An eclipse of the Sun, but instead of the Moon, it's Jupiter that's passing in front. This view was captured by the Galileo spacecraft and shows Jupiter's rings reflecting sunlight. Credit: NASA, JPL, Galileo Project, (NOAO), J. Burns (Cornell) et al.
Move over Saturn. Jupiter also has rings, but they may have been hampered by the planet's colossal moons
We all know about the mesmerising rings of Saturn, but does Jupiter have rings? Yes it does.
OK, so Jupiter doesn’t have large, clearly defined rings like Saturn has, admittedly, but they're there.
In fact, Jupiter’s rings are so faint that they’re invisible to the naked eye, and extremely difficult to spot even with powerful telescopes. But they’re definitely there.
Jupiter's rings seen as two light orange lines, captured by Voyager 2 from a distance of 1,450,000km (900,000 miles). Click to expand. Credit: NASA/JPL
How many rings does Jupiter have?
Jupiter has four main ring structures.
Working outwards from the planet itself there is the thick, inner ‘halo ring’, which is 12,500km thick.
Then the ‘main ring’ which is very bright and very thin, just 30km thick in some parts
And two thick but very faint ‘gossamer rings’.
The halo ring is neutral or blue in colour, while the main and gossamer rings have a reddish hue.
NASA labelled diagram showing the structure of Jupiter's ring system. Jupiter has four ring structures in total. Click to expand. Credit: NASA/JPL/Cornell University
Jupiter rings composition
The rings around Jupiter are thought to consist of material – most of it in the form of very fine particles of dust – that was previously ejected from the moons Metis and Adrastea as the result of collisions with asteroids, meteors or comets.
Whether the rings are as old as Jupiter itself or formed later on is a question that is yet to be answered.
The broad light band crossing diagonally along the centre of this image is the first evidence of Jupiter's rings, seen by Voyager 1 on 4 March 1979. The edge of the ring was 1,212,000km from the spacecraft and 57,000km from the visible cloud deck of Jupiter. Wobbly lines are background stars, their appearance affected by the spacecraft's motion. Click to expand. Credit: NASA/JPL
Discovery
So faint are Jupiter’s rings that we had no idea they were there at all until images were sent back by the Voyager 1 space probe in 1979.
What we know about them today is derived mostly from further imaging by NASA’s Galileo and Cassini missions in the late 90s and early 00s, as well as from observations by the Hubble Space Telescope and the ground-based Keck telescope.
Scientists now believe that it is the gravity from Jupiter’s four large Galilean Moons (Ganymede, Callisto, Io and Europa) that has prevented Jupiter from forming large, well-developed rings like those that encircle its gas giant neighbour, Saturn.
Images of Jupiter's rings
Views of Jupiter's rings as seen by NASA's Galileo spacecraft, 9 November 1996. The top view shows the list of particles above and below the main ring, known as the halo ring. Credit: NASA/JPL/Cornell University
The broad light band crossing diagonally along the centre of this image is the first evidence of Jupiter's rings, as seen by the Voyager 1 spacecraft on 4 march 1979. The edge of the ring was 1,212,000km from the spacecraft and 57,000km from the visible cloud deck of Jupiter. Wobbly lines are background stars, their appearance affected by the spacecraft's motion. Credit: NASA/JPL
NASA labelled diagram showing the structure of Jupiter's ring system. Jupiter has four ring structures in total. Credit: NASA/JPL/Cornell University
Jupiter's rings seen as two light orange lines, captured by Voyager 2 from a distance of 1,450,000km (900,000 miles). Credit: NASA/JPL
An eclipse of the Sun, but instead of the Moon, it's Jupiter that's passing in front. This view was captured by the Galileo spacecraft and shows Jupiter's rings reflecting sunlight. Credit: NASA, JPL, Galileo Project, (NOAO), J. Burns (Cornell) et al.
Jupiter’s rings captured by the James Webb Space Telescope. Credit: NASA, ESA, CSA, Jupiter ERS Team; image processing by Ricardo Hueso (UPV/EHU) and Judy Schmidt.
Jupiter's rings as seen by the Keck Telescope. Credit: Imke de Pater and James Graham (UC Berkeley), and Mike Brown (Caltech).
Russell Deeks is a freelance journalist specialising in science and technology. He has been an occasional contributor to BBC Sky at Night Magazine since 2006.
This website is owned and published by Our Media Ltd. www.ourmedia.co.uk
