NASA’s Hubble Space Telescope has snapped new images of the solar system's seventh planet, Uranus, revealing not only its rings but new secrets about its intriguing moons and how its magnetic field works.
The five largest moons of Uranus – sometimes called the “classical moons” — appear in a jagged, ... More
Hubble's new ultraviolet image of Uranus, taken with its Advanced Camera for Surveys, shows the gas giant planet in space with its five largest moons — often referred to as its “classical moons” — in a jagged line.
The moons — Titania, Oberon, Umbriel, Miranda and Ariel — were captured in the image, which was published on June 10. Ariel can be seen transiting the disk of Uranus, with its shadow apparent on the planet's blue methane-rich atmosphere. All may be “ocean worlds,” which could host life.
The image also shows faint, ghostly rings around Uranus. According to NASA, Uranus has 13 faint rings in total, divided into two distinct sets. In 2023, the James Webb Space Telescope imaged the rings of Uranus and six of its 27 moons and is expected to do so again.
The five largest moons of Uranus – sometimes called the “classical moons” — appear in a jagged, ... More
This new study, presented during a press conference at AAS 246 in Anchorage, Alaska, on Tuesday, June 10, examines the magnetic environment of Uranus and its largest moons. It reveals surprising findings. Scientists had expected that radiation from the magnetic field of Uranus would darken the trailing hemispheres of its moons, but an analysis of the surfaces of Uranus’ four major moons — Ariel, Umbriel, Titania and Oberon — found the opposite. That suggests that Uranus’ magnetosphere might not interact much with its large moons, and it may be either dormant or much more complicated than previously thought. “Uranus is weird, so it's always been uncertain how much the magnetic field actually interacts with its satellites,” said Richard Cartwright, principal investigator at the Johns Hopkins University’s Applied Physics Laboratory in Laurel, Maryland. “For starters, it is tilted by 98 degrees relative to the ecliptic." That means it rolls on its side as it completes its 84-Earth-year orbit of the sun.
The two ice giant planets in the solar system — Uranus and Neptune — remain unexplored, having had only brief flybys by Voyager 2 in 1986 and 1989, respectively. Planetary scientists' lack of detailed knowledge about ice giants (large planets composed mainly of elements heavier than hydrogen and helium) has become more significant in recent years, particularly with research into exoplanets — planets that orbit a star other than the sun. According to research, the most typical size of exoplanets in the Milky Way is between that of Earth and Neptune, which are likely to be ice giants. If astronomers are to understand other star systems, they need a baseline — and that means sending a mission to Uranus or Neptune.
Hopes are fading for a much-needed NASA flagship mission to Uranus. Despite being recommended as NASA's highest priority large mission in 2022 by the National Academy of Sciences, the likelihood of a $4.2 billion orbiter — with an atmospheric probe to dive beneath its clouds — is now small in the light of a “destructive proposal” by the Trump Administration to cut almost $6 billion (24%) from the space agency's budget. Scientists want NASA to send the mission in 2032, with a planned arrival at Uranus in 2045. The next best launch window is in the 2090s.