The Jovian Planets Chapter 7 Topics Jupter, Saturn,

The Jovian Planets Chapter 7 Topics

Jupter, Saturn, Uranus, Neptune How do we know? Why do we care? What is common about the outer planets? What is peculiar to each of these planets? Jovian planets (Jupiter-like) Size

radius is about 1/10 of the radius of the Sun Terrestrial Distance from the Sun Jovian Terrestrial Size

Jovian small--1/100 radius large --1/10 radius of the Sun of the Sun orbit at 0.4

to 1.5 orbit at 5 to 30 n o i

t a c Lo AU AU s few n o o

M none s g n i R n o i

t i s o p Com rocks and metals many (# growing) all have rings gasses and ice

Composition 0.71 to 1.67 g/cm3 So what are they made of? mostly gasses (hydrogen, helium) and ice Jupiter largest planet Great Red Spot studied by Pioneer,

Voyager 1 & 2, Galileo spacecraft liquid interior (very high pressure and temperature) 16 moons (4 largest are the Galilean moons) Io Active volcanoes

Europa subsurface ocean cracked ice Ganymeade lots of faults strong magnetic field Callisto old surface (meaning

that its not undergoing lots of change except for impact craters) Saturn Large, thin rings Rings are held together by the gravitational attraction of shepharding satellites

Major Gaps: The Cassini and Enke divisions Titan larger than Mercury has an atmosphere probably has oceans of methane Uranus

discovered in 1781 shows no cloud banding axis of rotation is only tilted 8 degrees from the ecliptic 84 year orbital period rings originally discovered during occultation of a star young rings (whats the

source of dust?) Neptune noted by Galileo the exact path of Uranus could not be explained by the gravitational pulls of the Sun, and the other planets. What does this mean?

discovered in 1846 164 year orbital period strong magnetic field Triton density 2.1 g/cm3 atmosphere (nitrogen) impact craters due to comets ice made of water

active ice volcanoes retrograde orbit (its going the wrong way) probably captured by Neptune Extrasolar planets How many planets have we discovered besides those in our solar system? Im starting to lose count, but its now over 100.

Planets are even found in binary star systems. We analyze the wobble in a star by studying the Doppler shift in its spectrum and determine the approximate masses and distances of the orbiting planets. How do we know? How do we know that the outer planets are mostly gas and mostly made up of hydrogen and helium? How do we know that the atmosphere of a planet has

methane? How do we know the period of rotation of the outer planets? (Note: we use a different technique of measuring rotational period of the terrestrial planets.) How do we know that a moons surface is ice? How do we know the size of matter within the rings? How do we know that a moon has an old surface and that the moon has little geologic activity?