BIG BANG
This is the name of the theory that proposes the universe began from a single, extremely dense point.
Big Bang Theory
This theory explains that the solar system formed from a rotating disk of gas and dust.
NEBULAR HYPOTHESIS
This outdated theory proposed that a passing star pulled material from the Sun to form planets.
TIDAL THEORY
The redshift of galaxies provides evidence that the universe is doing this.
EXPANDING
This term describes the scientific study of the origin and structure of the universe.
COSMOLOGY
According to the Big Bang Theory, this force caused the initial expansion of the universe.
In the early solar system, small particles clumped together to form these larger bodies.
PLANETISIMALS
The "steady state theory" was challenged by this type of observational evidence showing a changing universe.
REDSHIFT OF GALAXIES
This NASA telescope has helped confirm theories about the age and expansion of the universe.
HUBBLE SPACE TELESCOPE
This term refers to the point in time when the universe was infinitely hot and dense.
SINGULARITY
The discovery of this cosmic phenomenon in 1965 provided strong evidence for the Big Bang Theory.
Cosmic Microwave Background Radiation
This central body formed first in the solar nebula and captured most of the mass.
SUN
This theory was proposed as an alternative to the Big Bang, but lacked evidence of cosmic background radiation.
STEADY STATE THEORY
This faint microwave signal is a relic of the early universe.
COSMIC MICROWAVE BACKGROUND
This branch of physics is key to understanding events just after the Big Bang.
QUANTUM PHYSICS/ PARTICLE PHYSICS
This element, along with hydrogen, was one of the first formed in the early universe.
HELIUM
These icy objects found beyond Neptune are remnants of the early solar system.
KUIPER BELT
According to this theory, stars and planets form through the gradual accumulation of gas and dust.
ACCRETION THEORY
The abundance of light elements like hydrogen and helium supports this theory of the universe's origin.
BIG BANG THEORY
According to theory, dark matter makes up this percentage (approximate) of the universe.
27%
This concept refers to the rapid expansion of the universe in the first fraction of a second after the Big Bang.
COSMIC INFLATION
The inner planets are rocky because this process pushed lighter gases farther out.
SOLAR WIND
The modified nebular hypothesis includes this key addition to explain angular momentum distribution.
CONSERVATION OF ANGULAR MOMENTUM
Planetary orbits in the same direction support this model of solar system formation.
NEBULAR HYPOTHESIS
This hypothetical force is driving the acceleration of the universe's expansion.
DARK ENERGY