It could not be water ice, which cannot exist in the extremely hot, dry conditions of the Venusian surface.

The Venusian surface at that point was little more than ashy sand.

Much of the Venusian surface appears to have been shaped by volcanic activity.

Radar observations in the 1970s revealed details of the Venusian surface for the first time.

The mission of this spacecraft was to land on the Venusian surface.

In particular, the pressure readings by the capsule were much too low for the Venusian surface.

The initial project is expected to give scientists images of 90 percent of the Venusian surface.

Researchers offered two theories for how the Venusian surface has changed since the planet was formed.

This also supported the theory that the Venusian surface was extremely hot or the atmosphere optically thick.

"It's at least eight hundred degrees Fahrenheit on the Venusian surface."