Another name for the Oort Cloud is the Öpik–Oort cloud, named after Dutch astronomer Jan Oort who, in 1950, proposed the existence of an outside area for the origination of comets and Estonian astronomer, Ernst Öpik, who theorized its existence.
The Oort cloud is a spherical cloud filled with icy objects that are 50,000 AU (Astronomical Units) or 7.5 km from the Sun.
To put this in perspective, this is almost ¼ of the distance to the nearest star, Proxima Centari.
The Oort cloud contains objects that are believed to be the remains of the early development of the sun and planets.
It was thought that these objects were originally part of the Kuiper belt but became scattered due to the gravitational pull of the gas giants.
The Oort cloud is so far out that it defines the cosmographical solar system boundary at the very edge of the Sun’s gravitational influence.
Objects in the Oort cloud are considered to be loosely bound to our solar system and are effected by the passing stars’ gravitational pull.
It must be noted that since there has been no close-up research on the Oort cloud, there are a lot of unsettled debates among astronomers.
One of the observations that they have had is that they have seen the orbits of such long-period comets as Halley’s Comet as a baseline for the idea that these may originate in the Oort cloud.
Other long-period objects such as Jupiter-family comets and “centaurs” are also thought to have Oort cloud origins.
The short-period comets are theorized as originating in areas outside of the Oort cloud called the scattered disc, although it is possible that some may have once been part of the Oort cloud.
Astronomers haven’t had the ability to observe the Oort cloud directly, so some of the ideas are theoretical. It is believed that the Oort cloud looks like a spherical ball with thick walls that are from 2,000-5,000 AU (0.03-0.08 light years).
To say that the Oort cloud is “big” is an understatement. Using computer models, scientists estimate that there are several trillion objects larger than 1 km in diameter and another several billion that are of various sizes.
While we can see very distant galaxies with our telescopes, the closer and smaller objects in the Oort cloud still can’t be viewed.
The James Webb Space Telescope setting are still not enough because the objects in the Oort cloud are just too faint.
To have Oort cloud direct imaging we would have to have 100 billion times better telescopes.