By Stacy Palen

A reanalysis of Magellan images has led to the hypothesis that Venus has “campi,” or blocks of rock that float on the mantle, shimmying and bumping into each other like packs of ice.

Below are some questions to ask your students based on this article.

1). Describe plate tectonics on Earth.

Answer: On Earth, a small number of very large plates float on top of the mantle, bumping into each other, sliding under or along each other’s boundaries, and creating geological features.

2). Why is liquid water required for plate tectonics?

Answer: Water lubricates the plates, permitting them to break bend and flow.

3). What happened to Venus’ liquid water?

Answer: It was lost during some kind of apocalyptic event that heated Venus to temperatures too high for liquid water to persist. This event happened about a billion years ago.

4). How is the process with campi, described in the article, different from that of plate tectonics?

Answer: Campi don’t flow past, rise over, or slide under each other. The campi are much smaller than the tectonic plates on Earth.

5). What is the evidence that this process might still be ongoing?

Answer: The observed campi are in the lava-covered lowlands, which are geologically young.

6). How will scientists explore whether this process is still actually occurring?

Answer: Several spacecraft are heading to Venus over the next few years. These spacecraft have higher-resolution radars than Magellan's and will compare the current positions of the campi with the positions observed by Magellan.