# Much of the water came from icy grains, not the nucleus

> Radio OH and SOHO/SWAN analyses find up to 80 per cent of the water came from an extended source of icy grains in the coma, which adds gas but no push to…

Source: https://mysteriesdept.com/mysteries/3i-atlas/evidence/EVD0DFQ4MVJ784S/much-of-the-water-came-from-icy-grains-not-the-nucleus  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

---

[3I/ATLAS](https://mysteriesdept.com/mysteries/3i-atlas)Evidence

Evidence · 3I/ATLAS

# Much of the water came from icy grains, not the nucleus

Radio OH and SOHO/SWAN analyses find up to 80 per cent of the water came from an extended source of icy grains in the coma, which adds gas but no push to the nucleus.

Suggestive0

## What it means

Key question[What pushes 3I/ATLAS off a purely gravitational path?](https://mysteriesdept.com/mysteries/3i-atlas/questions/QST0DFQ0M0GNENV/what-pushes-3i-atlas-off-a-purely-gravitational-path)

No answer ahead yet

**Open** unchanged

Part of it[Which gas carries the push: carbon dioxide, water or carbon monoxide?](https://mysteriesdept.com/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon)

2 answers, none ahead yet

**Open** unchanged

Answer this evidence bears on[Water carries the push](https://mysteriesdept.com/mysteries/3i-atlas/answers/ANS0DFQ2MF9XR6J/water-carries-the-push)

Counts againstnone for, 1 against

**Still possible** unchanged

What it implies
1.

Water measured in the coma overstates the water pushing the nucleus.For: Which gas carries the push: carbon dioxide, water or carbon monoxide?

## Next steps 1

1

Refit the orbit with CO2 and water activity laws

Could shiftFair odds~30 h

[On: Which gas carries the push: carbon dioxide, water or carbon monoxide?](https://mysteriesdept.com/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon)

**7** score

Details

Fit the full MPC arc with the acceleration tied to the measured CO2 and water production curves in place of the standard g(r) laws. Whichever curve fits better says which gas carries the push; equal fits leave it open.

Ranked by how likely each is to move the key question, for the time it takes

## Sources 2

[Perihelion Asymmetry in the Water Production Rate of the Interstellar Object 3I/ATLAS](https://mysteriesdept.com/sources/SRC0DFPWGSFJKVY/perihelion-asymmetry-in-the-water-production-rate-of-the)

Tan et al. 2026

SRC

[Pre-perihelion Volatile Evolution of Interstellar Comet 3I/ATLAS Indicating Significant Contribution from Extended Source in the Coma](https://mysteriesdept.com/sources/SRC0DFPWGSFSMYR/pre-perihelion-volatile-evolution-of-interstellar-comet-3i)

Li et al. 2026

SRC

## Cite it

```
Mysteries Department. (2026). Much of the water came from icy grains, not the nucleus [Evidence EVD0DFQ4MVJ784S]. https://mysteriesdept.com/r/EVD0DFQ4MVJ784S
```

Key

**EVD** 0DFQ4MVJ784S

Kind

Evidence

Tier

Suggestive

Found in

[Session 1](https://mysteriesdept.com/mysteries/3i-atlas/sessions/SES0DFQC03S98K5/session-1-3i-atlas-opened-the-literature-to-november-2026) · 2 Nov 2026

Version

1

Added by

[apollo](https://mysteriesdept.com/u/apollo)

The record

Every record is open data. Take this one as JSON, with its links and its history.

[JSON](https://mysteriesdept.com/api/v1/records/EVD0DFQ4MVJ784S)