Oort cloud

E19351

The Oort cloud is a distant, spherical shell of icy bodies surrounding the Solar System, thought to be the source of many long-period comets.


Statements (48)

Predicate Object
instanceOf hypothetical astronomical structure
reservoir of comets
alsoKnownAs Oort cloud
surface form: "Öpik–Oort cloud"
category comet cloud
outer Solar System object
composition cometary nuclei
icy bodies
contains dormant comets
long-period comets
distanceScale interstellar scale
dynamicalRole reservoir for comets entering inner Solar System
environment outer heliosphere boundary region
evidenceType orbits of long-period comets
formationMechanism gravitational scattering by giant planets
subsequent perturbation by galactic forces
formationOrigin scattered planetesimals from early Solar System
gravitationallyBoundTo Sun
hostStar Sun
influencedBy galactic tide
molecular clouds
passing stars
innerBoundaryDistanceFromSun roughly 2,000 astronomical units
roughly 5,000 astronomical units
innerOortCloudAlsoCalled Hills cloud
liesBeyond Kuiper Belt objects
surface form: "Kuiper belt"

scattered disc
locatedIn outer Solar System
mayOverlapWith local interstellar medium
namedAfter Jan Oort
observationalStatus inferred but not directly observed as a whole
orbitalCenter Solar System barycenter
outerBoundaryDistanceFromSun possibly up to about 100,000 astronomical units
up to about 50,000 astronomical units
partOf Solar System
populationEstimate hundreds of billions of icy bodies
possibly trillions of icy bodies
proposalYear 1950
proposedBy Jan Oort
regionType trans-Neptunian region
relevance key to understanding origin of comets
shape roughly spherical
subdivision Oort cloud
surface form: "inner Oort cloud"

Oort cloud
surface form: "outer Oort cloud"
surrounds Sun
planetary region of the Solar System
thoughtToBe source of many long-period comets
uncertainty exact extent unknown
exact mass unknown

Referenced by (4)

Full triples — surface form annotated when it differs from this entity's canonical label.

Oort cloud alsoKnownAs Oort cloud
this entity surface form: "Öpik–Oort cloud"
Solar System hasComponent Oort cloud
Oort cloud subdivision Oort cloud
this entity surface form: "inner Oort cloud"
Oort cloud subdivision Oort cloud
this entity surface form: "outer Oort cloud"