# Presentation: 004088

## Planetary Magnetic Fields

## Like many Planets in our Solar System the Earth has a Magnetic Field

## The Earth behaves as if there was a magnet in its interior.

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## The North Pole of the Earth has a “south” polarity

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## As a result a compass will always point towards the North

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## A compass is a Magnetized piece of metal that can spin. 

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- A compass is a Magnetized piece of metal that can spin.

## A compass is a Magnetized piece of metal that can spin. 

- A compass is a Magnetized piece of metal that can spin.

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- The north tip of the compass always points towards the North Pole of the Earth

- North attracts South

## A Magnetic Field also protects us from the Solar Wind 

## The Sun produces a stream of charged particles that spread throughout the solar system.

## These particles are deflected by the Earth’s Magnetic Field

## What causes a Planet’s Magnetic Field?

## The Earth’s Magnetic Field is created in the same way you make an electromagnet

## In an electromagnet the electrons move around an iron nail

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## The Earth is made of four layers

## The Crust:

- A Thin Rock Material

## The Mantle:

- A Dense and Mostly Solid Rock Material

- The Crust:
- A Thin Rock Material

- The Outer Core:
- Liquid Iron and Nickel

- The Mantle:
- A Dense and Mostly Solid Rock Material

- The Crust:
- A Thin Rock Material

- The Inner Core:
- Solid Iron and Nickel

- The Outer Core:
- Liquid Iron and Nickel

- The Mantle:
- A Dense and Mostly Solid Rock Material

- The Crust:
- A Thin Rock Material

## The Iron Core of the Earth is an Electromagnet

## The Iron Core of the Earth is an electromagnet

- The core is surrounded by liquid Iron and Nickel

## The Iron Core of the Earth is an electromagnet

- The core is surrounded by liquid Iron and Nickel

- As electrons flow around the core the magnetic field is produced

## The Iron Core of the Earth is an electromagnet

- The core is surrounded by liquid Iron and Nickel

- As electrons flow around the core the magnetic field is produced

- The Earth’s rotation makes the electrons flow at very high speeds

## A planet’s magnetic field is measured using an instrument called a Magnetometer

## Many spacecraft carry Magnetometers to measure the Magnetic Field.

- Advanced Composition Explorer

- Mars Global Surveyor

- Galileo

## Other Planets in our Solar System have Magnetic Fields

## Mercury

- Mercury has a weak magnetic field.

## Mercury

- Mercury has a weak magnetic field.

- This suggests Mercury has an iron core with liquid interior.

## Mercury

- Mercury has a weak magnetic field.

- This suggests Mercury has an iron core with liquid interior.

- The weak magnetic field could be the result of the slow rotation period.

## Venus

- Venus has a very weak magnetic field.
- (About 25,000 times weaker than Earth’s)

## Venus

- Venus appears to lack the necessary ingredients to generate a magnetic field
- (no liquid core?)

- Venus has a very weak magnetic field.
- (About 25,000 times weaker than Earth’s)

## Venus

- Venus appears to lack the necessary ingredients to generate a magnetic field
- (no liquid core?)

- Venus has a very weak magnetic field.
- (About 100,000 times weaker than Earth’s)

- Venus also has very slow rotation.

## Mars

- Mars also has a very weak magnetic field.
- (About 5,000 times weaker than Earth’s)

- The interior of Mars appears to have cooled so much that it is no longer liquid.

## Mars

- Mars also has a very weak magnetic field.
- (About 5,000 times weaker than Earth’s)

- The interior of Mars appears to have cooled so much that it is no longer liquid.

-   The volcanoes in Mars are no longer active

## Mars

- Mars also has a very weak magnetic field.
- (About 5,000 times weaker than Earth’s)

- The interior of Mars appears to have cooled so much that it is no longer liquid.

-   The volcanoes in Mars are no longer active

-   There is no Earthquake activity on Mars

## Jupiter

- Jupiter has a strong magnetic field.
- (About 20,000 times stronger than Earth’s)

## Jupiter

- Jupiter has a strong magnetic field.
- (About 20,000 times stronger than Earth’s)

- The Terrestrial planets generate magnetic fields from iron at the center.
- But Jupiter has almost no iron core.

## Jupiter

- Jupiter has a strong magnetic field.
- (About 20,000 times stronger than Earth’s)

- The Terrestrial planets generate magnetic fields from iron at the center.
- But Jupiter has almost no iron core.

- The magnetic field of Jupiter is produced by the motion of liquefied metallic hydrogen found beneath the surface.

## Saturn

- Saturn also has a strong magnetic field.
- (About 540 times stronger than Earth’s)

## Saturn

- Saturn also has a strong magnetic field.
- (About 540 times stronger than Earth’s)

- Saturn’s magnetic field is produced in the same way Jupiter’s is.

## Uranus

- The magnetic field in Uranus is about 40 times stronger than Earth’s

## Uranus

- The magnetic field in Uranus is about 40 times stronger than Earth’s

- It is probably created in the core of the planet,  with ice, rather than with iron.

## Neptune

- The magnetic field in Uranus is about 1/4 times as strong as Earth’s

## Neptune

- The magnetic field in Uranus is about 1/4 times as strong as Earth’s

- It is probably created in the same way as Uranus

## Pluto

- We do not know if Pluto has a magnetic field.

## Pluto

- We do not know if Pluto has a magnetic field.

- Because Pluto has a small size and a slow rotation rate (1 day in Pluto = 6.4 Earth days), it does not seem likely that Pluto has a magnetic field.

## end