The probe, dubbed Osiris-Rex, blasted away from Florida on an Atlas rocket at 19:05 local time (00:05 BST).

The rocket is on its way to to a 500m asteroid called Bennu. The plan is for it to take a sample of this asteroid and return it to Earth in 2023. The Japanease first achieved similar in 2010 when they managed a tiny piece from asteroid Itokawa.

timetable

Osiris-Rex – Mission to Asteroid Bennu

• It’s a two-year journey to Bennu, arriving in August 2018
• After a period of mapping, sampling should occur in July 2020
• Osiris-Rex will have up to three attempts to grab surface material
• The probe will leave Bennu most likely in March 2021
• Its sample capsule should land on Earth on 24 September 2023

Osiris-Rex will spend at least 2.5 years at Bennu.

Source BBC News website