From Wikipedia, the free encyclopedia. This article is about a branch of knowledge. For other uses, see Science (disambiguation). Science (from the Latin word scientia, meaning "knowledge")[1] is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.[2][3][4] The earliest roots of science can be traced to Ancient Egypt and Mesopotamia in around 3500 to 3000 BCE.[5][6] Their contributions to mathematics, astronomy, and medicine entered and shaped Greek natural philosophy of classical [...]


Outer space, or simply space, is the expanse that exists beyond Earth and between celestial bodies. Outer space is not completely empty—it is a hard vacuum containing a low density of particles, predominantly a plasma of hydrogen and helium, as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays. The baseline temperature of outer space, as set by the background radiation from the Big Bang, is 2.7 kelvins (−270.45 °C; −454.81 °F).[1] The plasma between galaxies accounts for about [...]

Space Exploration

Space exploration From Wikipedia, the free encyclopediaJump to navigationJump to search"Space Exploration" redirects here. For the company, see SpaceX.Humans explore the lunar surfaceThis Kuiper belt object, known as Ultima Thule, is the farthest closely visited Solar System body, seen in 2019 Space exploration is the use of astronomy and space technology to explore outer space.[1] While the exploration of space is carried out mainly [...]