Space Vocabulary for school Flashcards
(34 cards)
Orbit
The orbit of the Moon is nearly circular. The planets in the solar system have a slightly elliptical orbit, while the orbit of comets is highly elliptical.
Solar system
The orbits of the planets and the position of the Sun are fixed – they do not change. We always know where the planets and Sun will be. This system is called solar because the planets are controlled by the Sun’s gravity.
Galaxy
Our solar system is located in a galaxy known as The Milky Way.
Universe
Earth and the other planets of the solar system are all a part of the Milky Way Galaxy. The universe has numerous galaxies, like the Milky Way.
Satellite
The Moon is a natural satellite that orbits Earth. The planet Jupiter has many moons, four of which are Io, Europa, Ganymede, and Callisto. Artificial satellites are made by man and launched to orbit Earth and other planets.
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.
Aphelion
Mercury has a very elliptical orbit. The position in the orbit when it is farthest from the Sun is its aphelion.
Perihelion
Planets revolve around the Sun in elliptical orbits. The point in the orbit of a planet where the planet is closest to the Sun is its perihelion. At perihelion, Earth is 147 million km away from the Sun.
Quarter moon
The Moon is a natural satellite that revolves around Earth. Mars has two moons, Phobos and Deimos, while Jupiter has over 63 moons. The most prominent of these are Ganymede, lo, Europa, and Callisto. Satellites launched into space orbit around Earth are man-made moons.
Tide
A tide is a periodic variation in the surface level of bodies of water caused by gravitational attraction of the Moon and Sun. The water levels during the tides vary with the relative positions of the Sun and Moon with respect to Earth.
Gravity
The pull of gravity on the Earth and on the Moon is different. Earth is much larger than the moon. So, its mass is greater and the gravitational pull here is 9.8 m/s2. But on the Moon, the gravitational pull is only 1.6 m/s2. So, an object will weigh less on the Moon than it does on Earth.
Heliocentric
Heliocentric comes from the Greek word “helios”, meaning Sun. The Sun is the center of the solar system. All the planets in the solar system orbit around the Sun.
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.
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.
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.
Comet
Comets are balls of ice and rock, held together by frozen gases. Comets travel in elongated orbits around the Sun. As they approach the Sun, the frozen gases vaporize, forming a tail.
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.
(AU)
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
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.
Solstice
Because Earth’s rotation axis is tilted relative to its orbital path around the Sun, the apparent path of the Sun across the sky changes with the seasons. In the summer, the Sun gets higher in the sky than in the winter. The summer solstice is the day that the mid-day Sun reaches its highest point in the sky. The winter solstice is the day that the mid-day Sun is lowe
Equinox
An equinox is a date of the year when daylight and nighttime each last 12 hours everywhere on Earth. On all other days of the year, day and night last different amounts of time, and differ in length from location to location on Earth. There are two equinoxes each year. They occur when the plane of Earth’s tilt is tangent to its orbital plane. As a result, neither hemisphere is tilted toward or away from the Sun.
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.
New moon
the phase of the moon when it is in conjunction with the sun and invisible from earth, or shortly thereafter when it appears as a slender crescent.
Full moon
the phase of the moon in which its whole disk is illuminated.
