Hubble Space Telescope captures 'spokes' moving across Saturn's rings

NASA's Hubble Space Telescope has captured "spokes" moving across Saturn's rings, a phenomenon that indicates the start of the planet's autumnal equinox in its northern hemisphere, CNN reports. The equinox will occur on May 6, 2025.
The reason for the spokes has yet to be discovered, however the "suspected culprit for the spokes is the planet's variable magnetic field," according to NASA. "Planetary magnetic fields interact with the solar wind, creating an electrically charged environment." The space agency compares the phenomenon to the northern lights on Earth.
NASA is hoping that Hubble's new data will either confirm or deny this theory based on the previous data from Voyager and Cassini, which was a designated Saturn probe. "Despite years of excellent observations by the Cassini mission, the precise beginning and duration of the spoke season is still unpredictable, rather like predicting the first storm during hurricane season," explained Amy Simon, a senior planetary scientist at NASA.
Subscribe to The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

Sign up for The Week's Free Newsletters
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
The spokes were last seen in the 2000s. Like Earth, Saturn also experiences seasons, however since Saturn's orbit is much longer than Earth's, each season lasts around seven years. The spokes appear as the planet gets close to its equinox where the rings are tilted toward the sun. The spokes disappear near Saturn's summer or winter solstice.
NASA also explains that while the phenomenon could also occur on other ringed planets like Uranus and Neptune, it has only been observed on Saturn so far. "It's a fascinating magic trick of nature we only see on Saturn — for now at least," remarked Simon.
A free daily email with the biggest news stories of the day – and the best features from TheWeek.com
Devika Rao has worked as a staff writer at The Week since 2022, covering science, the environment, climate and business. She previously worked as a policy associate for a nonprofit organization advocating for environmental action from a business perspective.
-
What are blue slips and why does Trump want to end them?
Today's Big Question The practice lets senators block a president's judge and prosecutor nominees
-
What are 'freakosystems' and how are they affecting the planet?
The explainer Ecosystems are changing permanently
-
'The question is what it does for the ecosystem'
Instant Opinion Opinion, comment and editorials of the day
-
Hurricanes are not exclusive to Earth. They can happen in space.
Under the radar These storms may cause navigational problems
-
Rabbits with 'horns' sighted across Colorado
speed read These creatures are infected with the 'mostly harmless' Shope papilloma virus
-
Why does the US want to put nuclear reactors on the moon?
Today's Big Question The plans come as NASA is facing significant budget cuts
-
Lithium shows promise in Alzheimer's study
Speed Read Potential new treatments could use small amounts of the common metal
-
Scientists discover cause of massive sea star die-off
Speed Read A bacteria related to cholera has been found responsible for the deaths of more than 5 billion sea stars
-
'Thriving' ecosystem found 30,000 feet undersea
Speed Read Researchers discovered communities of creatures living in frigid, pitch-black waters under high pressure
-
Answers to how life on Earth began could be stuck on Mars
Under the Radar Donald Trump plans to scrap Nasa's Mars Sample Return mission – stranding test tubes on the Red Planet and ceding potentially valuable information to China
-
New York plans first nuclear plant in 36 years
Speed Read The plant, to be constructed somewhere in upstate New York, will produce enough energy to power a million homes