What is the extent of a planet's magnetic field in space?

What is the extent of a planet's magnetic field in space?

• A. Core field
• B. Geomagnetic belt
• C. Magnetosphere
• D. Inner field

Answer: (C)

The extent of a planet’s magnetic field in space is the magnetosphere. This is the protective bubble around a planet where the magnetic field still dominates the motion of charged particles, shaped by the solar wind. On the dayside it is compressed to about ten planetary radii from the planet, while the field stretches far into a long tail on the nightside. The other terms refer to internal or nearby features—core or inner field describe the planet’s interior field, and the geomagnetic belts are bands of charged particles inside the magnetosphere, not its overall extent. So the best answer is the magnetosphere.

The extent of a planet’s magnetic field in space is the magnetosphere. This is the protective bubble around a planet where the magnetic field still dominates the motion of charged particles, shaped by the solar wind. On the dayside it is compressed to about ten planetary radii from the planet, while the field stretches far into a long tail on the nightside. The other terms refer to internal or nearby features—core or inner field describe the planet’s interior field, and the geomagnetic belts are bands of charged particles inside the magnetosphere, not its overall extent. So the best answer is the magnetosphere.