True!
Apparent brightness: how bright an object - such as a star - looks to us. True brightness: how bright such an object really is. Defined as: how bright it would look at a standard distance.
Three factors that affect a star's brightness are the star's distance from earth, its age and its luminosity. The farther the star is from earth, the less bright it appears. As a star increases in age, its brightness also increases. Its brightness also depends on its luminosity, which is the amount of energy the star emits per second.
Both relate to brightness; both are measured in the same units; both are used for astronomical objects such as stars or galaxies.
The apparent brightness of stars depends on:* The distance * The actual brightness * In some cases, the brightness may be dimmed by clouds of dust and gas, between us and the distant star. In the case of Vega and Arcturus, Vega is NOT brighter than Arcturus. Their apparent magnitude (brightness) is about the same, with Arcturus perhaps being slightly brighter, depending on the source consulted. In terms of real brightness ("absolute magnitude"), Arcturus is actually brighter. When consulting numbers, please remember that smaller numbers refer to brighter objects.
To find the number of light years between two celestial objects, we first find the distance from each object to earth. If we connect the dots between Earth and the two objects, we have a triangle. We to sides lengths of that triangle (the distances between Earth and the objects), and we can measure one angle (the angle at the vertex where Earth is. This is enough information to find the distance between the objects using trigonometry (in this case, the law of cosines). Finding the distance from Earth to an object can be a bit complex. One commonly used method is to look for a pulsating star. We can figure out the absolute brightness (how bright it is without factoring in distance away) of these stars by how often they pulse. Then we can measure the apparent brightness (how bright it looks to us). We can then use both these values to find the distance to the star. (This also works for some supernovae.) Another method is to use objects that are considered to be 'standard candles'. These objects do not pulse, but we know the relationship between their absolute brightness, apparent brightness, and distance away.
remains the same, but the apparent brightness is decreased by a factor of four
Absolute Brightness: How bright a star appears at a certain distance. Apparent Brightness: The brightness of a star as seen from Earth.
Two factors that affect a star's apparent brightness are: 1.) The distance between the Earth and the star 2.) The absolute magnitude (the actual brightness) of the star Hope that helps :P
Apparent brightness: how bright an object - such as a star - looks to us. True brightness: how bright such an object really is. Defined as: how bright it would look at a standard distance.
Three factors that affect a star's brightness are the star's distance from earth, its age and its luminosity. The farther the star is from earth, the less bright it appears. As a star increases in age, its brightness also increases. Its brightness also depends on its luminosity, which is the amount of energy the star emits per second.
This has nothing to do with shape. The apparent magnitude means how bright a star looks to us. The absolute magnitude means how bright the star really is (expressed as: how bright would it look at a standard distance).
The star's real magnitude (brightness), its distance from us, and anything in between (usually dust or gas) which might absorb part of the light.
Both relate to brightness; both are measured in the same units; both are used for astronomical objects such as stars or galaxies.
With maths and light brightness.... Distance between two points...
The apparent brightness of stars depends on:* The distance * The actual brightness * In some cases, the brightness may be dimmed by clouds of dust and gas, between us and the distant star. In the case of Vega and Arcturus, Vega is NOT brighter than Arcturus. Their apparent magnitude (brightness) is about the same, with Arcturus perhaps being slightly brighter, depending on the source consulted. In terms of real brightness ("absolute magnitude"), Arcturus is actually brighter. When consulting numbers, please remember that smaller numbers refer to brighter objects.
To find the number of light years between two celestial objects, we first find the distance from each object to earth. If we connect the dots between Earth and the two objects, we have a triangle. We to sides lengths of that triangle (the distances between Earth and the objects), and we can measure one angle (the angle at the vertex where Earth is. This is enough information to find the distance between the objects using trigonometry (in this case, the law of cosines). Finding the distance from Earth to an object can be a bit complex. One commonly used method is to look for a pulsating star. We can figure out the absolute brightness (how bright it is without factoring in distance away) of these stars by how often they pulse. Then we can measure the apparent brightness (how bright it looks to us). We can then use both these values to find the distance to the star. (This also works for some supernovae.) Another method is to use objects that are considered to be 'standard candles'. These objects do not pulse, but we know the relationship between their absolute brightness, apparent brightness, and distance away.
The difference between apparent brightness and luminosity is that apparent brightness means that a star may appear to be bright, but only looks bright because of the relatively closeness a star is to earth. Luminosity is used by astronomers and refers to the power output of a star. Apparent Brightness means a star may appear to be very bright but only look that way because it is relatively close to Earth. Luminosity just refers to the power output of a star.