Browse Reference Articles
21 to 30 of 193 articles
-
Outer space
Outer space, also simply called space, refers to the relatively empty regions of the universe outside the atmospheres of celestial bodies. Outer space is used to distinguish it from airspace (and ... > more -
Ultimate fate of the universe
The ultimate fate of the universe is a subject of study in the field of cosmology. Vying scientific theories predict whether the life of the universe is finite or infinite. Current understanding of ... > more -
Luminosity
In general physics, luminosity (more properly called luminance) is the density of luminous intensity in a given ... > more -
Cosmic microwave background radiation
In cosmology, the cosmic microwave background radiation is a form of electromagnetic radiation discovered in 1965. It has a thermal black-body spectrum which peaks in the microwave range. Most ... > more -
Orion Nebula
The Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a glowing emission nebula with a greenish hue and is situated below Orion's Belt. It is one of the brightest nebulae visible to the ... > more -
Blue supergiant
Blue supergiants are supergiant stars (class I) of spectral type O. They are extremely hot and bright, with surface temperatures of between 20,000 - 50,000 degrees Celsius. The best known example is ... > more -
Space observatory
A space observatory is any instrument in outer space which is used for observation of distant planets, galaxies, and other outer space objects. A large number of observatories have been launched into ... > more -
Edwin Hubble
Edwin Powell Hubble (November 20, 1889 - September 28, 1953) was an American astronomer, noted for his discovery of galaxies beyond the Milky Way and the cosmological redshift. Edwin Hubble was one ... > more -
Magellanic Clouds
The two Magellanic Clouds are irregular dwarf galaxies orbiting our Milky Way galaxy, and thus are members of our Local Group of galaxies.The Large Magellanic Cloud (LMC) and its neighbour and ... > more
Search ScienceDaily
Number of stories in archives: 140,690

