s Flashcards
Divides the terrestrial and Jovian planets and lies between Mars and Jupiter. Distance of the solar nebula from the protostar
Frost Line
Composition of the Universe
4.6% baryonic matter, 24% cold dark matter, and 71.4% dark energy
“ordinary” matter consisting of protons, electrons, and neutrons that comprise atoms, planets, stars, galaxies, and other bodies.
baryonic matter
Matter that has gravity but does not emit light.
Dark Matter
A source of anti-gravity; a force that counteracts gravity and causes the universe to expand, can explain the observed accelerating expansion of the universe.
Dark Energy
three most abundant elements
Hydrogen, Helium, Lithium
Building blocks of galaxies formed by clouds of gas, and dust in the galaxies.
Star/s
The collision of two interacting particles (two light atomic nuclei) at high temperature, and consequent release of relatively large amount of energy into a single heavy nucleus. Responsible for the energy released by stars.
Thermonuclear reaction
Instabilities within the clouds eventually results into gravitational collapse, rotation, heating up, and transformation to a ____, the core of a future star.
protostar
Stars that fuse hydrogen atoms to form helium atom core.
Main Sequence Stars
The distance a light can travel in a year, unit of length that measures astronomical distances.
lightyear
Cluster of stars, at a large scale may seem homogenous and isotropic, but between clusters is empty space.
Galaxy
Cluster of galaxies
Supercluster
The density, age, and diameter of the universe
4.5 x 10-31 g/cm3, 13.8 billion years old, and at least 91 billion light-years
Enumerate the Theories of the Universe
Expanding Universe, The Flat, Close and Open Universes, Steady State Theory, Big Bang Theory, Inflation Theory, Oscillating Universe Theory, String Theory, M-Theory
Galaxies and clusters of galaxies were flying apart from each other. Proposed by Edwin Hubble in 1929, and predicted by Einstein’s Theory of General Relativity.
Expanding Universe (Theory)
leftover light from the Big Bang, discovered by Arno Penzias and Robert Woodrow Wilson in 1964.
Cosmic Microwave Background (CMB)
Discovered the Cosmic Microwave Background in 1964 accidentally, and won the Physics Nobel Prize in 1978.
Arno Penzias, Robert Woodrow Wilson
Theory proposed in 1948 by Hermann Bondi, Thomas Gold, and Fred Hoyle. New matter is created as the universe expand, therefore maintaining its density.
Steady State Theory
Proposed by Alexander Friedmann and Georges Lemaitre in 1920, the universe 13.8 billion years ago, expanded from a singularity, a tiny, dense, and hot mass, into its present size, and cooler state.
Big Bang Theory
Discovered Big Bang Theory in 1920
Alexander Friedmann and Georges Lemaitre
Evidences that back up the Expanding Universe Theory
Redshift, and Cosmic Microwave Background
Ideas that back up the Big Bang Theory
Einstein’s General Theory of Relativity, The Cosmological Principle
Gravity is the distortion of space-time
Einstein’s General Relativity Theory