Scientists have found a new way to measure the magnetic fields of distant planets, especially hot gas giants like Jupiter. Magnetic fields are important because they affect many things on a planet, like its atmosphere and the inside of the planet. But until now, it has been hard to measure these fields.

The new method looks at the speeds of heavy ions (charged particles) and neutral gases using special, high-powered telescopes. Ions are directly affected by magnetic fields, while neutral gases are not. By comparing their speeds, scientists can guess how strong the magnetic field is. For example, if a planet has a magnetic field of 10 Gauss (a way to measure magnetic strength), the speed difference between ions and neutral gases would be about 1 kilometer per second. If the field is stronger, like 50 Gauss, the difference could be up to 20 kilometers per second.

This new method helps scientists understand more about how magnetic fields are made, which can tell us a lot about the inside of these planets and if they might support life. The findings come from both computer models and actual measurements from powerful telescopes. This technique can help us learn more about the magnetic fields of faraway planets and also give us clues about how planets like Jupiter in our own solar system work.