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A spacecraft generally gets its energy from at least one of three power sources: the Sun, batteries or unstable atoms.
To choose the best type of power for a spacecraft, engineers consider where it is traveling, what it plans to do there and how long it will need to work.
I trained for a long time to fly airplanes as a fighter pilot.
As we all know, an astronaut needs to be healthy and calm in order to work in space.
First of all, you must be intelligent enough to get a related college degree.
Some scientists were determined to help humans realize their dream to explore space.
On 12 April 1961, Yuri Gagarin became the first person in the world to go into space.
Scientists were determined to help humans realize their dream to explore space.
On 12 April 1961, Yuri Gagarin became the first person in the world to go into space.
Sending people to other planets or even beyond the solar system is not an easy goal to achieve.
Jessie got a new toy to play with.
She has no friend to depend on.
Scientists work hard to find out the secrets of the universe.
As we all know, an astronaut needs to be healthy and calm in order to work in space.
You must be intelligent enough to get a related college degree.
I’m afraid the whole process is too complicate to explain in a few words.
We were surprised to find that he had already left.
Plastic bags cause the deaths of 100, 000 Marine animals each year when the animals mistake them for food, so if you must use them, always recycle them in the bin at your supermarket.
