Astronomy A BEGINNER’S GUIDE TO THE UNIVERSE EIGHTH EDITION CHAPTER The Jovian Planets Lecture Presentation © 2017 Pearson Education, Inc Chapter The Jovian Planets © 2017 Pearson Education, Inc Units of Chapter • • • • • • • Observations of Jupiter and Saturn The Discoveries of Uranus and Neptune Bulk Properties of the Jovian Planets Jupiter’s Atmosphere Atmospheres of the Outer Jovian Worlds Jovian Interiors Summary of Chapter © 2017 Pearson Education, Inc 7.1 Observations of Jupiter and Saturn • • Jupiter can be imaged well from Earth, even with a small telescope Here: Jupiter with its Galilean moons © 2017 Pearson Education, Inc 7.1 Observations of Jupiter and Saturn • True-color image of Jupiter © 2017 Pearson Education, Inc 7.1 Observations of Jupiter and Saturn • Natural-color image of Saturn © 2017 Pearson Education, Inc 7.1 Observations of Jupiter and Saturn • Cassini image of Jupiter, true color © 2017 Pearson Education, Inc 7.2 The Discoveries of Uranus and Neptune • • Uranus, in natural color Note the absence of features © 2017 Pearson Education, Inc 7.2 The Discoveries of Uranus and Neptune • Neptune in natural color © 2017 Pearson Education, Inc 7.3 Bulk Properties of the Jovian Planets • The Jovian planets are large and much less dense than the terrestrial planets; Saturn is less dense than water! © 2017 Pearson Education, Inc 7.4 Jupiter’s Atmosphere • Hubble Space Telescope (HST) observations of the Great Red Spot: Merging spots are seen in the top sequence Lower sequence shows the shrinking Great Red Spot between 1995 and 2014 © 2017 Pearson Education, Inc 7.5 Atmospheres of the Outer Jovian Worlds • The atmosphere of Saturn is similar to that of Jupiter, except that Saturn is somewhat colder, its atmosphere is thicker, and its bands are fainter © 2017 Pearson Education, Inc 7.5 Atmospheres of the Outer Jovian Worlds • Saturn’s atmosphere is similar to Jupiter’s, except pressure is lower • • It has three cloud layers Cloud layers are thicker than Jupiter’s; we see only the top layer © 2017 Pearson Education, Inc 7.5 Atmospheres of the Outer Jovian Worlds • Saturn also has large storms This 2011 storm generated its own band, as seen in this sequence of images from Cassini © 2017 Pearson Education, Inc 7.5 Atmospheres of the Outer Jovian Worlds • This storm was observed by the Cassini spacecraft in 2011 in visible light • The right-hand image shows an infrared image taken after the band had faded in visible light © 2017 Pearson Education, Inc 7.5 The Atmospheres of the Outer Jovian Worlds • Saturn, like Earth and Venus, has enormous polar vortices that resemble huge storm systems The southern vortex is shown in the top image, northern vortex on the bottom © 2017 Pearson Education, Inc 7.5 The Atmospheres of the Outer Jovian Worlds • Rotation of Uranus can be measured by watching storms © 2017 Pearson Education, Inc 7.5 The Atmospheres of the Outer Jovian Worlds • Neptune has storm systems similar to those on Jupiter, but fewer The large storm system at the top has disappeared in recent years © 2017 Pearson Education, Inc 7.6 Jovian Interiors • No direct information is available about Jupiter’s interior, but its main components, hydrogen and helium, are quite well understood The central portion is thought to be a rocky core © 2017 Pearson Education, Inc 7.6 Jovian Interiors • Interior structure of Uranus and Neptune, compared to that of Jupiter and Saturn © 2017 Pearson Education, Inc 7.6 Jovian Interiors • Jupiter’s magnetosphere: – Intrinsic field strength is 20,000 times that of Earth – Magnetosphere can extend beyond the orbit of Saturn © 2017 Pearson Education, Inc 7.6 Jovian Interiors • Aurorae are seen on Jupiter and have the same cause as those on Earth—the interaction of solar wind particles with the magnetosphere © 2017 Pearson Education, Inc 7.6 Jovian Interiors • Uranus and Neptune both have substantial magnetic fields, but at a large angle to their rotation axes – The rectangle within each planet shows a bar magnet that would produce a similar field Note that both Uranus’s and Neptune’s are significantly off center © 2017 Pearson Education, Inc Summary of Chapter • Jupiter and Saturn were known to the ancients; Uranus was discovered by chance, and Neptune was predicted from anomalies in the orbit of Uranus • • Jovian planets are large but not dense; they are fluid and display differential rotation Cloud layers have light zones and dark bands; wind pattern, called zonal flow, is stable © 2017 Pearson Education, Inc Summary of Chapter 7, cont • Storms appear with regularity; the Great Red Spot of Jupiter has lasted for hundreds of years (that we know of) • • Due to conductive interiors and rapid rotation, Jovian planets have large magnetic fields Jupiter, Saturn, and Neptune radiate more energy than they receive from the Sun © 2017 Pearson Education, Inc ... with the magnetosphere © 2017 Pearson Education, Inc 7.6 Jovian Interiors • Uranus and Neptune both have substantial magnetic fields, but at a large angle to their rotation axes – The rectangle... beyond the orbit of Saturn © 2017 Pearson Education, Inc 7.6 Jovian Interiors • Aurorae are seen on Jupiter and have the same cause as those on Earth the interaction of solar wind particles with the. .. Jupiter and Saturn were known to the ancients; Uranus was discovered by chance, and Neptune was predicted from anomalies in the orbit of Uranus • • Jovian planets are large but not dense; they are