Search results
Results from the WOW.Com Content Network
In astronomy, a period-luminosity relation is a relationship linking the luminosity of pulsating variable stars with their pulsation period. The best-known relation is the direct proportionality law holding for Classical Cepheid variables , sometimes called the Leavitt Law .
In astronomy, values for luminosity are often given in the terms of the luminosity of the Sun, L ⊙. Luminosity can also be given in terms of the astronomical magnitude system: the absolute bolometric magnitude ( M bol ) of an object is a logarithmic measure of its total energy emission rate, while absolute magnitude is a logarithmic measure ...
In astronomy, surface brightness (SB) quantifies the apparent brightness or flux density per unit angular area of a spatially extended object such as a galaxy or nebula, or of the night sky background. An object's surface brightness depends on its surface luminosity density, i.e., its luminosity emitted per unit surface area.
Luminous blue variable AG Carinae as seen by the Hubble Space Telescope. Luminous blue variables (LBVs) are rare, massive and evolved stars that show unpredictable and sometimes dramatic variations in their spectra and brightness.
The CIE 1924 photopic V(λ) luminosity function, [cie 3] which is included in the CIE 1931 color-matching functions as the y (λ) function, has long been acknowledged to underestimate the contribution of the blue end of the spectrum to perceived luminance.
A U.S. judge overseeing an auction of shares in the parent of Venezuela-owned Citgo Petroleum on Monday agreed to reopen a data room to allow potential buyers to prepare new bids, a court document ...
By Simon Lewis (Reuters) -The Biden administration is concerned that a weakened Iran could build a nuclear weapon, White House National Security Adviser Jake Sullivan said on Sunday, adding that ...
is buying Shutterstock to create a $3.7 billion visual content company. “With the rapid rise in demand for compelling visual content across industries, there has never been a better time for our ...