The Juno NASA spacecraft has provided some of the most impressive insights into the gas giant humanity has ever seen, but it has also taught scientists much about how the planet works. We now know that his storms are far deeper into the planet than previously thought and that Jupiter's lightning is very similar to Earth's here.
Now, the data collected by Juno has illuminated another aspect of Jupiter that seems much like Earth. In a new article published in Nature Astronomy scientists reveal that Juno's measurements of the Jupiter magnetic field deviate from the observations of past missions. This suggests that the planet's magnetic field is actually changing in a small but important way, much like Earth's magnetic field changes.
For the study, NASA scientists compared recent measurements of the Jupiter magnetic field with data collected over years previously from missions such as Voyage and Pioneer. Juno's multiple passes of Jupiter and his magnetometer have provided a wealth of information about the planet's magnetic field today, and the researchers quickly noticed the differences.
"Finding something as tiny as these changes in something as vast as Jupiter's Magnetic Field was a challenge," said Juno scientist Kimee Moore in a statement. "A near-observation baseline of four decades has just given us enough data to confirm that Jupiter's magnetic field actually changes over time."
These small changes suggest that Jupiter is experiencing a phenomenon known as Secular Variation happening here on Earth. On our own planet, worldly variation is attributed to changes that take place deep below the surface, and Jupiter assumes that intense winds well below the cloud tops are the engine that drives the changes.
This is an important discovery for scientists. We are still trying to learn more about the Earth's magnetic field, and the Juno team plans to continue tracking the changes in Jupiter magnetism in the future.