For the first time, a space probe goes to the millions of rocks that fly near the planet Jupiter.
They orbit the sun and are remnants from the time when our solar system was formed billions of years ago.
The launch of the American probe Lucy is scheduled for 11.34 a.m. Dutch time.
Trojan asteroids are called the rocks.
They fly in the same orbit around the sun as Jupiter, located 530 million kilometers away from the sun.
That's about five times as far away as Earth.
The rocks are divided into two groups called swarms.
One half flies ahead of Jupiter, the other half flies after Jupiter.
Lucy has to figure out what they are made of, among other things.
That can tell something about the dust cloud from which the sun, the earth, the other planets and all moons once formed.
To get to her destination, Lucy must embark on a complicated journey.
Earth has to hurl the probe a few times with gravity.
That will happen first in October next year and then again in December 2024.
In April 2025, Lucy will fly past an asteroid between the planets Mars and Jupiter.
Then the probe flies on to the swarm of rocks that fly in front of Jupiter.
In 2027 and 2028, she will visit the asteroid Eurybates and its moon Queta, and the asteroids Polymele, Leucus and Orus.
When that's done, Lucy returns to Earth for a moment.
Our planet must swoop her away in December 2030 towards the other swarm, which flies after Jupiter.
In March 2033 she must arrive at the rocks Patroclus and Menoetius.
When Lucy is there, she has a total of more than 6 billion kilometers on the clock.
The Lucy has huge solar panels to generate electricity.
It is the first time that a probe so far away uses solar energy.
The predecessors ran on nuclear energy.
Lucy is named after a prehistoric skeleton found in Ethiopia in 1974.
It turned out to be a precursor of man.
As that fossil taught scientists more about evolution, the probe should teach scientists more about the evolution of the solar system, the US space agency NASA explains the name choice.Keywords: jupiter.lucy, time, solar system, millions, jupiter, rocks, space probe, launch, journey, probe, remnants, rocks., sun, asteroid, asteroids