The rotation period for Uranus was estimated at 17.24 hours from radio auroral measurements by NASA’s Voyager 2 spacecraft in 1986. Using long-term tracking of Uranus’ poles between 2011 and 2022 from Hubble images of UV light, astronomers now have an updated independent, highly accurate rotation period of 17.247864 hours, or 28 seconds longer than the estimated Voyager 2.
This image of the Uranus aurora was photographed by Hubble on October 10th, 2022. Image credit: NASA/ESA/Hubble/L. Ramie/L. Slomovsky.
“Our measurements not only provide essential references to the planetary science community, they solve long-standing problems. Previous coordinate systems based on outdated rotation periods quickly become inaccurate, making it impossible to track Uranus’ magnetic poles.
“With this new longitude system, we can compare nearly 40 years of observations of the Aurora and even plan future Uranus missions.”
This breakthrough was possible thanks to long-term surveillance of Hubble’s Uranus.
For over a decade, telescopes have regularly observed their ultraviolet emissions, allowing astronomers to generate magnetic field models that match changes in the position of magnetic poles with time.
“The continuous observation from Hubble was extremely important,” Dr. Lammy said.
“Without this rich data, it would not have been possible to detect periodic signals at the level of accuracy achieved.”
Unlike Earth, Jupiter, or Saturn’s aurora, Uranus’ aurora behaves in a unique and unpredictable way.
This is due to the highly tilted magnetic field of the planet, which is significantly offset from the axis of rotation.
The findings not only help astronomers understand Uranus’ magnetosphere, but also help to provide important information for future missions.
“These discoveries set a stage for further research that will deepen our understanding of one of the most mystical planets in the solar system,” the author said in a statement.
“The ability to monitor objects for decades has allowed Hubble to remain an essential tool for planetary science, paving the way for the next era of exploration on Uranus.”
result It was published in the journal this week Natural Astronomy.
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L. Ramie et al. A new rotation period and longitude system for Uranus. Nut AthlonPublished online on April 7th, 2025. doi:10.1038/s41550-025-02492-z
Source: www.sci.news
