# Outgassing · Concept

> Gas escaping from a body as it warms, which can push it and make a tail.

Source: https://mysteriesdept.com/concepts/CPT0DECW037EHK5/outgassing  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Concepts](https://mysteriesdept.com/concepts)Outgassing

Concept · astronomy · in 1 mystery

# Outgassing

Gas escaping from a body as it warms, which can push it and make a tail.

[1I/'Oumuamua](https://mysteriesdept.com/mysteries/oumuamua)

Ice in a comet turns to gas when the Sun warms it; the gas streams away and pushes the comet slightly off its gravitational path. For ʻOumuamua, outgassing of hydrogen or nitrogen ice is the leading natural account of its acceleration, and the absence of a visible coma is the objection every version of it has to answer.

## Where it comes up

**[1I/'Oumuamua](https://mysteriesdept.com/mysteries/oumuamua)**

[Sublimation of nitrogen ice from a fragment of an exo-Pluto's surface.](https://mysteriesdept.com/mysteries/oumuamua/answers/ANS0CSKC3J40JAH/sublimation-of-nitrogen-ice-from-a-fragment-of-an-exo-plutos)[Sublimation of molecular hydrogen ice from a body made largely of it.](https://mysteriesdept.com/mysteries/oumuamua/answers/ANS0CSKC2JW01ZS/sublimation-of-molecular-hydrogen-ice-from-a-body-made)[Outgassing of water or another undetected ordinary volatile from an icy body, below the limits of every…](https://mysteriesdept.com/mysteries/oumuamua/answers/ANS0CSKC0W61KZV/outgassing-of-water-or-another-undetected-ordinary-volatile)[Sublimation of a volatile ice drives the axis ratio to extreme values.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKCG0J1CWD/sublimation-of-a-volatile-ice-drives-the-axis-ratio-to)[The light curve shows no secular change in spin, which is in tension with how outgassing comets spin up.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKC2B22PP3/the-light-curve-shows-no-secular-change-in-spin-which-is-in)[No water outgassing was ever detected.](https://mysteriesdept.com/mysteries/oumuamua/evidence/EVD0CSKCA527WAC/no-water-outgassing-was-ever-detected)

## Cite it

```
Mysteries Department. (2026). Outgassing [Concept CPT0DECW037EHK5]. https://mysteriesdept.com/r/CPT0DECW037EHK5
```

Key

**CPT** 0DECW037EHK5

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Concept

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Astronomy

Related

[Non-gravitational acceleration](https://mysteriesdept.com/concepts/CPT0DECW031ZQ1N/non-gravitational-acceleration)

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[Non-gravitational acceleration](https://mysteriesdept.com/concepts/CPT0DECW031ZQ1N/non-gravitational-acceleration)

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