universe formation Flashcards
Nebula
a large cloud of gas and dust in interstellar space, a region in space where stars are born or where stars expxlode at the end of their lives
Solar Nebula
the cloud of gas and dust that formed our solar system
Nuclear Fusion
the combination of the nuclei of small atoms to form a larger nucleus, releases energy
Sunspot
a dark area of the photosphere of the sun that is cooler than the surrounding areas and that has a strong magnectic field.
Astronomical Unit
the mean distance from the center of the earth to the center of the sun.
Terrestrial Planets
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
Prograde Rotation
Having a rotational or orbital movement that is the same as most bodies within a celestial system. In our solar system, prograde movement for both rotating and orbiting bodies is in a counterclockwise direction when viewed from a vantage point above the Earth’s north pole.
Retrograde Rotation
All eight planets in the Solar System orbit the Sun in the direction that the Sun is rotating, which is counterclockwise when viewed from above the Sun’s north pole
gas giant
a large planet of relatively low density consisting predominantly of hydrogen and helium, such as Jupiter, Saturn, Uranus, or Neptune.
Satellite
an artificial object which has been intentionally placed into orbit. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as Earth’s Moon.
phase
a distinct period or stage in a process of change or forming part of something’s development.
eclipse
an obscuring of the light from one celestial body by the passage of another between it and the observer or between it and its source of illumination.
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 those of the inner Solar System. The larger ones have also been called planetoids.
Asteroid Belt
The asteroid belt is the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets.
