The Oort Cloud is a theorized spherical shell of icy planetesimals surrounding the solar system at 2,000 to 200,000 astronomical units from the Sun, proposed by Dutch astronomer Jan Oort in 1950 to explain the steady supply of long-period comets entering the inner solar system.
Facts
Object TypeTheorized rather than directly observed; its existence is inferred from the orbits of long-period comets. Discovery YearYear Jan Oort proposed the cloud's existence; it has not been directly observed. Sources
1. Wikipedia (space and spaceflight articles)
Wikimedia Foundationen.wikipedia.org, Oort cloud, lead sectionQuote, en.wikipedia.org, Oort cloud, lead section
Oort proposed that the bodies in this cloud replenish and keep constant the number of long-period comets entering the inner Solar System.
Reader Challenges (0 open reader challenges)
No disputes yet. Spotted an error or a better source? Open the first one.
Sign in to dispute this or suggest a correction.
View At A Past Year
The atlas records no dated fact of its own for this entry, so there is no other year to choose.