The Hubble space telescope has spotted a huge shimmering region on Uranus – and it’s caused by powerful bursts of solar wind.
No giggling at the back, please.
Scientists from the Paris Observatory used the NASA/ESA Hubble Space Telescope to take a look at the auroras on Uranus – caused by streams of charged particles like electrons that come from various origins such as solar winds, the planetary ionosphere, and moon volcanism.
They become caught in powerful magnetic fields and are channeled into the upper atmosphere, where their interactions with gas particles, such as oxygen or nitrogen, set off spectacular bursts of light.
In 2012 and 2014 a team led by an astronomer from Paris Observatory took a second look at the auroras using the ultraviolet capabilities of the Space Telescope Imaging Spectrograph (STIS) installed on Hubble.
They tracked the interplanetary shocks caused by two powerful bursts of solar wind traveling from the sun to Uranus, then used Hubble to capture their effect on Uranus’ auroras – and found themselves observing the most intense auroras ever seen on the planet.
By watching the auroras over time, they collected the first direct evidence that these powerful shimmering regions rotate with the planet.
They also re-discovered Uranus’ long-lost magnetic poles, which were lost shortly after their discovery by Voyager 2 in 1986 due to uncertainties in measurements and the featureless planet surface.
Has Uranus been probed?
NASA’s Voyager 2 spacecraft flew closely past distant Uranus, the seventh planet from the Sun, in January 1986.
At its closest, the spacecraft came within 81,500 kilometers (50,600 miles) of Uranus’s cloudtops on Jan. 24, 1986.
Voyager 2 radioed thousands of images and voluminous amounts of other scientific data on the planet, its moons, rings, atmosphere, interior and the magnetic environment surrounding Uranus.
Since launch on Aug. 20, 1977, Voyager 2’s itinerary has taken the spacecraft to Jupiter in July 1979, Saturn in August 1981, and then Uranus. Voyager 2’s next encounter was with Neptune in August 1989. Both Voyager 2 and its twin, Voyager 1, will eventually leave our solar system and enter interstellar space.
Voyager 2’s images of the five largest moons around Uranus revealed complex surfaces indicative of varying geologic pasts. The cameras also detected 10 previously unseen moons.
Several instruments studied the ring system, uncovering the fine detail of the previously known rings and two newly detected rings.
Voyager data showed that the planet’s rate of rotation is 17 hours, 14 minutes.
The spacecraft also found a Uranian magnetic field that is both large and unusual. In addition, the temperature of the equatorial region, which receives less sunlight over a Uranian year, is nevertheless about the same as that at the poles.