
Uranus has a magnetic field which behaves like a light switch
STATES CHRONICLE – Researchers from Georgia Institute of Technology made an interesting discovery regarding Uranus’ magnetosphere. They found the magnetic field surrounding the planet behaved like a light switch, flipping on and off as Uranus rotated. The study was published in the Journal of Geophysical Research: Space Physics.
Uranus has a different magnetosphere than Earth
In 1986, a NASA spacecraft called Voyager 2 flew by Uranus, and was able to capture some images and data regarding the planet. Now, researchers used this data and discovered interesting facts regarding the planet.
First, the magnetosphere of the planet has one opening, which allows solar wind to fly inside. After some time, the magnetosphere closes, driving the solar wind away. These phenomena take place in a cycle, as compared to Earth’s magnetic field.
Therefore, the solar wind needs to change its direction to cause Earth’s magnetic field to switch between closed and open. This happens since the same side of our planet’s magnetosphere is always facing the Sun. However, Uranus is different.
The magnetic field tumbles against solar winds
The faraway planet rotates on one side, so its magnetic field doesn’t stay straight. In fact, it lies tilted some 60 degrees from the planet’s axis. While Uranus performs its rotation, the magnetosphere moves asymmetrically against the solar wind. Therefore, this rotating speed which changes leads to these opening and closing movements.
“When the magnetized 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.”
This phenomenon of tumbling magnetic fields is widespread all over the Solar System. In fact, it explains the presence of auroras. After gathering all the Voyager 2 data, researchers simulated the movements of Uranus’ global magnetosphere, and were able to tell when and where these openings occur.
Understanding how magnetosphere works is crucial for newly discovered exoplanets. The discovery is vital, since it highlights the complexity of magnetic fields in the universe, and might help in assessing the habitability of new world.
Image Source: NASA Jet Propulsion Laboratory