David Rothery on Volcanism in the Solar System
David Rothery is Professor of Planetary Geosciences at The Open University. He studies volcanism here on Earth and throughout the Solar System. He is an accomplished educator and has written popular books on geology, volcanism, and moons; authored university courses; and led numerous field trips. The photo shows him leading a field trip in Hawaii.
Photo: Oliver Strimpel
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Podcast Illustrations
Magellan radar image of a 300 x 230 km region of Venus showing lava flows and volcanos. The dark flows probably represent smooth lava flows similar to 'pahoehoe' flows, which have a smooth or ropey surface on Earth, while the brighter lava flows are rougher flows similar to 'aa' flows, which have a rough, clinkery texture on Earth. The rougher flows are brighter because the rough surface returns more energy to the radar than the smooth flows.
Courtesy of NASA/JPL
A view of the Moon looking south across Oceanus Procellarum, with an artist’s impression of how the edges of the dark volcanic plains called maria may have looked while active. The evidence for this comes from gravity studies, which indicate that the structures at the maria edges are ancient, solidified, lava-flooded rifts that are now buried beneath the surface of the maria on the near side of the Moon.
Courtesy of NASA/Colorado School of Mines/MIT/JPL/GSFC
Eruption from a volcano on Jupiter’s moon Io imaged by New Horizons during its Jupiter fly-by en route to Pluto. The plume is 330 km high, though only its uppermost half is visible in the image as its source lies over the moon's limb on its far side. The images were captured over the course of eight minutes. This is an example of silicate volcanism, similar to that occurring on Earth except that the explosion is taking place into a vacuum.
Courtesy of NASA
Diagram illustrating the cryovolcanic processes thought to be happening on Enceladus, an icy moon of Saturn. Cracks in the ice shell enveloping the moon allow water and other compounds to escape into space. The lack of confining pressure causes them to vaporize instantly.
Courtesy of NASA/JPL
Exaggerated color image from MESSENGER centered on Nathair Facula, the diffuse-edged yellow spot about 260 km in diameter that dominates this view. It is interpreted as the explosive deposit from a series of eruptions from the compound volcanic vent labeled in the image. When active, it would have resembled a present-day explosive eruption on Io. Also appearing in the image is Copland, a lava-flooded impact crater 208 km in diameter.
Courtesy of NASA/JHU APL/Carnegie Institute Washington
David Rothery with a full-size engineering model of the X-ray spectrometer assembled at Leicester University that is aboard the BepiColombo spacecraft. The spectrometer will analyze the surface of Mercury by collecting fluorescent X-rays emitted by the surface rocks after stimulation by high-energy solar X-rays. On the right with the square aperture is a collimator (MIXS-C) that collects X-rays efficiently over a broad range of energies with a wide field of view (~10°). On the left with the circular aperture is an X-ray telescope (MIXS-T) for high-resolution, narrow field (1° field of view) mapping of the planetary surface.
Courtesy of David Rothery
Artist’s impression of the BepiColombo Mercury Planetary Orbiter as it will look free-flying in Mercury orbit. The X-ray spectrometer telescope (MIXS-T) and collimator (MIXS-C) apertures are labeled.
Courtesy of ESA
Cryovolcanic landscape on Miranda, an icy moon of Uranus about 500 km in diameter. These cryovolcanic lava flows are well over a billion years old. If David Rothery could pick the next space mission, he would go there to see this landscape in greater detail, as well as the as-yet-unseen terrain that was in darkness when Voyager-2 flew past in 1986.
Courtesy of JPL