It's taken five years and $US1 billion, but NASA's Juno spacecraft has successfully placed itself into the orbit of our solar system's largest planet.

The probe has left the orbit of the sun and is now in the desired place to complete its desired orbit around Jupiter.

Loading

Juno has also completed a turn back towards the sun after a tricky entry into orbit, so it has the power to complete its 53-and-a-half day tour.

Loading...

The mission

NASA is on a mission to find out more about the biggest planet in our solar system.

NASA will study the planet's structure, gravity and magnetic field.

Juno set off from Florida in 2011. Now, after travelling 3 billion kilometres it will reach its final destination.

It just completed its next step, tearing through the metal-frying radiation belt that surrounds the gas giant of Jupiter.

Juno fired its rocket to slow itself to a speed of just 250,000 kph and completed the tricky manoeuvre of looping above the planet's billowing clouds of ammonia and hydrogen sulphide.

Instead of entering the atmosphere, it will fall past the face of the planet a total of 37 times, getting as close as 4,700km. Juno will then get snap happy, with the mother of all high-res cameras, as well as measuring its gravitational and magnetic fields.

Why did NASA spend $1b on such a risky mission?

It's hoped getting a closer look at Jupiter will also reveal more about our own planet.

Scientists hope this mission will help unravel how Jupiter formed in the first place.

In turn, that knowledge could help us understand how the Earth and the rest of the solar system developed.

What could have gone wrong?

Getting close to the planet was the hardest part of the mission.

It was fraught with risk and Juno had only one attempt at positioning itself for entering orbit.

The probe fired up its main engine for 35 minutes to shed enough speed so it could be captured by Jupiter's gravity.

But in the process Juno found its way through a veritable minefield of radiation hotspots surrounding the planet, capable of frying its equipment.

Put simply, one wrong move and the space probe could have sailed helplessly past Jupiter.

Wait, there are some passengers on board?

Kind of.

There are three Lego mini-figures of astronomer Galileo, Roman god Jupiter and his wife Juno.

They're made of spacecraft grade aluminium.

It's part of an educational outreach program.

The Australian connection

A team of Canberra space scientists and their array of antennae tracked and commanded NASA's Juno mission.

The 90 CSIRO engineers, technicians and spacecraft communication experts are located at Tidbinbilla south west of Canberra.

Spokesman Glen Nagle says the team tracked pings for the spacecraft that he describes as one billion times weaker than a mobile phone signal.

"Think of us being like the telephone exchange for the universe or air traffic control for space, ensuring that these spacecraft get commands to them to know where to go and what to do and to get all that vital information back in again and off to all those anxious scientists around the planet," Mr Nagle said.

Loading...