A star who's brightness changes is called a variable star.
Examples are:
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A variable star (or pulsating star) is a star that an earth observer sees as changing in luminosity over time. This variation in brightness may be something the star is "doing itself" because of changes in its nucleosynthetic processes, or it may be due to the passage of dust clouds or the like between the star and the observer. Wikipedia has more information, and you'll find a link to their post below.
An apparent brightness is the brightness of a star as measured by an observer.
Magnitude refers to the brightness of a star. There are two main types: apparent magnitude, which is how bright a star appears from Earth, and absolute magnitude, which measures a star's intrinsic brightness.
A pulsating star is a type of variable star that changes in brightness due to periodic expansions and contractions of its outer layers. These changes can be regular or irregular, and the star's size and temperature vary over time. Examples of pulsating stars include Cepheid variables and RR Lyrae stars.
Its magnitude.
A variable star is a star whose brightness as seen from Earth that fluctuates.
A variable star is a star whose brightness as seen from Earth that fluctuates.
A decrease in a star's absolute brightness could be caused by the star moving farther away from Earth, interstellar dust blocking some of its light, or a decrease in the star's temperature. All of these factors would result in less light reaching Earth, causing a decrease in the star's apparent brightness.
A variable star (or pulsating star) is a star that an earth observer sees as changing in luminosity over time. This variation in brightness may be something the star is "doing itself" because of changes in its nucleosynthetic processes, or it may be due to the passage of dust clouds or the like between the star and the observer. Wikipedia has more information, and you'll find a link to their post below.
the brightness of a star
The measure of a star's brightness is its magnitude. A star's brightness as it appears from Earth is called its Apparent Magnitude.Star's brightness is measured by there magnitude.
photographs use to measure the brightness of a star
The brightness as seen from Earth is called the "apparent magnitude".The real brightness (defined as the apparent brightness, as seen from a standard distance) is called the "absolute magnitude".
Well, I got a couple that I can think of off the top of my head Venus - Planet Virgo - Constellation Variable Star - A star whose brightness changes periodically Van Allen Belts - Radiation/Groups of charged particles that surround the Earth
There is no purpose of a star's brightness. They just exist and shine.
brightness and temperature are both related because brightness is actually tempature. However the system has become more refined. Instead of just looking at the star and determining magnitude one or magnitude two, an astronomer measures the brightness of the star using a device called a photometer. The photometer counts the number of photons coming from the star. This photon count is then compared to the photon count from a star whose magnitude is known. An accurate magnitude can then be calculated.
An apparent brightness is the brightness of a star as measured by an observer.