I believe the answer is Mars.
yes, mercury's thin atmosphere has methane.
Uranus contains Methane in its atmosphere which gives it a aquamarine or cyan colour.
No it is not breathable, because the planet is full of dangerous gases such as methane.
The planet Jupiter does have lots of methane in its atmosphere.
If you mean what is in its atmosphere, its methane, which is why the planet has a blueish-green tint.
Uranus and Neptune Yes, they have methane, but it's only 2 or 3 percent of their atmospheres.
The answer is Jupiter.
I would think Saturn.
Saturn is the sixth planet from the Sun. Its atmosphere is primarily hydrogen. It also contains some helium, methane, ethane and ammonia.
The planet appears to be partly covered with frozen methane gas and to have a thin atmosphere composed mostly of methane.
Neptune
No because it has methane in its atmosphere so that is why it has the bluish color.