There are some specialized things they will learn at the graduate level. Students will need to learn how to make code reliable and robust. Our list includes a mix of favorites, high-impact stories and some of our most-read research coverage from a tumultuous year. Skip to content. Becoming part of Stanford's new school focused on climate and sustainability in Fall Venus mission: Is Earth's twin still geologically active? Stanford Earth Matters Dynamic Earth ,.
Planetary Science. Clock June 29, Know your planet. Subscribe Stanford Earth Matters Magazine. The four major geological processes are impact cratering, volcanism, tectonics, and erosion. Earth has experienced many impacts, but most craters have been erased by other processes. We owe the existence of our atmosphere and oceans to volcanic outgassing. Ice, water, and wind drive rampant erosion on our planet.
Both the Moon and Mercury had some volcanism and tectonics when they were young. This means that they are continuing to lose heat. While their surfaces show evidence of recent deformation — tectonism — neither planet has plate tectonic activity because neither planet has a surface divided into plates.
Mars is a smaller planet than Earth; it has cooled more, much like a small glass of hot water would cool faster than a large glass of hot water. The outermost layer of Mars is thick, thick enough to support the tallest volcano in the solar system.
Much of the tectonic activity on Mars is believed to result from convection in its interior. However, the convection appears to be restricted to a few locations. Hot material may be rising from the interior toward the surface in these locations, causing the surface to bulge, stretch, and crack. The largest of these areas is the Tharsis Bulge. Valles Marineris is a large rift, where the surface has split apart in one of these stretched regions. Venus also shows evidence of tectonic activity, where the surface has been, in some locations, stretched and broken, and in other regions, crumpled.
Scientists are debating the type of deformation that may be occurring in Venus' interior and how it may relate to the features observed on this planet's surface. Mercury and the Moon are no longer tectonically active. The Moon is believed to have been inactive essentially for the last 3 billion years; Mercury has been inactive since about 3.
However, there are hints of past tectonism. Both bodies have faults where the surface has been broken and pushed on top of itself by compressive forces. In the case of Mercury, the entire planet appears to be covered with a network of these ridges, some over kilometers miles long, suggesting that Mercury contracted slightly as it cooled. Mercury's surface showing numerous impact craters and a ridge — Santa Maria Rupes — running from the bottom middle of the image toward the upper left.
The ridge marks a fault created by compressive forces. The image is about kilometers miles across. She specializes in writing about astronomy, geology and the environment. Credit: Nick Higgins. Already a subscriber? Sign in. Thanks for reading Scientific American.
Create your free account or Sign in to continue. See Subscription Options. Go Paperless with Digital. Sliding Plates The latest study seems to contradict some previous investigations of whether or not exoplanets might shake like Earth. Get smart. Sign up for our email newsletter. Sign Up. Support science journalism. Knowledge awaits.
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