The outer layers of the jovian planets are neither warm enough nor solid enough for human habitation. Any bases we build in the systems of the giant planets may well have to be in space or one of their moons—none of which is particularly hospitable to a luxury hotel with a swimming pool and palm trees.
Perhaps we will find warmer havens deep inside the clouds of Jupiter or in the ocean under the frozen ice of its moon Europa. All of this suggests that we had better take good care of Earth because it is the only site where life as we know it could survive.
Recent human activity may be reducing the habitability of our planet by adding pollutants to the atmosphere, especially the potent greenhouse gas carbon dioxide. Human civilization is changing our planet dramatically, and these changes are not necessarily for the better.
In a solar system that seems unready to receive us, making Earth less hospitable to life may be a grave mistake. The crusts of all of the terrestrial planets, as well as of the larger moons, have been modified over their histories by both internal and external forces. Externally, each has been battered by a slow rain of projectiles from space, leaving their surfaces pockmarked by impact craters of all sizes see Figure 3 in Overview of Our Planetary System.
We have good evidence that this bombardment was far greater in the early history of the solar system, but it certainly continues to this day, even if at a lower rate.
The collision of more than 20 large pieces of Comet Shoemaker—Levy 9 with Jupiter in the summer of see Figure 3 is one dramatic example of this process. Figure 3: Comet Shoemaker—Levy 9. The comet was approximately million kilometers from Earth, heading on a collision course with Jupiter.
Weaver STScl , E. Smith STScl. Figure 4: Jupiter with Huge Dust Clouds. The Hubble Space Telescope took this sequence of images of Jupiter in summer , when fragments of Comet Shoemaker—Levy 9 collided with the giant planet. Here we see the site hit by fragment G, from five minutes to five days after impact. Several of the dust clouds generated by the collisions became larger than Earth.
Hammel, NASA. During the time all the planets have been subject to such impacts, internal forces on the terrestrial planets have buckled and twisted their crusts, built up mountain ranges, erupted as volcanoes, and generally reshaped the surfaces in what we call geological activity.
Among the terrestrial planets, Earth and Venus have experienced the most geological activity over their histories, although some of the moons in the outer solar system are also surprisingly active. In contrast, our own Moon is a dead world where geological activity ceased billions of years ago. Geological activity on a planet is the result of a hot interior. Jupiter has tremendous thunderstorms in its atmosphere and also aurorae.
The planet Jupiter is one of the brightest objects in the night sky. A combination of its orbital period, It is then very bright. With a pair of binoculars, you can see the four moons discovered by Galileo. These are the four largest of Jupiter's family of 16 satellites which all lie within the magnetsphere extending km into space. The diameters of the biggest, Io, Europa, Ganymede and Callisto range between and km whereas the smallest, Leda has a diameter of only 10 km.
The names of all of Jupiter's satellites come from mythological lovers of Jupiter, except Amalthea, who was his nurse. Io, the closest of the four large moons to Jupiter, is the most fantastic. Jupiter is a gas giant and so lacks an Earth-like surface. Jupiter's atmosphere is made up mostly of hydrogen H 2 and helium He. All four giant planets in our solar system have ring systems.
Nine spacecraft have visited Jupiter. Seven flew by and two have orbited the gas giant. Juno, the most recent, arrived at Jupiter in Jupiter cannot support life as we know it. But some of Jupiter's moons have oceans beneath their crusts that might support life. The biggest planet in our solar system, Jupiter also has a large presence in pop culture, including many movies, TV shows, video games, and comics. Jupiter is the biggest planet in our solar system. It's similar to a star, but it never got big enough to start burning.
Jupiter is covered in swirling cloud stripes. It has big storms like the Great Red Spot, which has been going for hundreds of years. And just because it had a core in the past doesn't mean that it still will today — new evidence suggests that the gas giant's core may be melting. Like the sun, Jupiter is composed predominantly of hydrogen and helium. But unlike the sun, it lacks the necessary amount to begin fusion , the process that fuels a star.
Jupiter would need to be 75 to 80 times more massive than it is at present to be considered a star. If all of the planets in the solar system had formed as part of the gas giant, it still would not have sufficient mass.
Still, by itself, Jupiter is two and a half times larger than all of the other planets in the solar system combined. Join our Space Forums to keep talking space on the latest missions, night sky and more!
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