Rohan1997 said:Do two stars of the same absolute bolometric magnitude have the same absolute visual magnitude?
If this is true; does this mean that two stars with the same power output have the same have the same bolometric magnitude and therefore same visual magnitude?
virgil1612 said:When you say bolometric, it's about the radiation emitted at all wavelengths. Visual absolute magnitude, it's about the radiation emitted in the visible part of the spectrum. So you could have stars so hot that they emit the most of their radiation in the UV; for them, the bolometric magnitude would be much bigger than the visual magnitude. In the same way, cool stars would produce most of their radiation in the infrared and again, they would be barely visible (small absolute visual magnitude). It all depends on the surface temperature of the star.
Absolute magnitude is a measure of the intrinsic brightness of a celestial object, regardless of its distance from Earth. It is defined as the apparent magnitude that the object would have if it were located at a distance of 10 parsecs (32.6 light years) from Earth.
Apparent magnitude is a measure of how bright an object appears to be from Earth. It takes into account both the intrinsic brightness of the object and its distance from Earth. Absolute magnitude, on the other hand, only measures the intrinsic brightness of an object.
By knowing the absolute magnitude of an object, we can calculate its luminosity using the inverse square law. This law states that the brightness of an object is inversely proportional to the square of its distance. So, if we know the absolute magnitude and distance of an object, we can determine its luminosity.
Absolute magnitude only takes into account the visible light emitted by an object, while bolometric magnitude measures the total amount of energy emitted by an object across the entire electromagnetic spectrum. This means that bolometric magnitude takes into account all wavelengths of light, including infrared and ultraviolet, while absolute magnitude only considers visible light.
Absolute magnitude is important because it allows us to compare the intrinsic brightness of celestial objects. This is useful for understanding the true nature of these objects, as well as for determining their distances and other important properties. It also helps us to classify objects based on their luminosity, which can provide insights into their evolution and lifespan.