ITV News' science correspondent Alok Jha reports.
A space probe is just hours away from completing its five-year, 1.4 billion mile journey from Earth, and entering Jupiter's orbit.
Once successfully orbiting Jupiter, the Juno spacecraft will investigate how much oxygen and water the planet holds, and will look beneath the planet's clouds to discover what lies in its core. It is hoped that the investigations will unlock the history of the early solar system.
It will be a nail-biting end to the journey for the team behind the mission, as if something goes wrong, Juno will miss the planet's orbit and simply continue on into space.
However, should everything go alright, it still will not be plain sailing for the probe and its Buckinghamshire built engine, as it will have to contend with some of the harshest radiation in the whole solar system.