The Earth in Space I Flashcards
shadow
An area of darkness produced when light is blocked by an opaque object
axis
The imaginary line through the earth around which it spins.
day
The period of time when one section of a planet is facing its sun
night
Period of time when one section of a planet is facing away from its sun
year
Length of time it takes for a planet to orbit its sun
seasons
Changes in the climate during the year as the earth moves around its orbit.
poles
The north and south points of the Earth, connected by its axis of tilt.
equator
Imaginary line around the middle of the earth
northern hemisphere
The half of the earth between the equator and the north pole.
southern hemisphere
The half of the earth between the equator and the South Pole
star
Body in space that gives out its own light
atmosphere
The layer of air above Earth’s surface
planets
Any large body that orbits a star in a solar system.
Mercury
The planet nearest the Sun
Venus
A rocky inner planet, the second from the Sun
Mars
A rocky planet, the fourth from the Sun.
asteroid
Irregularly shaped lump of rock in orbit around the Sun
dwarf planet
A lump of rock in orbit around a star that is nearly spherical but has other objects around it.
Pluto
Used to be regarded as the ninth and last planet from the Sun; now called a dwarf planet together with others of the same size that are beyond Pluto’s orbit.
exoplanets
A planet in orbit around a star other than our Sun.