# Methane was present at the reported levels in 2003–2006 and has since declined or become rarer.

> Disputed: Methane was present at the reported levels in 2003–2006 and has since declined or become rarer.

Source: https://mysteriesdept.com/mysteries/mars-methane/answers/ANS0D7EY4HM4YRK/methane-was-present-at-the-reported-levels-in-20032006-and  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Questions](https://mysteriesdept.com/questions)[Mars methane puzzle](https://mysteriesdept.com/mysteries/mars-methane)[Were the remote detections of 2003–2006 real?](https://mysteriesdept.com/mysteries/mars-methane/questions/QST0D7EXXPW2F4B/were-the-remote-detections-of-20032006-real)Answer

Answer · Mars methane puzzle

# Methane was present at the reported levels in 2003–2006 and has since declined or become rarer.

Methane was present at the reported levels in 2003–2006 and has since declined or become rarer.

**Disputed** Answers **1** questionPublished0

## Where it stands

**Disputed** Two pieces of evidence for, none against. It needs two reviews to be accepted.

## What it predicts

- Re-analysis of the archived PFS spectra with modern methods recovers the detections.

## What would rule it out

- Re-analysis showing the features are below significance or due to telluric or solar lines.

## Evidence 2 for · none against

[Ground-based spectra showed plumes, the largest about 19,000 tonnes.](https://mysteriesdept.com/mysteries/mars-methane/evidence/EVD0D7EY5184TSS/ground-based-spectra-showed-plumes-the-largest-about-19-000)

Suggestive

FOR

[PFS reported a global average of 10 ± 5 ppbv, varying from 0 to 30 ppbv.](https://mysteriesdept.com/mysteries/mars-methane/evidence/EVD0D7EY4SE56C4/pfs-reported-a-global-average-of-10-5-ppbv-varying-from-0-to)

Suggestive

FOR

## The questions it answers

[Were the remote detections of 2003–2006 real?](https://mysteriesdept.com/mysteries/mars-methane/questions/QST0D7EXXPW2F4B/were-the-remote-detections-of-20032006-real)

Part of [If the methane is real, where does it come from?](https://mysteriesdept.com/mysteries/mars-methane/questions/QST0D7EXXF26RFA/if-the-methane-is-real-where-does-it-come-from)

Most likelyThe early remote detections were not secure

## Cite it

```
Mysteries Department. (2026). Methane was present at the reported levels in 2003–2006 and has since declined or become rarer. [Answer ANS0D7EY4HM4YRK]. https://mysteriesdept.com/r/ANS0D7EY4HM4YRK
```

Key

**ANS** 0D7EY4HM4YRK

Kind

Answer · hypothesis

Origin

Published

Version

1

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