The Oort cloud is a hypothetical area of space comprising a spherical cloud of comets which lies roughly 50,000 AU, or nearly a light year, from the Sun.
See related link for a pictorial.
The "Oort Cloud" is an area far beyond the orbits of Neptune and Pluto which may contain the left-over remnants of the birth of the solar system.
This is entirely theoretical; we have very little actual evidence of the Oort Cloud. The idea is that stray masses, very loosely bound by gravity to the distant Sun, will occasionally perturb each other and a small, icy and rocky body may be nudged into the inner solar system. When it gets close enough, the ice will start to melt and the vapor will glow - and we see a comet. Comets have to come from somewhere, and this idea makes as much sense as anything.
But we've never detected anything in the Oort Cloud, and probably won't until we manage to send space probes out to the distance where the Sun is just a bright star.
The solar system has been in existence for about 4.5 billion years, we believe. But there is NO WAY that a comet can survive for 4.5 billion years if it is diving into the inner solar system every few millennia and boiling off some of its volatile gasses. And yet, we still have comets.
In 1950, the Dutch astronomer Jan Oort proposed the idea that there must be a reservoir of comet-like objects orbiting very far from the Sun, and only occasionally does something perturb a few of these bodies and drop them into the inner solar system as comets. Oort's hypothesis was that there must be a shell or "cloud" of frozen comet nuclei way out beyond the planets, from 2000 to 50,000 AU from the Sun. Occasionally, because of gravitational perturbations between these objects or with the Sun or other stars or other stars in the galaxy, one or a few of these would be nudged into orbits that took them deeper into the solar system.
We do not have any evidence that the Oort Cloud actually exists; it is too far away, and the objects believed to be there are too small and dark to be observed even with the largest telescopes. But the idea makes sense, because if there isn't something like the Oort Cloud around the solar system, why are we still seeing comets?
EVERY BIT of evidence for the existence of the Oort Cloud is contained in the following statements:
The solar system is 4.5 billion years old. A comet can only survive a limited number of close approaches to the Sun before hitting a planet, or the Sun, or disintegrating. However, there are still comets! Therefore, there must be some vast reservoir of comet-like objects somewhere and some mechanism that causes these objects to fall into the inner solar system.
Astronomer Jan Oort assumed that the reservoir of comet-like objects waiting in deep space is probably far beyond the orbit of Pluto. In his honor, the area of unborn comets is called the Oort Cloud.
Jan Oort discovered the oort cloud in 1950.
The Oort cloud formed 4.5 BYA (billion years ago). This is evident by the fact that hypothetically it lies at the edge of the Sun's gravitational boundary.
At the moment in time there is no observational evidence of it's existence. Until such time, it will stay as a theory.
About three light years from the sun.
1 light year.
ily
That is the Oort Cloud.That is the Oort Cloud.That is the Oort Cloud.That is the Oort Cloud.
the oort cloud is mostly black
The Oort cloud.However, technically the Oort cloud IS part of our Solar System.See related link for more information.
Oort cloud
No it does not. The Oort cloud is not a planet. It is a sphere of comets around our solar system.
That is the Oort Cloud.That is the Oort Cloud.That is the Oort Cloud.That is the Oort Cloud.
the oort cloud is mostly black
The Oort cloud.However, technically the Oort cloud IS part of our Solar System.See related link for more information.
The outer Oort cloud. (The inner Oort cloud is believed to be disk-shaped.)
Oort cloud
Oort (Yes - that is what it is called)
No it does not. The Oort cloud is not a planet. It is a sphere of comets around our solar system.
sedna is located in the Oort cloud and is the farthest object from the sun that we have discovered yet.
No part of the atmosphere of any planet is any part of the Oort cloud.
No. The Oort Cloud is "leftover" mass from the formation of the Sun and the planets.
no
The Oort cloud