Apparent brightness
Definition
Apparent brightness is the measure of how bright a star appears from Earth. It depends on both the star's intrinsic luminosity and its distance from Earth.
5 Must Know Facts For Your Next Test
- Apparent brightness is measured in units of flux, typically watts per square meter.
- It follows the inverse square law, meaning that as distance increases, apparent brightness decreases proportionally to the square of the distance.
- Magnitude scale is used to quantify apparent brightness; lower magnitudes indicate brighter stars.
- Apparent brightness can be affected by interstellar dust and gas, which absorb and scatter light.
- It is different from absolute magnitude, which measures intrinsic luminosity independent of distance.
Review Questions
- What units are used to measure apparent brightness?
- How does the inverse square law relate to apparent brightness?
- What is the difference between apparent brightness and absolute magnitude?
"Apparent brightness" appears in:
Related terms
Luminosity: The total amount of energy a star emits per second in all directions.
Absolute Magnitude: A measure of a star's intrinsic brightness as it would be seen at a standard distance of 10 parsecs.
Inverse Square Law: A principle stating that a specified physical quantity or intensity decreases in proportion to the square of the distance from the source.
