Gizmag has followed the progress of NASA's Juno mission with interest and wonder since its launch in 2011. Now that the spacecraft has entered into orbit around Jupiter, what better time to take a closer look at what, precisely, Juno will be able to tell us about the largest planet in our solar system, and its influence on our little corner in space?
Does Jupiter have a solid core?
We think of Jupiter as a gas giant, but the truth is that we have no earthly idea (or should that be unearthly idea?) what lurks beneath its tempestuous clouds. Though Juno won't physically probe beneath the surface, by measuring fluctuations in Jupiter's magnetic and gravitational fields as it orbits, Juno will tell us much more about Jupiter's center. Mind-blowingly, to gauge these gravitational bumps and crevices, scientists will watch the Doppler shift in the radio signal from Juno itself. This should prove or disprove the idea that Jupiter has a solid core composed of things like carbon, nitrogen, oxygen, magnesium, silicon, and iron. Not only that, but we should also get an idea of the core's size, and whether and how it rotates, which may shed new light on the cross-directional weather systems of Jupiter's upper atmosphere.
How was Jupiter formed?
To learn more of Jupiter's composition is to learn more of its origin. If Juno finds no solid core, this would lend credence to the condensed-cloud theory that Jupiter gradually came together out of the gases eddying around during the origins of our solar system. Juno may also tell us whether Jupiter formed in its current orbit, or whether, as some evidence suggests, it originated farther away from the Sun. In turn, knowing more about the origins of this gigantic planet will tell us more of its influence at the birth of the solar system, and therefore the origins of the solar system as a whole, as well as planet Earth.
What influences Jupiter's aurorae?
Earth isn't the only planet in the solar system to boast beautiful illuminated aurorae in its atmosphere at the poles. Whereas the Sun is the origin of the charged particles which cause Earth's northern and southern lights, studies suggest that in Jupiter's case the charged particles are emitted by volcanoes on Io — one of Jupiter's moons. It's thought that Jupiter's speedy rotation and vast magnetic field contribute to the intensity of its aurorae. As well as observing these aurorae, Juno will be able to sample the charged particles from orbit, telling us much more about this beautiful phenomenon.
Excited to learn more about Jupiter? Keep an eye Gizmag's Juno tag for developments. To whet the appetite, check out this timelapse film captured by Juno during its approach to Jupiter, capturing the motion of its moons.