. Bulletin of Astronomy of the Netherlands, 11:91–110.</ref> Oort calculated that this cloud might contain a trillion comets.<ref name=Arnett/> Short-period comets are supposed to come from the [[Kuiper Belt]].<ref name=Weisstein/><ref name=Faulkner1/><ref name=Arnett/><ref name=Harvey>Harvey, Samantha. "[http://solarsystem.nasa.gov/planets/profile.cfm?Object=OortCloud&Display=OverviewLong Solar System Exploration: Oort Cloud]." [[National Aeronautics and Space Administration|NASA]], March 29, 2006. Accessed June 2, 2008.</ref> Oort originally speculated that the total mass of the Oort cloud would be as much as the mass of [[Jupiter]]. More recent studies have suggested that the total mass might be forty times the mass of the earth.<ref name=Faulkner2/>

In 1950, astronomer [[Jan Oort]] first proposed the existence of a "cloud of comets" in the outer fringes of the solar system.<ref name=Sonoma>Tenn, Joseph S. "[http://www.phys-astro.sonoma.edu/BruceMedalists/Oort/ The Bruce Medalists: Jan Hendrik Oort]." Department of Physics and Astronomy, Sonoma State University, October 11, 2006. Accessed June 2, 2008.</ref><ref name=Oort>Oort, J.H., 1950. The structure of the cometary cloud surrounding the solar system and a hypothesis concerning its origin. Bulletin of Astronomy of the Netherlands, 11:91–110.</ref> Oort calculated that this cloud might contain a trillion comets.<ref name=Arnett/> Short-period comets are supposed to come from the [[Kuiper Belt]].<ref name=Weisstein/><ref name=Faulkner1/><ref name=Arnett/><ref name=Harvey>Harvey, Samantha. "[http://solarsystem.nasa.gov/planets/profile.cfm?Object=OortCloud&Display=OverviewLong Solar System Exploration: Oort Cloud]." [[National Aeronautics and Space Administration|NASA]], March 29, 2006. Accessed June 2, 2008.</ref> Oort originally speculated that the total mass of the Oort cloud would be as much as the mass of [[Jupiter]]. More recent studies have suggested that the total mass might be forty times the mass of the earth.<ref name=Faulkner2/>

==Observable Bodies in the Oort Cloud==

==Observable Bodies in the Oort Cloud==

The Oort Cloud is primarily composed of very faint comets, which are not detectable by telescopes on earth. However, a number of larger objects resembling comets in composition have been discovered. To date these Trans-Neptunian objects are as follows:

The Oort Cloud is allegedly primarily composed of very faint comets, which are not detectable by telescopes on earth. However, a number of larger objects resembling comets in composition have been discovered. To date these Trans-Neptunian objects are as follows:

*90377 Sedna, an object from the inner Oort cloud. It's highly elliptical orbit is among the largest in the solar system, barring comets.<ref>http://science1.nasa.gov/science-news/science-at-nasa/2004/16mar_sedna/ accessed 5/25/2013</ref>

*90377 Sedna, an object from the inner Oort cloud. It's highly elliptical orbit is among the largest in the solar system, barring comets.<ref>http://science1.nasa.gov/science-news/science-at-nasa/2004/16mar_sedna/ accessed 5/25/2013</ref>

*136108 Haumea, an object from the Kuiper belt, not strictly an Oort Cloud object. It's elongated shape is of interest to astronomers and others.

*136108 Haumea, an object from the Kuiper belt, not strictly an Oort Cloud object. It's elongated shape is of interest to astronomers and others.

*Eris, the most massive trans-neptunian object. It is 27% more massive than Pluto, and has one moon, Dysomnia.

*Eris, the most massive trans-neptunian object. It is 27% more massive than Pluto, and has one moon, Dysomnia.

*Long period Comets. They tend to have highly elliptical orbits, similar to that of 90377 Sedna, and have enormous orbital periods.

*Long period Comets. They tend to have highly elliptical orbits, similar to that of 90377 Sedna, and have enormous orbital periods.

== Problems with the Oort Cloud Hypothesis ==

== Problems with the Oort Cloud Hypothesis ==

# The Oort cloud itself has never been directly observed. Most astronomers believe that individual comets would be unobservable so far away.<ref name=Faulkner1/><ref name=Arnett/>  

# The Oort cloud itself has never been directly observed. Most astronomers believe that individual comets would be unobservable so far away.<ref name=Faulkner1/><ref name=Arnett/>