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A phenomenon occurring when a discrete double-excitation state of an atom lies in the ground-state continuum. In the autoionization process one of the excited electrons is ejected, leaving the ion in an excited state (see dielectronic recombination; see also Auger effect). (also called pre-ionization.)
Industry:Astronomy
1) A measure of the intrinsic brightness of a star or galaxy. Absolute magnitude is defined as the apparent magnitude the star or galaxy would have if it were 32.6 light-years (10 parsecs) from Earth. The lower an object's absolute magnitude, the greater its intrinsic brightness. For example, the Sun has an absolute magnitude of +4.83, while Sirius, whose intrinsic brightness is greater, has an absolute magnitude of +1.43. A star that is one absolute magnitude brighter than another (e.g., +4 versus +5) is 2.5 times intrinsically brighter; a star that is 5 absolute magnitudes brighter is 100 times intrinsically brighter; and a star that is 10 absolute magnitudes brighter is 10000 times intrinsically brighter.
2) The absolute magnitude (g) of a solar-system body such as an asteroid is defined as the brightness at zero phase angle when the object is 1 AU from the Sun and 1 AU from the observer.
Industry:Astronomy
Temperature measured on the Kelvin scale: 0 Kelvin = -273.15 degree Celsius. Absolute temperature is directly related to (kinetic) energy via the equation E = kBT, where kB is Boltzmann's constant. So, a temperature of 0 K corresponds to zero energy, and room temperature, 300 K = 27 degree, corresponds to an energy of 0.025 eV.
Industry:Astronomy
The number of atoms in 12 grams of carbon 12. The number of atoms in a gram-atom (mass in grams numerically equal to the atomic weight) or the number of molecules in a gram-molecule (mass in grams numerically equal to the molecular weight.)
Industry:Astronomy
1) An eclipsing system of at least three components (B8 V, K0, Am). Period of components A and B is about 68.8 hours; period of components A, B, and C is about 1.9 years. Long term observations also indicate a massive, unseen fourth component with a period of about 190 years. Algol is also an erratic radio source of about 0.5 AU diameter.
2) The most famous eclipsing binary, Algol was probably the first variable star discovered. It lies in the constellation Perseus and consists of two stars that orbit each other every 2.87 days. When one star passes in front of the other, the light of the system dims.
Industry:Astronomy
Star galoppante che diverge da una zona relativamente piccola nel Orion.
Industry:Astronomy
1) във физиката на Аристотел, Петият елемент, от който са изработени звездите и планетите.
2) в класическата физика, невидими носител, който е смятало да разстилам всички пространство.
Industry:Astronomy
Изкуството на привеждане части на Вселената, перфектно състояние, към които те са смятани за aspire - например, злато за метали, безсмъртието за човешки същества.
Industry:Astronomy
