NASA Spacecraft Is About to Enter Jupiter’s Orbit | National Geographic

The scariest thing to me about Juno are the unknowns. So much about the environment that we'll have to withstand is unknown. Nothing's really certain about what's going to happen.

It's a monster. It's unforgiving. It's relentless. It's spinning around so fast; its gravity is like a giant slingshot, slinging rocks, dust, electrons, with whole comets. Anything that gets close to it becomes its weapon sequence.

And just so happens, deep inside this body are the secrets we're after: secrets about our early solar system. It's the biggest and baddest planet in the solar system, and it's got the biggest and baddest radiation and the biggest and baddest magnetic field.

The background radiation that we're exposed to on Earth is about a third of a rad. What we expect to see at Jupiter is about 20 million rad. No spacecraft has ever flown this close to Jupiter, flown this deep into the radiation belts.

So the real trick is we got to go in close, get the data, and get out. And the first time we go in, that's the most dangerous. We call it Jupiter orbit insertion, J.O.I. Nothing's really certain about what's going to happen.