Did you know that Jupiter has rings like Saturn? Only recently have we been able to study them.
The gas giants Jupiter and Saturn have been known about and observed since ancient history. During the Renaissance period and with the dawn of the telescope, Saturn was characterised by its mesmerising ring system whereas Jupiter was the hulking brute of the Solar System, known for the swirling tempest blooming on its south equatorial belt that was later dubbed the Great Red Spot. Scientists identified a similar ring system on Uranus, so when Voyager 1 began its flyby of Jupiter in early 1979, NASA tasked it to look specifically for rings – and it found some. Nearly 20 years later, the Galileo probe entered orbit around Jupiter and was able to study its rings in detail, while New Horizons was able to take high-resolution images revealing the structure of the main ring in its spring 2007 flyby.
Jupiter’s rings are made of four parts and are composed mainly of fine dust of varying grades. A thick ‘halo’ ring orbits the innermost Jovian region, followed by the bright main ring, and the two faint gossamer rings. These gossamer rings are made up of the dust ejected from the two moons, Thebe and Amalthea, which orbit within them, a result of high-energy impacts kicking up debris from their surfaces. The biggest of Jupiter’s rings is the Thebe gossamer ring, which has a radius of around 226,000 kilometres (140,000 miles), a width of 97,000 kilometres (60,000 miles) and a thickness of 8,400 kilometres (5,000 miles).
The rings themselves might have existed as long as Jupiter, although the lifetime of the tiny dust particles in the main ring could be anything from 100 to 1,000 years. It’s continuously being removed from the ring by the Jovian magnetosphere and replenished by impacts between larger objects that are anything from a single centimetre (0.4 inches) up to 500 metres (1,640 feet) in diameter.