Astronomers have made a major breakthrough in understanding Uranus, one of the solar system’s most mysterious planets.
Using over ten years of data from the Hubble Space Telescope, scientists have figured out exactly how long it takes Uranus to spin once on its axis.
The new result is far more accurate than anything we’ve had before—1,000 times more precise than earlier measurements.
The team of researchers, led by Laurent Lamy from the Observatoire de Paris-PSL and Aix-Marseille University in France, found that Uranus completes one full rotation in exactly 17 hours, 14 minutes, and 52 seconds.
That’s 28 seconds longer than what NASA’s Voyager 2 spacecraft had estimated when it flew by the planet back in 1986.
This might seem like a small difference, but it’s a big deal for scientists.
For years, they struggled to track Uranus’ rotation because there was no accurate reference point.
Earlier estimates caused problems over time—like a watch that gradually falls out of sync—making it hard to follow the planet’s magnetic features or compare past observations.
To solve this problem, the team used a clever new method. They studied Uranus’ aurorae—beautiful, glowing lights in the planet’s upper atmosphere, caused by charged particles from space hitting the magnetic field near the poles.
These aurorae are like natural beacons that rotate with the planet. By tracking the motion of these lights, scientists were able to “time” Uranus’ spin with incredible precision.
The reason this worked so well is thanks to Hubble’s consistent, long-term observations. Over more than a decade, the space telescope kept watching the ultraviolet light from Uranus’ aurorae, giving scientists a steady stream of data to analyze.
This allowed them to detect the planet’s rotation signal more clearly than ever before.
Unlike Earth or even Saturn and Jupiter, Uranus is a very unusual planet. Its magnetic field is tilted at a strange angle and doesn’t line up with its spin axis, which makes its aurorae behave in unpredictable ways.
Understanding how Uranus spins helps researchers better understand its magnetosphere—the protective magnetic bubble around the planet.
This new measurement comes at the perfect time. The U.S. has chosen the Uranus Orbiter and Probe mission as a top priority for future space exploration. Thanks to Hubble and this new research, scientists now have a solid foundation for planning that mission.
As Hubble continues to watch the skies, its role in revealing the secrets of distant planets remains as important as ever. With this new discovery, we’re one step closer to unlocking the many mysteries of Uranus.
Source: European Space Agency.
