At least on Zalit they had lived in high-pressure spherical tanks which were filled with methane.

Most of it was a spherical tank.

Tavalera looked up at the Graham, hanging a hundred meters or so away from the spherical tank.

As he looked out, though, he saw two huge spherical tanks swing into view, and several spacesuited figures clambering on them.

Use of spherical tanks and stubby shape to reduce vehicle structural mass further.

The huge room, which appeared to be as large as Starhall, was dominated by a spherical tank some ten feet in diameter.

It is believed this configuration was chosen because it weighed less than a spherical tank of the same volume.

Outside the hangar, a perfectly spherical tank, a three-foot fuel cell, appeared shiny and still.

Just outside the terminal building, a row of spherical tanks marched off to a distant wall.

They then climbed, one by one, into the spherical tanks.