The Solar System. Objectives 1.Describe how the solar system formed. 2.Summarize the main...

The Solar System

Objectives

1. Describe how the solar system formed.

2. Summarize the main characteristics of each of the 8 planets as well as other objects in our solar system.

3. Explain the laws that govern the motion of the planets (Kepler’s Laws).

Formation of the Solar System

• 4.6 billion years ago, the same nebula that formed the sun also lead to the formation of the planets.

• This material is what’s left over after an ancient star went supernova.

Formation of the Solar System• Gravity pulled this nebular material together into

a rotating flat disc.• Debris collects into ‘planetesimal’ bodies.

Kepler Space Telescope

• Launched in March 2009, the Kepler Space Telescope is searching for planets in orbit of other stars.

• Thanks to Kepler scientists, we now have direct evidence of many extra-solar planets.

Launch video

Our Solar System

The Sun

Facts about the Sun• Almost 1 million miles in

diameter

• Temperature: Surface = 5500 C Core = 15.7 million C

• Rotates every 25 hrs.

• Mostly hydrogen (73.5%) and helium (24.9%)

•

Mercury

Facts about Mercury• 4878 km in diameter

• Temperature: Surface = 175 C

• 1 day = 58.7 Earth days 1 year = 88.96 days

• No moons, no rings•

Venus

Facts about Venus• 12,104 km in diameter

• Temperature: Surface = 450 C

• 1 day = 243 Earth days 1 year = 224.7 days

• No moons, no rings•

Earth

Facts about Earth• 12,756 km in diameter• Temperature: Surface = 15 C• 1 day = 24 hours 1 year = 365.25 days• 1 moon, no rings•

MarsV

ideo

of M

ars

Facts about Mars• 6787 km in diameter

• Temperature: Surface = -40 C

• 1 day = 24.6 hours 1 year = 687 days

• 2 moons (Phobos & Deimos), no rings

•

More Mars Photos

Phobos Deimos

Landing of rover ‘Opportunity’

Water on Mars?

Life on Mars?

Jupiter

Facts about Jupiter• 142,796 km in diameter

• Temperature: • Cloud top = -150 C

• 1 day = 9.8 hours 1 year = 11.86 Earth years

• 63 moons, 1 faint ring•

Jupiter and Comets

Saturn

Facts about Saturn• 120,660 km in diameter

• Temperature: Surface = -185 C

• 1 day = 10.2 hours 1 year = 29.46 years

• 61 moons, >30 rings•

Saturn and the Earth

More about Saturn• Currently, the

Cassini-Huygens mission is investigating the Saturn system.

• Jan. 2005, Huygens landed on Titan.

• Cassini Landing on Titan

Uranus

Facts about Uranus• 51,118 km in diameter

• Temperature: Surface = -214 C

• 1 day = 17.9 hours 1 year = 84.1 years

• 27 moons, 13 rings•

Uranus Video

Neptune

Facts about Neptune• 48,600 km in diameter

• Temperature: Surface = -225 C

• 1 day = 19.1 hours 1 year = 164.8 years

• 13 moons, 5 rings•

Neptune Video

Why isn’t Pluto a planet??Pluto Video

Other Objects in our Solar System

• Asteroids- small rocky body orbiting the sun.

• Comets- icy body, orbiting the sun (has a visible tail).

• Dwarf Planets- small ‘planet-like’ objects orbiting the sun.

• Meteoroid- tiny rocky object in space• Meteor- a meteoroid that has entered the atmosphere• Meteorite- a meteor that has hit the ground

•

Solar System Summarized

NASA Images Set to Music