Juno's mission is to study Jupiter, the largest planet in our solar system.

The spacecraft set off from Earth in August 2011 and will have travelled 1,740 million miles by the time it reaches orbit around Jupiter.

Juno should begin to enter orbit around Jupiter at 4:18am BST on Tuesday 5th July.
After 5 years traveling to #Jupiter, @NASAJuno arrives today! This video shows a peek of its final approach: https://t.co/ysOKuGUWaQ
That's in the evening of 4th July for anyone in the US. A British-made engine will fire to slow down Juno enough for it to enter Jupiter's orbit. NASA engineers refer to this as the "orbit insertion burn".
The "orbit insertion burn" will last for 35 minutes and is the most crucial manoeuvre in the mission so far. If this goes wrong Juno will sail past Jupiter into the abyss of deep space, and it will all have been for nothing.
Once Juno is in orbit it will stay there for 20 months, flying round the gas giant 37 times in total.

Scientists hope to find out how Jupiter formed and what's at its core, among other things.
