Search results
Results from the WOW.Com Content Network
The universe is all of space and time [a] and their contents. [10] It comprises all of existence, any fundamental interaction, physical process and physical constant, and therefore all forms of energy and matter, and the structures they form, from sub-atomic particles to entire galactic filaments. Space and time, according to the prevailing ...
The cosmos ( Ancient Greek: κόσμος, romanized : Kósmos, / ˈkɒzmɒs /, US also /- moʊs, - məs /) [1] is an alternative name for the universe or its nature or order. Usage of the word cosmos implies viewing the universe as a complex and orderly system or entity. [2]
v. t. e. The Big Bang was the initiation of the continuing expansion of the universe from a state of high density and temperature ( its central singularity ). [1] It was first proposed as a physical theory in 1931 by Roman Catholic priest and physicist Georges Lemaître when he suggested the universe emerged from a "primeval atom".
In physical cosmology, the age of the universe is the time elapsed since the Big Bang.Astronomers have derived two different measurements of the age of the universe: a measurement based on direct observations of an early state of the universe, which indicate an age of 13.787 ± 0.020 billion years as interpreted with the Lambda-CDM concordance model as of 2021; and a measurement based on the ...
Ordinary (baryonic) matter (4.9%) Dark matter (26.8%) Dark energy (68.3%) [6] The observable universe is a ball-shaped region of the universe consisting of all matter that can be observed from Earth or its space-based telescopes and exploratory probes at the present time; the electromagnetic radiation from these objects has had time to reach ...
The universe consists of a plasma of nuclei, electrons, and photons; temperature is too low to create electron-positron pairs (or any other pairs of massive particles), but too high for the binding of electrons to nuclei. Recombination: 18 ka ~ 370 ka 6000 ~ 1100 4000 K (0.4 eV) Electrons and atomic nuclei first become bound to form neutral ...
Geocentric model. In astronomy, the geocentric model (also known as geocentrism, often exemplified specifically by the Ptolemaic system) is a superseded description of the Universe with Earth at the center. Under most geocentric models, the Sun, Moon, stars, and planets all orbit Earth.
Galaxy. NGC 4414, a typical spiral galaxy in the constellation Coma Berenices, is about 55,000 light-years in diameter and approximately 60 million light-years from Earth. A galaxy is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity.