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Thebe [THEE-bee] is the fourth known satellite of Jupiter. Thebe was a nymph and the daughter of the river god Asopus. Thebe rotates synchronously around Jupiter. Very little is known about this moon.
| Views of Thebe |
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Two Galileo Views of Thebe
These two images of the Jovian moon Thebe were taken by Galileo's
solid state imaging system in November 1996 and June 1997, respectively.
North is approximately up in both cases. Thebe, whose longest dimension
is approximately 116 kilometers (72 miles) across, is tidally locked
so that the same side of the satellite always points towards Jupiter,
similar to how the near side of our own Moon always points toward Earth.
In such a tidally locked state, one side of Thebe always points
in the direction in which Thebe moves as it orbits about Jupiter.
This is called the "leading side" of the moon and is shown at the left.
The image on the right emphasizes the side of Thebe that faces away
from Jupiter (the "anti-Jupiter" side). Note that there appear to be
at least three or four very large impact craters on the satellite
-- very large in the sense that each of these craters is roughly
comparable in size to the radius of Thebe.
(Courtesy NASA/JPL)
Discovery Image
This is one of the discovery images (FDS 16383.54) of Thebe.
It was taken by the Voyager 1 spacecraft 4 hours 26 minutes
before the closest approach to Jupiter. This image is a wide
angle picture taken at a range 4.3x105 kilometers. The dark circular
disk is the shadow of Thebe and not the actual planet. Once the
shadow images were analyzed, Thebe was located on several other
images.
(Credit: Calvin J. Hamilton)
Thebe
This image of Thebe (FDS 16220.56) was taken by the Voyager 1 spacecraft
on February 27, 1979. Thebe is the small dark dot above the arrow.
(Credit: Calvin J. Hamilton)
Family Portrait of the Small Inner Satellites of Jupiter
These images, taken by Galileo's solid state imaging system between
November 1996 and June 1997, provide the first ever "family portrait"
of the four small, irregularly shaped moons that orbit Jupiter
in the zone between the planet's ring and the larger Galilean satellites.
The moons are shown in their correct relative sizes, with north approximately
up in all cases. From left to right, arranged in order of increasing distance
from Jupiter, are Metis (longest dimension is approximately 60 kilometers or
37 miles across), Adrastea (20 kilometers or 12 miles across), Amalthea
(247 kilometers or 154 miles across), and Thebe (116 kilometers or 72 miles
across). While Amalthea, the largest of these four tiny moons, was imaged
by NASA's two Voyager spacecraft in 1979 with a resolution comparable to what
is shown here, the new Galileo observations represent the first time that
Metis, Adrastea, and Thebe have been seen as more than points of light.
(Courtesy of NASA/JPL)
| References |
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Synnott, S. P. "1979J2: Discovery of a Previously Unknown Jovian Satellite." Science, Vol 210, 14 November 1980.
Synnott, S. P. "Orbits of the Small Inner Satellites of Jupiter." Icarus 58, 1984.
Jupiter
Amalthea
Io