Page 8 - Curriculum Visions Dynamic Book

Jupiter is the real giant of the solar system. It is 318 times more massive than the Earth, with a volume 1,500 times as great.
It has an intense magnetic field and an internal heat source. It sends out to space more heat than it receives from the Sun. In radio waves Jupiter actually can send out more energy than the Sun.
Jupiter is almost big enough to have become a star in its own right. It is the fifth planet in distance from the Sun. It is visible with the naked eye and is named
after the Roman ruler of the gods.
Although not as famed as Saturn for its rings, Jupiter has them, along with moons included in them, which are among the most spectacular of the bodies in the solar system. Jupiter’s narrow rings include 16 moons, of which four are larger than our Moon and one bigger than the planet Mercury. The major moons (outward from the planet)
are Io, Callisto, Ganymede, and Europa
(see pages 21–34).
Much of our knowledge of Jupiter
comes from the space probes Pioneer
10 and 11 and Voyager 1 and 2 (see page 27), all of which passed Jupiter in the late 1970s. We got so much information that it is still being analyzed.
A lightweight, surfaceless planet
Despite its massive size and large gravity, Jupiter is a lightweight planet, having a density of 1.3 g/cm3, only a bit more dense than water. It is less than a quarter as dense as the Earth. This, above all, tells us that the structure of Jupiter must be very different from that of the Earth.
 Jupiter—the giant of the solar system.
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