formation of the Solar System. - University of Virginia · 1 The Jovian Planets Huge worlds,...
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1 The Jovian Planets ● Huge worlds, heavily mantled in gas at the time of the formation of the Solar System.
Transcript of formation of the Solar System. - University of Virginia · 1 The Jovian Planets Huge worlds,...
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The Jovian Planets● Huge worlds, heavily mantled in gas at the time of the
formation of the Solar System.
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The Galilean Satellites● Jupiter has four planetary-sized moons first seen by Galileo
and easily visible in binoculars.
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The Galilean Satellites● Jupiter has four planetary-sized moons first seen by Galileo
and easily visible in binoculars.
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Io and Geological Activity● Io, being similar in size to the Earth's Moon, might be
expected to be a geologically dead world.
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Io and Geological Activity● It turns out to be the most volcanically active world in the
Solar System.
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Io and Geological Activity● It turns out to be the
most volcanically active world in the Solar System.
– No impact craters!
– Coloration from Sulfur and sulfur compounds.
● Density = 3.0 g/cm3
– mostly rock
– formed in a “warm location”?
– ices baked away?
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Io's “Atmosphere”● The volcanic activity produces a continuously escaping
tenuous atmosphere of sulfur and sodium near Io, and a “torus” of this material around Jupiter.
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Heating Io Internally – Tidal Stretching● Io has an elliptical orbit due to tugs from the other large
Galilean satellites.● The solid body of Io experiences significant, regular tidal
distortion as a result (the orbit takes just under 2 days)
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Heating Io Internally – Tidal Stretching● The tidal stretching heats the interior of Io significantly, so
much so that volcanism is rampant.
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Europa and Tidal Heating● Europa is the next Galilean satellite out from Jupiter● Craters are rare on Europa as well
– tidal heating is much weaker – greater distance / slower orbit
– Europa, however has an icy surface – easier to melt.
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Europa and Tidal Heating● Europa is the next Galilean satellite out from Jupiter● Craters are rare on Europa as well
– tidal heating is much weaker – greater distance / slower orbit
– Europa, however has an icy surface – easier to melt.
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Europa and Tidal Heating● Europa also has a density close to 3.0 g/cc.
– The outer layer of ice is the top of a true frozen-over “ocean” about 100 kilometers deep.
– Weak tidal heating combined with radioactive decay keep Europa warm enough keep the ocean liquid below a few kilometers of icy crust.
– Liquid water in the outer solar system!!!
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Europa and Tidal Heating● Europa also has a density close to 3.0 g/cc.
– The outer layer of ice is the top of a true frozen-over “ocean” about 100 kilometers deep.
– Weak tidal heating combined with radioactive decay keep Europa warm enough keep the ocean liquid below a few kilometers of icy crust.
– Liquid water in the outer solar system!!!
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Europa as an Abode for Life● Europa's ocean is likely habitable if
life formed there.● Interestingly, it is now thought that
life on Earth may have originated near submerged volcanic vents.
● The most primitive life forms on Earth thrive in extreme environments – e.g. boiling water.
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Europa as an Abode for Life● Europa's ocean is likely habitable if
life formed there.● Interestingly, it is now thought that
life on Earth may have originated near submerged volcanic vents.
● The most primitive life forms on Earth thrive in extreme environments – e.g. boiling water.
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Composition of the Jovian Planets● Jupiter and Saturn attracted so much gas gravitationally
during formation that the have a composition that largely matches the Sun
– Mostly hydrogen, some helium, and a a tiny fraction of the other elements.
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Composition of the Jovian Planets● Jupiter and Saturn attracted so much gas gravitationally
during formation that the have a composition that largely matches the Sun
– Mostly hydrogen, some helium, and a a tiny fraction of the other elements.
- Uranus and Neptune are also dominate by Hydrogen and Helium, but not to the degree that Jupiter and Saturn are.
- The significant portion of their mass likely made up by water leads to Uranus and Neptune being called “ice giants”
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The Galilean Satellites● Jupiter has four planetary-sized moons first seen by Galileo
and easily visible in binoculars.
