astronmy Flashcards
Nebula
a cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.
Solar Nebula
Our solar system began forming within a concentration of interstellar dust and hydrogen gas called a molecular cloud.
Nuclear Fusion
a nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.
Sunspot
Sunspots are temporary phenomena on the Sun’s photosphere that appear as spots darker than the surrounding areas
Terrestrial Planets
Within the Solar System, the terrestrial planets are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars.
Prograde Rotation
Having a rotational or orbital movement that is the same as most bodies within a celestial system
Retrograde Rotation
All eight planets in the Solar System orbit the Sun in the direction of the Sun’s rotation,
Gas Giant
a large planet of relatively low density consisting predominantly of hydrogen and helium,
Satellite
In the context of spaceflight, a satellite is an artificial object which has been intentionally placed into orbit.
New Moon
In astronomy, the new moon is the first lunar phase, when the Moon and Sun have the same ecliptic longitude
Waxing Crescent
illumination is growing and ‘Crescent’ means less than half of the Moon is illuminated. This phase signifies intention.
1st Quarter Moon
The First Quarter Moon / Half Moon. The First Quarter Moon is a primary Moon phase when we can see exactly half of the Moon’s surface illuminated.
Waxing Gibbous
Waxing means that it is getting bigger. Gibbous refers to the shape, which is less than the full circle of a Full Moon,
Full Moon
when you can see it all
Waning Gibbous
gibbous Moon rises after sunset, transits the meridian after midnight and sets after sunrise.
Last Quarter Moon
Last quarter: The moon has moved another quarter of the way around Earth, to the third quarter position.
Waning Crescent
Last Quarter - One-half of the Moon appears to be illuminated by direct sunlight.
Solar Eclipse
A solar eclipse occurs when an observer passes through the shadow cast by the Moon which fully or partially blocks the Sun.
Lunar Eclipse
A lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow
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.
Asteroid
Asteroids are minor planets, especially of the inner Solar System. Larger asteroids have also been called planetoids
Asteroid Belt
The asteroid belt is a region of space between the orbits of Mars and Jupiter where most of the asteroids in our Solar System
Meteoroid
a small body moving in the solar system that would become a meteor if it entered the earth’s atmosphere
Meteorite
a meteor that survives its passage through the earth’s atmosphere such that part of it strikes the ground. More than 90 percent of meteorites are of rock,
Meteor
a small body of matter from outer space that enters the earth’s atmosphere, becoming incandescent as a result of friction and appearing as a streak of light.
