Browse Reference Articles
31 to 40 of 113 articles
-
Solar radiation
Solar radiation is radiant energy emitted by the sun, particularly electromagnetic energy. About half of the radiation is in the visible short-wave part of the electromagnetic spectrum. The other ... > more -
Carl Sagan
Dr Carl Edward Sagan (November 9, 1934 - December 20, 1996) was an American astronomer, astrobiologist and highly successful science popularizer. He pioneered exobiology and promoted the Search for ... > more -
Jupiter's natural satellites
Jupiter has 63 known natural satellites. Although claims are made for the observation of one of Jupiter's moons by Chinese astronomer Gan De in 364 BC, the first certain observations of Jupiter's ... > more -
Extraterrestrial life
Extraterrestrial life is life that may exist and originate outside the planet Earth, the only place in the universe currently known by humans to support life. Its existence is currently purely ... > more -
Definition of planet
The definition of "planet" has for some time been the subject of intense debate. Although the word dates back thousands of years, no officially decreed scientific definition of "planet" existed ... > more -
Saturn's natural satellites
Saturn is currently known to have 56 moons, many of which were discovered very recently, and 3 additional un-confirmed, hypothetical moons. However, a precise number of moons can never be given, as ... > more -
Eris (dwarf planet)
Eris is the largest known dwarf planet in the solar system. It is a trans-Neptunian object (TNO), orbiting the Sun in a region of space known as the scattered disc, just beyond the Kuiper belt, and ... > more -
Ionosphere
The ionosphere is the part of the atmosphere that is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical ... > more -
Exploration of Mars
The exploration of Mars has been an important part of the space exploration missions of the Soviet Union (later Russia), the United States, Europe, and Japan. Dozens of unmanned spacecraft, including ... > more
Search ScienceDaily
Number of stories in archives: 137,221

