Aurora Astralis as viewed from the space shuttle.

Destinations:
You might have learned about Earth's aurorae, better known as the northern and southern lights, but why and how do they exist? They exist because our planet has an iron core. This iron core generates a magnetosphere: a magnetic shield around the planet. Streaming particles from our sun are deflected by the magnetosphere which create the spectacular light shows of the northern and southern hemispheres of our planet. The magnetic shield is invisible to the naked eye, but it protects us from high energy solar wind particles that come from our sun and other places.

Jupiter's magnetosphere made visible with Cassini spacecraft imaging.

Not only does our home planet Earth have a magnetosphere, but other planets in our solar system do as well. Jupiter's magnetosphere is so large, that our sun could easily fit inside its volume. The formation of the magnetospheres on other bodies are unique for each planet, but there are a lot of similarities between them. Surprisingly, even comets have magnetospheres.

Some of the moons of planets may also have magnetospheres. The spacecraft Galileo was the first to discover that Jupiter's moon Ganymede has an intrinsic magnetic field.

	Ganymede: a moon with an intrinsic magnetosphere.

Missions:
This month marks the one year anniversary of the Stardust mission. One of the goals of this mission is to learn more about the dust particles that stream past and interact with magnetospheres.

Learn more about the Voyager 1 and Voyager 2 spacecraft. They were some of the first spacecraft that allowed us to discover details of the magnetospheres of the outer planets.

Features:
There is a lot to learn about the complex nature of magnetospheres. Learn more about Saturn's magnetosphere and the components and vocabulary of magnetospheres at Cassini's magnetosphere science section. Magnetospheres even have influence on weather and lightning activity. Learn more about solar system weather by reading Weather, Weather, Everywhere? .

Fast Lesson Finder:
K-12 Activities: Search our Fast Lesson Finder to find classroom lessons related to our solar system and beyond. Some activities related to this month's theme includes Planetary Magnetics , Building Blocks of Planets , Changes Inside Planets, Cosmic Chemistry: An Elemental Question and Looking Inside Planets.

People:
Meet James F. Spann, Jr.: Dr. Spann has been researching plasma physics and magnetosphere interactions for many years on Earth and beyond.

Other Themes