oort cloud
The Oort Cloud is a distant, spherical shell of icy objects surrounding our solar system.
Noun: 1. A hypothetical, vast spherical cloud of icy objects believed to surround the solar system at an immense distance, serving as a reservoir for long-period comets.
The term is used exclusively in the context of astronomy and planetary science to describe a theoretical structure in the outer solar system. * Scientists believe the Oort Cloud is the source of comets that take thousands of years to orbit the Sun. * The existence of the Oort Cloud is inferred from the observed orbits of long-period comets. * Voyager 1 will take tens of thousands of years to reach the inner boundary of the Oort Cloud.
- The Oort Cloud is theorized to be...: This phrasing is common when discussing its hypothetical nature and proposed characteristics.
- The Oort Cloud is theorized to be the remains of the primordial solar nebula from which the planets formed.
- In Oort Cloud models...: Used when discussing scientific simulations or theoretical frameworks.
- In Oort Cloud models, stellar gravitational perturbations are crucial for sending comets inward.
- Oort Cloud object (OCO): A term for any of the hypothetical icy planetesimals residing within the Oort Cloud.
- Hill cloud or Inner Oort Cloud: A proposed disk-shaped region of icy bodies between the Kuiper Belt and the spherical Oort Cloud.
- Kuiper Belt: A nearer, disk-shaped region of icy bodies beyond Neptune, distinct from but sometimes discussed in relation to the Oort Cloud.
- Cometary reservoir: A descriptive synonym emphasizing its function.
- Öpik–Oort cloud: The full name, acknowledging astronomers Ernst Öpik and Jan Oort.
- Long-period comet: A comet originating from the Oort Cloud with an orbital period greater than 200 years.
- Gravitational perturbation: A key mechanism that disturbs Oort Cloud objects, sending them into the inner solar system.
- Hypothetical: A critical adjective often associated with the Oort Cloud, as it has not been directly observed.
The Oort Cloud is a distant, spherical shell of icy objects surrounding our solar system.
- (astronomy) a hypothetical huge collection of comets orbiting the sun far beyond the orbit of Pluto; perturbations (as by other stars) can upset a comet's orbit and may send it tumbling toward the sun