The Solar System

How should we categorize the objects in the Solar System?

Our Star, the Sun

Our Star, the Sun

The Sun is the Largest Object in the Solar System

• The Sun contains more than 99.85% of the total mass of the solar system

• If you put all the planets in the solar system, they would not fill up the volume of the Sun

• 110 Earths or 10 Jupiters fit across the diameter of the Sun

How big is the Sun?

Tutorial: Sun Size (pg – 63)

• Work with a partner!• Read the instructions and questions carefully.• Discuss the concepts and your answers with one

another. Take time to understand it now!!!!• Come to a consensus answer you both agree on.• If you get stuck or are not sure of your answer, ask

another group.

Debrief Tutorial: Sun Size

• The Sun is HUGE!• Any questions?

The Sun has a diameter of approximately 1.4 million kilometers. Roughly how many Earths would fit across the diameter of the

Sun?

10 100

1000

1000

0

1 milli

on

3%

80%

8%6%3%

1. 102. 1003. 10004. 10,0005. 1 million

The Sun has a diameter of approximately 1.4 million kilometers. Roughly how many Earths would fit across the diameter of the

Sun?

10 100

1000

1000

0

1 milli

on

3%

80%

8%6%3%

1. 102. 1003. 10004. 10,0005. 1 million

If you were constructing a scale model of the solar system that used a Sun that was the size of a basketball (~ 12”

diameter), which of the following lengths would most closely approximate the scaled distance between Earth and the Sun?

3 fee

t (len

gth of an o

u...

10 fe

et (h

eight

of a b...

100 f

eet (h

eight o

f an ...

300 f

eet (l

ength

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.

6%19%

69%

7%

1. 3 feet (length of an outstretched arm)2. 10 feet (height of a basketball goal)3. 100 feet (height of an 8 story building)4. 300 feet (length of a football field)

If you were constructing a scale model of the solar system that used a Sun that was the size of a basketball (~ 12”

diameter), which of the following lengths would most closely approximate the scaled distance between Earth and the Sun?

3 fee

t (len

gth of an o

u...

10 fe

et (h

eight

of a b...

100 f

eet (h

eight o

f an ...

300 f

eet (l

ength

of a f..

.

6%19%

69%

7%

1. 3 feet (length of an outstretched arm)2. 10 feet (height of a basketball goal)3. 100 feet (height of an 8 story building)4. 300 feet (length of a football field)

Comparisons among the nine planets show distinct similarities and significant

differences

How should we divide the Solar System?

How should we divide the Solar System?

How should we divide the Solar System?

How should we divide the Solar System?

Jupiter Mercury

Mercury Jupiter

Mercury Jupiter

• Which of these is Earth-like?• Which of these is Jupiter-like?• Or are they the same (both Earth-like

or Jupiter-like)?

How should we divide the Solar System?

The Inner Planets(Family Portrait)

The Outer Planets(Family Portrait)

Inner (Terrestrial) Planets• Mercury• Venus• Earth• Mars• Characteristics

– Small– Rocky– Very close to the Sun– Have few moons– Have no rings

Mercury

Photographs from Mariner

10 reveal Mercury’s lunar-like

surface

Mercury Moon

The surface of Venus is

completely hidden beneath

permanent cloud cover

The Venusian Surface

Venus is covered with gently rolling hills and numerous volcanoes

EARTH

• More on this planet later

Mars, as seen from Earth

Mars, as seen from the Hubble Space Telescope

Valles Marineris is as big as the entire United States of America

Enormous shield volcanoes

Ice caps dominate the poles during different times of the year

Olympus Mons - the largest volcano in the solar system has a base larger than the state of Arizona

Early space probes to Mars found no canals but did find some

controversial features

Surface features indicate that water once flowed on Mars

Ohio River valley on Earth

River channels on Mars

Viking I Lander Picture from 1976

1999 Picture from the Mars

Pathfinder Lander

Note the remote-control rover,

Sojourner, next to a Martian rock

Mars Water/Ice Discovered

Prather • Offerdahl • Slater

Activities Manual

The Martian meteorite found in Antarctica has not provided conclusive

evidence about life on Mars

2004 testing Opportunity Lander at JPL

2004 “Opportunity” Landing Site – and tracks

2004 “Opportunity” picture of Crater Wall

2004 “Opportunity” drilling holes in crater wall with robotic

2004 Spirit tracks back to landing site

Most asteroids orbit the Sun between Mars and Jupiter

In general, asteroids are small

Asteroid Ida and its tiny moon, Dactyl

Outer Planets

• Jupiter• Saturn• Uranus• Neptune• Pluto

• Enormous• Gaseous• Far from Sun• Separated by large

distances• Have ring systems• Have many moons

Outer (Jovian) Planets

Inner planets are vastly different than outer planets in terms of orbital distances

The Outer Planets(Family Portrait)

Jupiter is the Largest of the Gas Giant Planets

Besides being the largest planet,

Jupiter is probably best known for its

Great Red Spot - a hurricane-like

storms that has been observed ever since the invention of the

telescope.

Jupiter has four large moons and lots of small ones

Io’s surface is sculpted by volcanic activity

Europa may harbor

liquid water below its

icy surface

Ganymede is larger than Mercury

Callisto wears the scars of a huge asteroid

impact

Saturn has the most extensive ring system in the solar system

Saturn’s spectacular rings are composed of fragments of ice and ice-coated rock

Titan is Saturn’s largest moon

Titan has a thick, opaque

atmosphere rich in nitrogen,

methane and other hydrocarbons

(including ethane, acetylene, ethylene,

and propane)

Saturn and Jupiter share the same basic structure

Uranus has a hazy atmosphere with

few clouds

A system of rings and satellites revolves around Uranus

Uranus’ tilt gives it very exaggerated seasons

Uranus’ odd moon Miranda

Brilliant blue Neptune has a giant storm too

Neptune’s Rings

Neptune’s largest moon, Triton, was probably captured by Neptune’s gravity

Uranus and Neptune have similar interiors

Clyde Tombaugh discovered Pluto in 1930 by comparing photographs taken

a few days apart.

Pluto and its moon, Charon, are about the same

size

PLANET “X”!!!

• In 2005, after a search of about half of the sky and the discovery of dozens of objects almost the size of Pluto, we found 2003 UB313, the first object larger than Pluto and the largest object found in the solar system since 1848

Collisions dominated the early solar system

• dust collects together into planetesimals• planetesimals collect together into protoplanets• Protoplanets gather up left over debris and

became planets

The solar system formed from a cloud of cold gas and dust called the solar nebula about 4.6 billion

years ago

The planets formed by the accretion of planetesimals and the accumulation of gases

in the solar nebula

Which planet formed at the furthest location from the Sun where it was hot enough to boil water ?

A. MercuryB. MarsC. JupiterD. NeptuneE. None of the above

Which planet formed at the furthest location from the Sun where it was hot enough to boil water ?

A. MercuryB. MarsC. JupiterD. NeptuneE. None of the above

Tutorial: Temperature and Formation of Our Solar System – p. 57

• Work with a partner!• Read the instructions and questions carefully.• Discuss the concepts and your answers with one

another. Take time to understand it now!!!!• Come to a consensus answer you both agree on and

write complete thoughts into your LT.• If you get stuck or are not sure of your answer, ask

another group.

The standard model of solar system formation offers what explanation for the different compositions of the terrestrial and

Jovian planets?1. During the condensation, the heavier elements tended to sink nearer

the Sun and only provided enough material to build the relatively small terrestrial planets.

2. During the collapse of the gaseous nebula, most of the material tended to collect far from the Sun because of the large centrifugal forces, which provided the necessary material to build the large Jovian planets

3. The large gravitational forces of Jupiter tended to prevent plant formation in the inner solar system and eventually attracted most of the material into the region of the Jovian planets

4. The terrestrial planets were formed near the Sun where, because of the high temperatures, only heavier elements were able to condense

The standard model of solar system formation offers what explanation for the different compositions of the terrestrial and Jovian planets?

1. During the condensation, the heavier elements tended to sink nearer the Sun and only provided enough material to build the relatively small terrestrial planets.

2. During the collapse of the gaseous nebula, most of the material tended to collect far from the Sun because of the large centrifugal forces, which provided the necessary material to build the large Jovian planets

3. The large gravitational forces of Jupiter tended to prevent plant formation in the inner solar system and eventually attracted most of the material into the region of the Jovian planets

4. The terrestrial planets were formed near the Sun where, because of the high temperatures, only heavier elements were able to condense

Which planet formed closest to the Sun at temperatures near the Sun below the freezing

point of water?

1. Venus2. Earth 3. Mars4. Jupiter5. Saturn

Which planet formed closest to the Sun at temperatures near the Sun below the freezing

point of water?

Jupiter

Astronomers have discovered massive gas giant planets like Jupiter orbiting companion stars at closer than .7 AU (about distance of Venus’s orbit) Why don’t astronomers

believe that these gas giants originally formed at these locations?

1. The planets’ gravity would have been too large to form that close to the star

2. The temperature in th eearly solar nebula was too high at these distance

3. Their orbital periods are too long for them to be located that close to their companion stars

4. A young star’s solar wind would have blown the planets farther away.

Astronomers have discovered massive gas giant planets like Jupiter orbiting companion stars at closer than .7 AU (about distance of Venus’s orbit) Why don’t astronomers

believe that these gas giants originally formed at these locations?

The temperature in the early solar nebula was too high at these distance

Vagabonds of the Solar System

Comet Kohoutek and Comet West

Comets have two tails

Comets often have two tails: a thin ION tail and a curving DUST tail

ion tail

dust tailcoma

The anatomy of a comet

Comets lack tails until they enter the inner solar system. A comet’s tails always point away from the Sun, no matter

which way the comet is moving!

Anatomy of a comet

15 km long by 8 km wideComet Halley nucleus

Meteor showers occur when Earth passes through the dusty tail debris left by a passing comet. Dust particles burn up as they enter Earth’s atmosphere, like bright light shooting from a single point in the sky.