Science Vocab Flashcards
What is the definition of astronomical unit?
It is the average distance between the Sun and the Earth.
It has a measurement of about 149.6 gigametres.
What is the definition of light years?
It is the amount of distance in which light can travel in one year. The distance is roughly the same as 10 trillion kilometers.
What is the definition of parsec?
A unit in astronomy that measures a distance of 3.25 light years.
What is the definition of nebula?
A dusty cloud made of gases in space that is only visible at night. It can look like colorful patches or a dark figure standing against other matter.
What is the definition of a constellation?
A pattern of a group of stars that is named after its figure or mythological being that it shows or represents.
What is the definition of planetesimal?
A body that existed during the formation of the planets.
It can combine itself with other bodies to form a planet under a gravitational force.
What is the definition of protoplanetary?
The embryo of a future planet that has a size of a moon or any other larger planetary object with a protonplanetary disk that has a unique interior. The embryos were formed out of tiny planetesimals.
What is the definition of nuclear fusion?
A nuclei fusion that creates a much larger and heavier nuclei as a result of a nuclear reaction. It releases a massive amount of enegry almost instantly.
What is the definition of terrestrial planets?
A planet that has a rugged surface similar to Earth’s.
They are the four planets that is closest to the sun.
What is a gas giant planet?
A large planet that is made almost entirely of gas.
What is a comet?
A object of heavenly origins that has a inner core made of up of ice and dust. Near the sun, the object is followed by a tail of gas and dust.
Define asteroid.
Small rugged bodies that orbit the sun and are found in the orbits of other planets.
Define cosmologist.
A scientist that studies the the relations of space and time in the universe and its evolution.
Define angular velocity.
A body’s rate of change in its angular position.
What is a planet’s orbit?
The circular movement of a heavenly body or spaceship around planets, stars, or the moon.
