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The big bang theory
astrophysicists’ theory which describes how our universe came to existence. And it is the leading scientific explanation so far.
groups of stars representing a certain figure in the sky.
the Earth or the moon passes through a shadow of another heavenly body
is a solid piece of debris from a source such as an asteroid or a comet that originates in outer space and survives its impact on the Earth's surface
it is defined as a branch of astronomy involving the origin and evolution of the universe.
Light Year
how far a beam of light travels in one year. And it’s very long distance - six trillion miles.
Milky Way
the name of a spiral galaxy of which our solar system is part.
Gravitational force
it is the force of attraction between all masses in the universe
Space spinoff
an item that has uses on Earth but was originally developed for use in space.commercial products and services which have been developed with the help of NASA through research and development contracts.
Hubble space telescope
a space telescope that was launched into low Earth orbit in 1990 and remains in operation.
Stephen Hawking
cosmologist who is believed to be one of the greatest scientists alive.
Yuri Gagarin
the first person to travel to space.
Alan Shepard
the first American in space.
Neil Armstrong
the first person to walk on the moon.