juno spacecraft artist conc An artist's concept of the Juno spacecraft. NASA/JPL-Caltech

On July 4, we should get closer to Jupiter than we ever have before.

That's thanks to a NASA mission, Juno, which launched in 2011 and is reaching the planet next week to study it for about a year.

If Juno lives up to expectations, it will totally change our view of the solar system.

The mission will be our first chance to peer beneath Jupiter's thick, stormy atmosphere and into our largest neighbor.

Juno looks like a three-pronged propeller the size of a basketball court, thanks to the unfurled solar panels that are powering it. The propeller spins three times every minute.

While it orbits Jupiter, it will keep the propeller's edge toward the planet, like someone doing a string of cartwheels. The whole system makes Juno more stable, keeps the solar panels in the sun's path, and lets all the instruments on board take turns to get a good look at Jupiter.

About those solar panels: this is the farthest away from the sun that NASA has ever been able to send a solar-powered spacecraft. (The New Horizons spacecraft currently studying Pluto, for example, runs on plutonium.)

Juno's path around Jupiter was carefully calculated to keep it safe from the worst of the planet's very strong radiation. Still, it's a bit of an experiment in understanding how to protect instruments from damaging radiation, something we'll need to get better at the more we want to leave Earth. Engineers designed from scratch a vault to protect the computers and other instruments on board.

It wouldn't be a NASA mission without the promise of beautiful images. Nicknamed Juno Cam, the spacecraft's camera will photograph the tops of the clouds masking the planet. But the radiation will get to Juno Cam pretty quickly — scientists only expect it to last for seven of the spacecraft's 32 planned orbits of Jupiter.

jupiter purple auroras chandra juno Jupiter's auroras, shown here in purple as seen by the Chandra X-Ray Observatory superimposed on a Hubble Space Telescope portrait of the planet. X-ray: NASA/CXC/SwRI/R.Gladstone et al.; Optical: NASA/ESA/Hubble Heritage (AURA/STScI)

One of the instruments on Juno, called JADE (short for Jovian Auroral Distributions Experiment) will be studying Jupiter's huge polar auroras, which can stretch up to tens of thousands of kilometers.

JADE, with the help of a few other instruments, will tally up how many electrons and charged particles (and what kind) are creating the auroras. That should help scientists understand what causes them.

Meanwhile, instruments tracking the planet's gravity will help scientists determine whether Jupiter is all gas or has a solid core buried down there.

That answer, plus how much water Juno finds in the planet's atmosphere, will help scientists figure out if any one of their theories on how the planet formed is actually correct.

Because Jupiter is so humongous, its gravity was strong enough to keep everything that was around when the planet formed, unlike smaller planets which lost lightweight gases. That means Jupiter is a bit like a time capsule that lets us see back to what our neck of the woods was like when the solar system first formed.

When Juno is done with its mission, it will dive towards the center of Jupiter and be destroyed by the planet's atmosphere. But it has a lot of work to do before then.