Skip to main content

Uranus is losing its atmosphere because of its weird wobbly magnetic field

Voyager 2 may have long ago left our solar system and headed out into interstellar space to explore the unknown, but scientists are still learning from the data it collected as it passed by the other planets in our system. A new analysis of 30-year-old data has revealed a surprising finding about the planet Uranus — the huge magnetic bubble surrounding it is siphoning its atmosphere off into space.

Atmospheres being lost into space can have a profound effect on the development of a planet. As an example, Mars is thought to have started out as an ocean-covered planet similar to Earth but lost its atmosphere over time. “Mars used to be a wet planet with a thick atmosphere,” Gina DiBraccio, space physicist at NASA’s Goddard Space Flight Center and project scientist for the Mars Atmosphere and Volatile Evolution, or MAVEN mission, said in a statement. “It evolved over time to become the dry planet we see today.”

Recommended Videos

Uranus’s atmospheric loss is driven by its strange magnetic field, the axis of which points at an angle compared to the axis on which the planet spins. That means its magnetosphere wobbles as it moves, which makes it very difficult to model. “The structure, the way that it moves,” DiBraccio said, “Uranus is really on its own.”

Voyager 2 took this image as it approached the planet Uranus on Jan. 14, 1986. The planet's hazy bluish color is due to the methane in its atmosphere, which absorbs red wavelengths of light.
Voyager 2 took this image as it approached the planet Uranus on Jan. 14, 1986. The planet’s hazy bluish color is due to the methane in its atmosphere, which absorbs red wavelengths of light. NASA/JPL-Caltech

Due to the wobbling of the magnetosphere, bits of the atmosphere are drained away in what are called plasmoids — bubbles of plasma which pinch off from the magnetic field as it is blown around by the Sun. Although these plasmoids have been seen on Earth and on some other planets, they had never been observed on Uranus before the recent analysis of old Voyager 2 data.

“Imagine if one spacecraft just flew through this room and tried to characterize the entire Earth,” DiBraccio said. “Obviously it’s not going to show you anything about what the Sahara or Antarctica is like.”

“It’s why I love planetary science,” DiBraccio said. “You’re always going somewhere you don’t really know.”

The research is published in the journal Geophysical Research Letters.

Georgina Torbet
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
SpaceX suggests potential cause of huge Starship explosion
SpaceX's Starship spacecraft explodes at Starbase.

SpaceX has offered an update on the massive explosion which destroyed the Starship spacecraft on a test stand on Wednesday.

The dramatic explosion took place at SpaceX’s Starbase facility near Boca Chica, Texas, during preparations for the Starship rocket’s 10th test flight, which was expected to take place in the coming weeks. No one was reported killed or injured in the incident.

Read more
These 6 rocket explosions show how SpaceX likes to roll
A Starship prototype explodes during testing.

The upper-stage of SpaceX’s next-generation Starship rocket exploded in a massive fireball at its Starbase facility near Boca Chica, Texas, on Wednesday night. No one was hurt in the incident.

The vehicle was being prepared for the 10th flight test of the most powerful rocket in the world, which also includes the first-stage Super Heavy booster.

Read more
Watch this Atlas rocket zip to the launchpad for Amazon’s Kuiper launch
ULA's Atlas V rocket on the launchpad at Cape Canaveral for the second Project Kuiper satellite deployment.

United Launch Alliance (ULA) has started the countdown clock for the deployment of Amazon’s second batch of Project Kuiper internet satellites.

The rocket operator released a time-lapse video on Sunday showing the Atlas V rocket moving from the Vehicle Assembly Building to the launchpad at Cape Canaveral in Florida. ULA chief Tory Bruno noted that while the rocket appears to hurtle to its destination, the vehicle carrying it is actually moving at a mere 3 mph.

Read more