# An ordinary comet-like planetesimal of water ice and dust under an insulating organic crust (with or without…

> Most likely: An ordinary comet-like planetesimal of water ice and dust under an insulating organic crust (with or without cosmic-ray hydrogen trapped in…

Source: https://mysteriesdept.com/mysteries/oumuamua/answers/ANS0CSKC95T4XTH/an-ordinary-comet-like-planetesimal-of-water-ice-and-dust  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Questions](https://mysteriesdept.com/questions)[1I/'Oumuamua](https://mysteriesdept.com/mysteries/oumuamua)[What was 'Oumuamua made of?](https://mysteriesdept.com/mysteries/oumuamua/questions/QST0CSKBZN458NQ/what-was-oumuamua-made-of)Answer

Answer · 1I/'Oumuamua

# An ordinary comet-like planetesimal of water ice and dust under an insulating organic crust (with or without…

An ordinary comet-like planetesimal of water ice and dust under an insulating organic crust (with or without cosmic-ray hydrogen trapped in the ice).

**Most likely** Answers **1** questionPublished0

## Where it stands

**Most likely** Its tests partly supported it: three pieces of evidence for, one against. It needs two reviews to be accepted.

## What it predicts

- The surface is a red irradiated organic mantle.
- Interstellar objects as a class are mostly comet-like, as 2I and 3I were.

## What would rule it out

- A composition-specific gas detected from a future analogue that is not water, CO, CO2 or hydrogen from water.

## Evidence 3 for · 1 against

[2I/Borisov and 3I/ATLAS were both ordinary comets in composition, if unusually rich in CO or CO2.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKC9X84DNV/2i-borisov-and-3i-atlas-were-both-ordinary-comets-in)

Supported

FOR

[The radiolytic-hydrogen model makes an ordinary water-ice body fit the acceleration.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKC9NE57F6/the-radiolytic-hydrogen-model-makes-an-ordinary-water-ice)

Suggestive

FOR

[The red featureless spectrum fits an organic-rich mantle half a metre thick that could have kept interior ice…](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKC9DM58PB/the-red-featureless-spectrum-fits-an-organic-rich-mantle)

Supported

FOR

[No water outgassing was ever detected.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKCA527WAC/no-water-outgassing-was-ever-detected)

Established

AGAINST

## The questions it answers

[What was 'Oumuamua made of?](https://mysteriesdept.com/mysteries/oumuamua/questions/QST0CSKBZN458NQ/what-was-oumuamua-made-of)

Most likelyAn ordinary comet-like planetesimal of water ice and dust under an insulating organic crust (with or without…

## Cite it

```
Mysteries Department. (2026). An ordinary comet-like planetesimal of water ice and dust under an insulating organic crust (with or without… [Answer ANS0CSKC95T4XTH]. https://mysteriesdept.com/r/ANS0CSKC95T4XTH
```

Key

**ANS** 0CSKC95T4XTH

Kind

Answer · hypothesis

Origin

Published

Version

1

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