Jovian Planets

Solar System Part 2

Jovian Planets

Overview:In this chapter we will look at the large jovian planets

and some of the stuff left from the formation of the solar system.

Objectives: 1. To know the characteristics that distinguish the

jovian planets, Jupiter, Saturn, Neptune and Uranus.2. To examine what is known of the final planet called

Pluto.3. To examine the asteroid belt.4. To explain comets and their origins.

Jovian Planets

• I. Jupiter• A. Orbit– 1. Jupiter is the closest of the jovian planets, with

an orbit that takes it about 5 astronomical units from the sun.

– 2. This gives the planet a year equivalent to 11.9 Earth years.

Jovian Planets

http://science.discovery.com/video-topics/space-videos/space-school-jupiter.htm#/space-school-jupiter.htm

• B. Size - Big, just big.– 1. Jupiter has a radius of 71,400 km.– 2. It would take about 1400 Earths to fill Jupiter.

Jovian Planets

• C. Composition– 1. Surprisingly, considering the size, its' density is

only ~1 g/cm3 compared with Earth's ~5 g/cm3 .– 2. Jupiter is primarily hydrogen (86%) and helium

(13.8%).– 3. The rest is methane, ammonia, and water

found mostly in the high atmosphere clouds.

Jovian Planets

• D. Rotation– 1. Differential Rotation - Since Jupiter has no

solid surface the planet is free to rotate at different rates at the equator and the pole.

– 2. Near the equator Jupiter rotates once every 9 hours and 56 minutes making it the fastest rotational body in the solar system.

Jovian Planets

– 3. At the poles the it rotates once every 9 hours and 50 minutes producing a magnetic field 20,000 times greater than the Earth's.

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Jovian Planets• E. Atmosphere• 1. Battle of the Bands• a. The light bands across

the planet are called zones and represent areas where warm material is rising in a convection current.

• b. The dark bands are called belts and are areas where cooler material is sinking in these convection currents.

Jovian Planets

– 2. Great Red Spot– a. The most prominent feature of Jupiter is the

giant circulating storm system near the equator nearly ~25,000 km in length.

– b. The spot is known to have existed since it was first reported 300 years ago.

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• F. Moons - Jupiter has at least 67 moons ranging from Leda only 15 km across to Ganymeade at 5260 km.

Jovian Planets

http://www.space.com/18400-jupiter-s-moons-some-icy-some-volcanic-and-some-larger-than-our-moon-video.html

• 1. Io– a. Io is the most geologically active object in the

solar system.– b. Due to the tidal heating caused by Jupiters gravity

Io has huge volcanoes that spew sulfur compounds, which color the surface orange.

– (loki – volcano on Jupiter)– innermost of the four Galilean moons of the planet

Jupiter and, with a diameter of 3,642 kilometres, the fourth-largest moon in the Solar System.

Jovian Planets

• 2. Europa– a. Europa is a relatively smooth moon with a

cracked ice surface.– b. It is possible that a liquid ocean warmed by

the tidal forces of Jupiter is below this cracked exterior.

– c. Many speculate this moon may be our best chance to find life.

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• G. Ring - Voyager found a faint ring of dark dust and rock about 50,000 km above the planets cloud cover

Jovian Planets

• II. Saturn• A. Orbit – 1. Saturn's orbit extends out to 9.5 astronomical

units– 2. At this distance Saturn's revolutionary period

is ~29.5 Earth years.

• B. Size - Saturn has a radius of 60,000 km.

Jovian Planets

http://science.discovery.com/video-topics/space-videos/space-school-saturn.htm#/space-school-saturn.htm

• C. Composition– 1. Saturn , like Jupiter, is mostly hydrogen (92 %)

and helium (7%)– 2. The rest is ammonia and methane.

Jovian Planets

• D. Rotation– 1. Saturn rotates every 10 hours and 14 minutes

at the equator and 10 hours and forty minutes at the pole.

– 2. This differential rotation produces a large magnetic field and a flattening of the poles.

– 3. Saturn is tilted 27 degrees, although solar heating isn't as important this far out so there aren't any noticeable seasons.

Jovian Planets

• E. Atmosphere– 1. Similar to Jupiter, Saturn has alternating

bands of gas layers forming convection currents.– 2. The cloud cover is much thicker on Saturn and

dominated by ammonia giving it a butterscotch color.

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• F. Rings - The most prominent feature of Saturn is the intricate ring system that spans ~200,000 km in diameter.

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– a. The rings consist of millions of individual chunks ranging from a few millimeters to several tens of meters in diameter.

– b. The major substance that makes up these pieces is water ice.

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• 1. Where did they come from?– a. As an orbiting body comes closer to a large source

of gravity it experiences larger and larger tidal effects.

– b. At a point called the Roch limit the internal forces holding the object together are overcome by the tidal forces ripping it apart and presto : little pieces.

Jovian Planets

• G. Moons– a. Saturn has ~18 moons ranging from Pan ~20

km across to Titan ~5150 km , near the size of the Moon.

– b. Titan is unique with a thick atmosphere of nitrogen even denser than the atmosphere of Earth.

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• c. Mimas is a medium sized moon with a proportionally huge crater called Herschel.

Jovian Planets