|
The atmosphere of Saturn's largest moon Titan is 98% Nitrogen with small amounts of Methane and Ethane mixed in. Earth's atmosphere is similar: 78% Nitrogen and 21% Oxygen. Earth and Titan are the only two bodies in the Solar System with substantial predominantly-Nitrogen atmospheres. Since Oxygen on Earth was all produced by lifeforms over billions of years, the atmosphere of early Earth was devoid of this gas just as Titan is today.
Return to the Astronomy Workshop