Jupiter Astronomy 311 Professor Lee Carkner Lecture 17

Jupiter’s Great Red Spot is best described as, An impact feature An eruption of water ice A hurricane-like storm A large cloud that absorbs red light The shadow of the moon Io

Which best describes the surface of the typical gas giant moon? Rocky Covered with volcanoes Enveloped by a thick atmosphere Smooth with few craters Icy

Jupiter -- King of the Gods Jupiter is also “King of the Planets” due to its size

Viewing Jupiter from Earth Is very bright from Earth In opposition every 13 months Can clearly see cloud patterns, Great Red Spot and 4 largest moons even with small telescope

Jupiter Facts Size: Orbit: Description: large, gaseous, many large satellites

Viewing Jupiter from Space Much information comes from Voyager 1 and 2 (reached Jupiter in 1979) HST can make long term observations Unlike Voyager, it observed for a long time (8 years)

Galileo’s Atmosphere Probe

Galileo Atmosphere Probe Launched from the Galileo spacecraft on Dec 7, 1995 Lasted for 1 hour and got down to 130 km below the tops of the clouds before the high temperature and pressure killed the electronics

Shoemaker-Levy 9 Discovered in 1993 Swung back around and hit Jupiter in 1994 Spectra of impacts reveals composition of deeper layers of atmosphere

Jupiter’s Atmosphere The belts are produced by convection The interior of Jupiter is hotter than the exterior Jupiter’s rotation shapes the regions of rising and falling material into belts and zones

Belts in Jupiter’s Atmosphere

Jupiter’s Rotation Jupiter has a rotation period of about 10 hours Jupiter also has differential rotation this is because Jupiter is not a solid body

Structure of Jupiter’s Atmosphere Infrared, radio and Galileo probe observations reveal 3 cloud layers Ammonium hydrosulfide (NH4SH) The color of the layers depends on depth White -- middle layer Not all layers are found in all regions

Structure of Jupiter’s Atmosphere

Spots and Ovals They are rapidly rotating cloud features (storms) Some are very long lived Some spots are white or brown Brown ovals may be holes to the deeper, hotter, inner atmosphere

Interlude Gravity Every object in the solar system pulls on every other due to gravity This can cause perturbations in orbits We can calculate the effects of gravity using Newton’s equation F=GMm/D2 We can use a modified version of this equation which shows the relative force a planet exerts: F=M/D2

Jupiter’s Interior Small core of rock and ice (about the size of the Earth) Liquid metallic hydrogen outer core (40-50,000 km thick) Hydrogen gas layer 10-20,000 km thick

The Interior of Jupiter

Rings Jupiter’s rings were discovered by Voyager May be formed from material chipped off of 4 small inner moons by impacts

Diagram of Jupiter’s Rings and Inner Moons

Jupiter’s Moons Jupiter has a planetary system of its own Jupiter has 4 of the 7 large moons of the solar system

Jupiter’s Magnetosphere

Jupiter’s Magnetosphere The magnetic field forms a magnetosphere about 200 times larger than Jupiter itself The magnetosphere deflects the solar wind to form a shock wave Also contains: a hot, thin, rapidly changing plasma rapidly moving changed particles

Next Time Chapter 12.1-12.4

Summary Jupiter is the largest planet Its strong gravity influence the motions of the rest of the solar system Rotates rapidly and differentially Explored by Voyager, HST, Galileo, and a comet impact

Summary: Atmosphere Explored by telescopes, Galileo probe and comet impact Clouds are composed of ammonia and sulfur compounds Clouds form bands of material moving in opposite directions Spots and ovals are storms which can occur at different altitudes and can be long lived Heat from Jupiter’s interior and rotation drives motions

Summary: Jupiter From the Outside In Satellites: out to ~24 million km Magnetosphere: out to ~15 million km Rings: out to ~200,000 km Atmosphere: out to ~70,000 km Liquid metallic hydrogen: out to ~50,000 km Rock/Ice core: out to ~20,000 km