Large mobile cities created by humans to live after Earth atmosphere became too polluted to live.

This burn-off throws large amounts of carbon dioxide into the Earth atmosphere.

They used it, however, at three Earth atmospheres pressure and included trace compounds such as hydrogen cyanide.

Air pressure, less than half a standard Earth atmosphere.

When the characters did go off of the ship, the worlds all had Earth atmosphere and colors.

This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.

However, it has since been demonstrated that the conditions used for the experiment may not have been an accurate representation of the early Earth atmosphere.

The surface pressure was down from a stupefying ninety Earth atmospheres to less than twenty.

"Level her off," Dom ordered, when the outside pressure was one Earth atmosphere.

It fragmented outward, driven by the pressure of the Earth atmosphere.