continuing in the promised series about moons I will today cover the satellite Thebe, this time I even have some “high resolution” pictures so keep on reading!
Thebe is another Jupiter‘s moon. It is quite smaller than Amalthea, with 100 kilometers as mean diameter. It was named for Greek nymph, in both stories I found, she was lover of Zeus (yet again) but in one she was also the daughter of Egyptian king.
It is quite similar to Amalthea, again it is tidally locked, which means that one side always turns toward Jupiter (this is also true for Moon). The surface is probably red what you can not see on black and white pictures of course. We can estimate its mass only based on the similarity with Amalthea, the value you will get is roughly 4*10^17 kilograms.
For the first time its image was taken back in 1979 by Voyager. Later, Stephen P. Synnott found it on one picture. Four years later the name we use was first used.
The above picture is the first sign of another moon, but watch out, this one is only shadow.
Another picture of Jupiter but this time Thebe is really visible! (Yeah it is not just filth on you monitor).
Finally, Jupiter has faint rings. These rings have to made up of something. Usually rings are created when some rocks are ripped apart by tidal forces. Also they can be fed over long periods of time be debris that leaves some moons.
Thebe has one very faint ring which is created by the second method. It is three times fainter than the ring of Amalthea which is very faint too. It has diameter of 65k-113k kilometers and it is not so thin (8400 km) as the Saturn’s rings which are even only several meters tall.
PS: the second and third pictures were taken from the same site and official permission should be needed only for commercial purposes, which is not me.
S/1979 J 2 was the original name, though I did not decode it it probably means S=satellte 1979=the year it was found J=Jupiter 2=probably second in row with this designation.