# An ultra-porous fractal aggregate of icy dust.

> Still possible: An ultra-porous fractal aggregate of icy dust.

Source: https://mysteriesdept.com/mysteries/oumuamua/answers/ANS0CSKCBVR4ARH/an-ultra-porous-fractal-aggregate-of-icy-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 ultra-porous fractal aggregate of icy dust.

An ultra-porous fractal aggregate of icy dust.

**Still possible** Answers **1** questionPublished0

## Where it stands

**Still possible** Its tests haven't settled it: one piece of evidence for, one against. It needs two reviews to be accepted.

## What it predicts

- A bulk density far below any known small body.
- Infrared behaviour unlike a solid body.

## What would rule it out

- A measured bulk density or thermal inertia of an analogue inconsistent with an aggregate.

## Evidence 1 for · 1 against

[Explains the push by radiation pressure and an apparent spin change by YORP.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKCC3J488A/explains-the-push-by-radiation-pressure-and-an-apparent-spin)

Speculative

FOR

[Formation and survival of an aggregate this size are not demonstrated.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKCCBC5W0Y/formation-and-survival-of-an-aggregate-this-size-are-not)

Suggestive

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 ultra-porous fractal aggregate of icy dust. [Answer ANS0CSKCBVR4ARH]. https://mysteriesdept.com/r/ANS0CSKCBVR4ARH
```

Key

**ANS** 0CSKCBVR4ARH

Kind

Answer · hypothesis

Origin

Published

Version

1

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