Re: 'Why does Neptune have arcs, not rings?'

As seen from Earth, the rings of planet Neptune are not complete, they only exist of arcs. This is why ever since the discovery of Neptune in 1846, all scientists have believed that Neptune's ring-system is incomplete.

But in August 1989 the space-explorer Voyager-2 arrived at Neptune, after visiting Jupiter (1979), Saturn (1981) and Uranus (1986). Never before had Neptune been examined from such a short range.

And Voyager-2 discovered a few things: Neptune did not - as people thought - have two moons, but eight! And what might interest you: the rings of Neptune turned out to be as ring-shaped as a frisbee; Neptune doesn't have arcs at all, only ordinary rings!

In one of the three rings there are spots which have slightly more fragments (rocks, ice, etc.). And these spots misled all scientist for over a hundred years: as seen from Earth, they made the rings look like arcs.

This is possible due to the fact that Neptune is very far away from Earth, usualy at a distance of over 4,500,000,000 kilometers (2,812,500,000 miles) and therefore is not easy to examine from Earth.

But the rings of Neptune are NOT arcs. They are as normal as the rings from the other gasplanets (Jupiter, Saturne, Uranus and Neptune are gasplanets).