Vocab Solar System Flashcards
(34 cards)
Orbit
the circular path of an object as it revolves around another object
Solar System
a system of objects that revolve around a star
Galaxy
a group of solar systems, dust, and gas held together by gravity; our solar system is part of the Milky Way galaxy
Universe
everything that exists in, on and around the Earth
Satellite
a natural or artificial object that revolves around another object in space
Tides
Rise and fall of the ocean caused by the gravitational pull of the sun and moon.
Impact Crater
The Moon’s surface is covered with bowl shaped holes called craters. The Barringer Crater was made by a meteor that struck Earth thousand of years ago.
Rotation
Rotation is the act of spinning around an axis. Earth rotates on its axis, which is “tilted” in relation to the Sun. This causes our seasons.
Revolution
The movement of an object around another object, in an orbit,is called revolution. Earth completes one revolution around the Sun, every 365.26 days, in an elliptical orbit. The Moon also revolves around Earth in an orbit of 27.3 days.
Season
As Earth revolves around the Sun, it’s tilted axis causes some parts to be pushed toward the Sun and others away from it. During June, the Northern hemisphere is tilted toward the Sun, and places like North America, Europe, and Asia experience summer. During this time, the Southern hemisphere experiences winter.
Equinox
the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length (about September 22 and March 20).
Solstice
A solstice is an astronomical event that occurs twice each year (in June and December) as the Sun reaches its highest or lowest excursion relative to the celestial equator on the celestial sphere. Both the solstices and the equinoxes are directly connected with the seasons of the year.
Eclipse
An eclipse is an astronomical phenomenon caused by the revolution of the Moon around Earth. When the Moon moves into Earth’s shadow, we see a lunar eclipse. When the Moon is positioned directly between Earth and the Sun, its shadow falls on Earth, producing a solar eclipse.
Umbra
the fully shaded inner region of a shadow cast by an opaque object, especially the area on the earth or moon experiencing the total phase of an eclipse.Compare with penumbra.
Penumbra
the partially shaded outer region of the shadow cast by an opaque object.
Astronomical unit
Astronomical unit is used to measure distance in the solar system. The distance from Earth to the sun is 1 AU and the distance from Mars to the sun is 1.5 AU.
Eclipse
On a sunny day, the ground is covered with shadows because objects block the Sun’s light. When Earth is between the Sun and the Moon, it casts a shadow on the Moon, covering it. This is called a lunar eclipse. A solar eclipse occurs when the Moon passes between the Sun and Earth, casting its shadow on Earth
Terrestrial planet
A terrestrial planet, telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals. Within the Solar System, the terrestrial planets are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars.
Gas giants
A gas giant is a giant planet composed mainly of hydrogen and helium. Jupiter and Saturn are the Solar System’s gas giants. The term “gas giant” was originally synonymous with “giant planet”, but in the 1990s it became known that Uranus and Neptune are really a distinct class of giant planet, being composed mainly of heavier volatile substances (which are referred to as ‘ices’).
Asteroid
Asteroids are irregularly shaped rocks that revolve around the Sun. Most asteroids are present in a band located between the orbits of Mars and Jupiter, known as the asteroid belt.
Comet
Comets are balls of ice and rock that are seen moving across the sky. A comet’s body has two parts, a head and a tail. Comets move about the Solar System in orbits that take them far from the Sun. As they revolve around the Sun, their tail grows longer because the ice in the head boils away.
Meteor
A view of the night sky might include a fast streak of light that quickly disappears. You might call it a “Shooting Star”. It is actually a meteor.
Meteorite
When a meteoroid moving away from the asteroid belt hits Earth’s surface, it is called a meteorite. Due to the tremendous impact, a crater is formed on Earth’s surface where the meteorites strike.
Geocentric
When the Earth is placed at the center of a system, the system is said to be geocentric. The Moon revolves around the Earth. The Earth-Moon system is geocentric.