A discovery was made based on the data from NASA’s Voyager 2 spacecraft that flew closely past Uranus the seventh planet from the Sun more than 30 years ago in January 1986.
- Uranus’ magnetosphere, the region defined by the icy planet’s magnetic field and the material trapped inside it gets flipped on and off like a light switch every day as it rotates along with the planet.
- When the magnetised solar wind meets this tumbling field in the right way, it can reconnect and Uranus’ magnetosphere goes from open to closed to open on a daily basis.
- Magnetosphere is open in one orientation, allowing solar wind to flow into it.
- It is later closed, forming a shield against the solar wind and deflecting it away from the planet.
- Uranus’ rapid rotational change in field strength and orientation lead to a periodic open-close-open-close scenario as it tumbles through the solar wind.
Reconnection of magnetic fields is a phenomenon throughout the solar system. It is one reason for the Earth’s auroras.
Source : The Hindu
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