12 more images in gallery
At first blush Jupiter may seem like a rather dull planet. A failed star. A ball of gas. A large, red storm. Sure, it's big, but what more is there? And we’ve been there before—lots of times, in fact. Beginning with Pioneer 11 and 12, NASA has flown seven probes by the gas world. One mission, Galileo, studied the Jovian system for nearly a decade from 1995 to 2003. So why is the space agency sending yet another probe, Juno, to once again visit the solar system's giant?
We're still studying Jupiter because despite all of these missions NASA has literally only scratched the surface. Its inner structure remains largely a mystery—and an intriguing one, too. The planet is essentially made of gas piled upon more gas. And like a big stack of pillows, as more gas is added on top, the bottom layers become more and more compressed as gravity pulls down on the gas. This creates extremely dense conditions inside the planet. Jupiter, after all, is only a little bit larger than Saturn—but it has three times the mass. Scientists have almost no idea how hydrogen will behave at the extreme pressures deep beneath Jupiter's outer layers toward its core. Indeed, does Jupiter even have a core? We simply don’t know.
The Juno spacecraft, launched in 2011 and arriving at Jupiter on July 4th this year, will be able to scrutinize the planet's gravity field and peer beneath its upper cloud layer. This should help offer some clarity about Jupiter’s interior. During a presentation in May at the Lunar and Planetary Institute in Houston, mission scientist Fran Bagenal discussed just how strange that interior might be.
No comments:
Post a Comment