The Surface of Venus

We have a view from the Venera lander.

We have a topographic map by radar altimetry.

We have views made by the Magellan spacecraft made with radar.

• In some images we see radar shadows, from side illumination.
• Some materials are "radar bright" and some don't reflect the radar waves well.
• In a few images, radar altimetry is combined by the radar brightness images to produce perspective views, usually with vertical exageration.

Hear is a topographic map of (part of) Earth.

Here is a topographic map of Venus.

• We do see continents, but they do not seem to be pushed together like those on Earth.
• We do not see mid-ocean ridges.
• Thus it looks as though Venus does not have plate tectonics.
• On the other hand it does have tectonics (movements of the crust): we can see faults.
  • Notice the blue lines in Aphrodite Terra.

Here is what the surface looks like.
The orange color is because of Venus's atmosphere.

Venus has impact craters. Here is a a crater about 30 km in diameter.

The radar bright material is interpreted as the rocks ejected from the crater.

Here are three craters of about the same size.

Here is a crater that was broken by a fault.

Illumination is from the left.

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Venus has volcanos.
Here for your amusement are some little "pancake" volcanos:

Here is one that looks like a tick.

Note the lava flow on the northwest.

Here is a big volcano, Sapas Mons showing extensive lava flows.

Here is a perspective view of the volcano Sif Mons. (Generated by computer using radar brightness and altitude data.) Here is another view .

Comparison to Earth:

• Similar on having a hot interior and convective motions.
  • Volcanos.
  • Faults.
• But does not seem to have plate tectonics.

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