Mysteries Department
Sign inRequest access
0

Is 'Oumuamua typical of interstellar objects, or a rare kind?

Asked 26 Oct 2026 by ·Part of Where did 'Oumuamua come from?·3 answers·0·0 following
Three answers, none aheadNone is ahead yet. See what would settle it.

Where it stands

Three answers have been proposed. None is ahead on the evidence yet. Three are still possible.

Why it matters

With three objects known, two of them ordinary comets, whether 'Oumuamua represents a common class bears on every reading that requires an unusual body⁠[1]⁠[2].

Answers 3

Evidence: 2 for, 1 against
Still possible
Evidence: 2 for
Still possible
None of these.
Not tested enough to call either way
Evidence: none yet
Still possible

History

  1. Guzik et al.: 2I/Borisov was an ordinary active comet.For: 'Oumuamua was an unusual member of a population dominated by comets like 2I and 3I.
  2. Jewitt & Seligman puts forward: 'Oumuamua was an unusual member of a population dominated by comets like 2I and 3I.
  3. Jewitt & Seligman: the detection implies a number density of about 0.1 per cubic au.For: Asteroid-like, inactive interstellar objects are common, and 'Oumuamua is one of many.
  4. Hopkins et al.: 3I's age and composition make a common origin with 1I or 2I very unlikely, so three objects sample different…Against: 'Oumuamua was an unusual member of a population dominated by comets like 2I and 3I.
  5. Cordiner et al.: 3I/ATLAS was an active comet rich in CO2.For: 'Oumuamua was an unusual member of a population dominated by comets like 2I and 3I.
  6. Albornoz-Montenegro & Fuentes puts forward: asteroid-like, inactive interstellar objects are common, and 'Oumuamua is one of many.
  7. Albornoz-Montenegro & Fuentes: size-distribution modelling with 1I and 3I suggests asteroid-like bodies are produced more often than comets.For: Asteroid-like, inactive interstellar objects are common, and 'Oumuamua is one of many.
  8. Asked on this site
Add evidence
1What it bears on2What you found3Where it comes from
Which answer?
Does it count for or against it?
In a sentence, what did you find?
What you found optional
Where it comes from optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.
Propose an answer
Your answer, in a sentence
What would rule it out? optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.
Ask a sub-question
Your question
Why it would help optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.
Add a source
The source
What it shows about this question optional
Two reviewers check it before it counts, one of whom backs a different answer. You'll hear back by email: accepted, needs changes, or a duplicate.

Discussion 0

Add to the discussion