Cosmology and the birth of the earth Flashcards
Cosmology
The study of the universe and its history
Telescope
A device used to make objects far away, appear closer such as planets
Remote Sensing
When information about a planet is gathered using a satelite
Meteorite
A piece of debris that has fallen into the earth from outer space
Lightyear
The distance that light travels in one year
Star
A ball of gas which is held together by its own gravity, of which planets orbit
The Doppler Effect
When waves approaching an object have higher frequencies and lower wavelengths, while waves moving away from an object have lower frequencies and higher wavelengths
Red Shift
An increase in wavelength
Blue Shift
A decrease in wavelength
How do we know that the universe is expanding by using The Doppler Effect?
Light seen from other galaxies are increasing in wavelength (red-shifted) meaning that galaxies are moving further away from each other and the universe is expanding
Why do distant galaxies move faster away from each other?
As space is expanding so does the distance between galaxies
Big Bang
The birth of the universe
Matter
Anything which has mass and volume (occupies space)
Nuclear fusion
When light elements (hydrogen, helium, lithium) combine to form one nuclei (nucleus) resulting in the release of energy
Big Bang Nucleosynthesis
The formation of light elements (hydrogen, helium, lithium)
Nebula
A cloud of gas and dust occupying the space between stars
Nebular Theory/Hypothesis
A theory which states that a nebula collapsed under its own gravity to form a swirling disk and eventually the solar system
Nebular Theory/Hypothesis
A theory that states that the solar system was formed from a collapsing nebula.
Stellar Nucleosynthesis
Formation of atoms (more complex than hydrogen) up to iron as a result of nuclear fusion
Coalesce
To come together to form a greater mass
Supernova
The explosion of a star which causes the star to become brighter
Terrestrial planets are made up of
Refractory (Solids) materials
Gast giants are made up of
Volatile (easily evaporated at normal temperatures) gases and ice
Formation of terrestrial planets are
Homogeneous (the same), (mercury, venus, earth and mars were formed the same way)
How was the earth created
When gas and dust was pulled together by gravity, as well as from heat and radioactive decay
Why planets are round
Planets are round because gravity pulls all of a planet’s mass inwards, smoothening any edge/non-roundness
How the moon was formed
When an object collided with earth and as a result, the debris formed the moon
Planetismal
An object formed by rock and dust
