The Solar System

CHAPTER 23 | COMPARATIVE PLANETOLOGY OF JUPITER AND SATURN 513 proved mathematically that solid rings would be unstable. Saturn’ ...

PART 4 | THE SOLAR SYSTEM Encke Gap Cassini Division The C ring contains boulder-size chunks of ice, whereas most particles in t ...

F ring close up Visual-wavelength image PandoraPandora PrometheusPrometheus Because of collisions among ring particles, planetar ...

516 PART 4^ |^ THE SOLAR SYSTEM the rings arise from contamination in the ice, and some areas have unusual compositions. Th e Ca ...

CHAPTER 23 | COMPARATIVE PLANETOLOGY OF JUPITER AND SATURN 517 Saturn’s Moons Saturn has over  known satellites—far too many t ...

518 PART 4^ |^ THE SOLAR SYSTEM b Visual-wavelength image a d c Drainage channels probably were cut by flowing liquid methane. I ...

CHAPTER 23 | COMPARATIVE PLANETOLOGY OF JUPITER AND SATURN 519 The Smaller Moons In addition to Titan, Saturn has a large family ...

520 PART 4^ |^ THE SOLAR SYSTEM With a diameter of 520 km (320 mi), the small moon Enceladus isn’t much larger than Phoebe, but ...

CHAPTER 23 | COMPARATIVE PLANETOLOGY OF JUPITER AND SATURN 521 elegant dance, these moons exchange orbits and draw apart only to ...

522 PART 4^ |^ THE SOLAR SYSTEM gravitationally so that the orbits they now occupy may diff er signifi cantly from their earlier ...

CHAPTER 23 | COMPARATIVE PLANETOLOGY OF JUPITER AND SATURN 523 Summary ▶ (^) The outer planets, Jupiter, Saturn, Uranus, and Nep ...

524 PART 4^ |^ THE SOLAR SYSTEM the atmosphere, falls as rain, and drains over the surface, washing dark, organic material into ...

525 Uranus is a cloudy, Jovian world far from the sun. It is orbited by dark, rocky particles that make up narrow rings much enh ...

526 PART 4^ |^ THE SOLAR SYSTEM A good many things go around in the dark besides Santa Claus. — HERBERT HOOVER O ut in the darkn ...

CHAPTER 24 | URANUS, NEPTUNE, AND THE DWARF PLANETS 527 over two years. In the process, of course, he found many double stars th ...

528 PART 4^ |^ THE SOLAR SYSTEM Over the half-century following the discovery of Uranus, astronomers noted that Newton’s laws di ...

CHAPTER 24 | URANUS, NEPTUNE, AND THE DWARF PLANETS 529 the atmosphere contains methane, a good absorber of longer- wavelength p ...

530 PART 4^ |^ THE SOLAR SYSTEM ■ Figure 24-3 Uranus rotates on an axis that is tipped 97.9° from the perpendicular to its orbit ...

CHAPTER 24 | URANUS, NEPTUNE, AND THE DWARF PLANETS 531 Th e average density of Uranus, 1.3 g/cm^3 , tells you that the planet m ...

532 PART 4^ |^ THE SOLAR SYSTEM draws it out into a long tail extending away from the planet in the direction opposite the sun. ...