Inferred outer reservoir · comet source
Oort cloud
A theorised shell so distant that the Sun becomes one star among many.
The Oort Cloud is an inferred, extremely distant reservoir of icy bodies surrounding the planetary system. No spacecraft has imaged the cloud as a whole; its existence and structure are inferred primarily from the orbits of long-period comets.
- Spatial representation
- Inferred schematic context
- Visual representation
- Sparse distant shell
Reference measurements
What is estimated, inferred and compressed
- Estimated inner edge
- 2,000–5,000 AUNASA reference range; not a measured solid boundary.
- Estimated outer edge
- 10,000–100,000 AUNASA reference range; the inferred boundary remains uncertain.
- Geometry
- Roughly spherical shell
- Evidence basis
- Long-period comet orbits
- Direct global image
- None
- Context particles
- 1,650A stable schematic sample.
- Scene scale
- Strongly compressed
Evidence
A region reconstructed from visitors
Long-period comets arrive from many directions and follow extremely extended paths. Their orbital distribution supports the idea of a distant, approximately spherical source reservoir, but it does not provide a photographed map of individual Oort Cloud objects.
Distance
The planetary system occupies only the centre
At Oort Cloud distances, the familiar orbits of the planets collapse into a tiny central structure. A literal shared scale would make both navigation and comparison unusable, so Explore compresses this region while keeping the scientific range explicit on the page.
Representation
An inferred shell, not a luminous bubble
The visible cloud is a restrained diagram made of sparse inner, outer and anchor populations. Brightness, opacity and particle size are interface choices; the actual bodies would be small, dark and extraordinarily far apart.
Representation notes
What Explore is showing
Explore uses a compressed shell whose rendered radius is chosen for framing and performance. The page preserves the much larger scientific distance range and labels the population as inferred.
Inner, outer and anchor strata make the shell readable only when selected. Their opacity does not represent measured density or emitted light.
Provenance