Enter the flux in watts per square meter and the distance in parsecs into the calculator to determine the luminosity in watts. This calculator helps in understanding the intrinsic brightness of celestial objects.
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Flux To Luminosity Formula
The following formula is used to calculate the luminosity of an object based on its observed flux and distance:
L = 4 * π * d^2 * F
Variables:
- L is the luminosity (watts)
- F is the observed flux (watts per square meter)
- d is the distance from the object (parsecs)
To calculate the luminosity, multiply the observed flux by 4π and then by the square of the distance in meters.
| Flux (W/m²) | Distance | Luminosity (L☉) |
|---|---|---|
| 13.6 | 1 AU | 0.01 |
| 136 | 1 AU | 0.1 |
| 1.36e3 | 1 AU | 1 |
| 1.36e4 | 1 AU | 10 |
| 3.20e-10 | 1 pc | 0.01 |
| 3.20e-9 | 1 pc | 0.1 |
| 3.20e-8 | 1 pc | 1 |
| 3.20e-7 | 1 pc | 10 |
| 3.20e-12 | 10 pc | 0.01 |
| 3.20e-11 | 10 pc | 0.1 |
| 3.20e-10 | 10 pc | 1 |
| 3.20e-9 | 10 pc | 10 |
| 3.20e-16 | 1 kpc | 0.01 |
| 3.20e-15 | 1 kpc | 0.1 |
| 3.20e-14 | 1 kpc | 1 |
| 3.20e-13 | 1 kpc | 10 |
| 3.20e-22 | 1 Mpc | 0.01 |
| 3.20e-21 | 1 Mpc | 0.1 |
| 3.20e-20 | 1 Mpc | 1 |
| 3.20e-19 | 1 Mpc | 10 |
| * Values rounded to 3 significant figures. Uses L = 4π d² F. Constants: L☉ = 3.828×10²⁶ W; 1 AU = 1.495978707×10¹¹ m; 1 pc = 3.085677581491367×10¹⁶ m; 1 kpc = 10³ pc; 1 Mpc = 10⁶ pc. | ||
What is Luminosity?
Luminosity is the total amount of energy emitted by an object, such as a star or galaxy, per unit of time. It is an intrinsic property that does not depend on the object's distance from the observer. Luminosity is a fundamental parameter used in astronomy to understand the nature and evolution of celestial bodies.
How to Calculate Luminosity?
The following steps outline how to calculate the Luminosity.
- First, determine the observed flux (F) in watts per square meter.
- Next, determine the distance from the object (d) in parsecs.
- Convert the distance from parsecs to meters (1 parsec = 3.0857e+16 meters).
- Use the formula L = 4 * π * d^2 * F to calculate the luminosity (L) in watts.
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
observed flux (F) = 3.2e-12 watts per square meter
distance from the object (d) = 100 parsecs
