The tables below list the world's most densely populated countries, both in absolute terms and in comparison to their total populations.Population density (people per km2) map of the world in 1994. Re ...
Six of Earth's seven continents are permanently inhabited on a large scale. Asia is the most populous continent, with its 4.3 billion inhabitants accounting for 60% of the world population. The world' ...
In the earliest works of science, a species was simply an individual organism that represented a group of similar or nearly identical organisms. No other relationships beyond that group were implied. ...
A usable definition of the word "species" and reliable methods of identifying particular species is essential for stating and testing biological theories and for measuring biodiversity. Traditionally, ...
To reflect the minimum phenomena required, other biological definitions of life have been proposed, many of these are based upon chemical systems. Biophysicists have commented that living things funct ...
Astronomical objects or celestial objects are naturally occurring physical entities, associations or structures that current science has demonstrated to exist in the observable universe. The term astr ...
All terrestrial planets have approximately the same type of structure: a central metallic core, mostly iron, with a surrounding silicate mantle. The Moon is similar, but has a much smaller iron core. ...
90377 Sedna (520 AU average) is a large, reddish object with a gigantic, highly elliptical orbit that takes it from about 76 AU at perihelion to 940 AU at aphelion and takes 11,400 years to complete. ...
For many thousands of years, humanity, with a few notable exceptions, did not recognize the existence of the Solar System. People believed Earth to be stationary at the centre of the universe and cate ...
The SI unit for density is:kilograms per cubic meter (kg/m3)Litres and metric tons are not part of the SI, but are acceptable for use with it, leading to the following units:kilograms per liter (kg/L) ...
Hesiod's Theogony tells how, after Chaos, "wide-bosomed" Gaia (Earth) arose to be the everlasting seat of the immortals who possess Olympus above, and the depths of Tartarus below (as some scholars in ...
Astronomy Earth or Terra in Latin and other languagesTerra (satellite), a multi-national NASA scientific research satelliteTerrae as extensive land masses found on various solar system bodiesList of t ...
The snapshot—taken by astronauts on December 7, 1972, at 5:39 a.m. EST (10:39 UTC)—is one of the most widely distributed photographic images in existence. The image is one of the few to show a fully ...
Mythological cosmologies often depict the world as centered around an axis mundi and delimited by a boundary such as a world ocean, a world serpent or similar. In some religions, worldliness (also cal ...
The MCS is the fourth longitudinal birth cohort study conducted in the UK. Its aim is to create a multi-purpose dataset that describes the diversity of backgrounds into which children are born in the ...
