Astronomy Flashcards
(22 cards)
What is the definition of astronomical unit?
Average distance between sun and the earth.
What is the definition of Light year?
Distance light goes in one year.
What is the definition of Nebula?
A cloud of dust and gas.
What is the definition of Parsec?
To describe large distances one parsec equals 3.26 light years proxima centauri is 1.29 away.
What is the definition of constellation?
When stars at night makes a pattern.
What is the definition of planetesimal?
bodys that could come together to form a planet.
What is the defintion of protoplanetary?
Protoplanets are moon-sized or larger planetary embryos within protoplanetary discs that have undergone internal melting to produce different interiors.
What is the definition of Nuclear fusion?
A nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.
What is the definition of terrestrial planets?
a planet having a compact rocky surface like the Earth’s the four innermost planets in the solar system
What is the definiton of gas giant plants?
A type of planet characterized by being composed almost entirely of gas.
What is comet?
A celestial object consisting of a nucleus of ice and dust and, when near the sun, a “tail” of gas and dust particles pointing away from the sun.
What is Asteroid?
A small rocky body orbiting the sun. Large numbers of these, ranging in size from nearly 600 miles.
What is Cosmologist?
An astronomer who studies the evolution and space-time relations of the universe.
What is angular velocity?
The rate of change of angular position of a rotating body.
What is Orbit?
The curved path of a celestial object or spacecraft around a star, planet, or moon.
What is Period?
A length or portion of time.
What is Revolve?
The action of rotating around an axis or center.
What is rotation?
It means to go round.
What is sidereal day?
The time between two consecutive transits of the First Point of Aries, almost four minutes shorter than the solar day because of the earth’s orbital motion.
What is solar day?
The time between successive meridian transits of the sun at a particular place.
What is year?
The period of time that it takes for a planet earth or mars to make a complete revolution around the sun.
What is accretion?
Accretion is the process of growth or increase.
