Absolute magnitude: they are extremely bright. Temperature: their surface temperature is fairly low.
The star with the greatest absolute magnitude is typically a supergiant star, such as a blue supergiant like Rigel or a red supergiant like Betelgeuse. These stars can have absolute magnitudes of around -6 to -12, depending on their size and luminosity. In contrast, the absolute magnitude of our Sun is about +4.83, illustrating the immense brightness of supergiants compared to other stars. Generally, more massive stars tend to have more negative absolute magnitudes, indicating higher luminosity.
The absolute magnitude of a star depends on the size and temperature; a large cooler star can generate as much light as a small very hot star.
The brightness of a star depends on its temperature, size and distance from the earth. The measure of a star's brightness is called its magnitude. Bright stars are first magnitude stars. Second magnitude stars are dimmer. The larger the magnitude number, the dimmer is the star.The magnitude of stars may be apparent or absolute.
That is called the Hertzsprung-Russell or HR diagram and each star occupies a point. The horizontal axis is temperature and the vertical axis is the absolute magnitude.
Rigel is the brightest star in the constellation Orion.It has an apparent magnitude of 0.18 and an absolute magnitude of -6.7
This probably refers to red dwarves. The apparent magnitude depends on the distance, as well as the absolute magnitude, but even the closest red dwarves can't be seen with the naked eye.
Constellations don't have an absolute magnitude. That is a property of individual stars.
The graph that shows the relationship between a star's absolute magnitude and temperature is called the Hertzsprung-Russell (H-R) diagram. In this diagram, stars are plotted according to their absolute magnitude (or luminosity) on the vertical axis and their surface temperature on the horizontal axis. Typically, the temperature decreases from left to right, and the diagram reveals distinct regions for different types of stars, including main sequence stars, giants, and white dwarfs. This allows astronomers to classify stars and understand their evolutionary stages.
Absolute magnitude and surface temperature
Its called an HR diagram or a Hertzsprung-Russell diagram.
The question is: Why is the apparent magnitude of some stars less than their absolute magnitude. Or: Why do some stars not look as bright as they really are ? The answer is: Because they're so far away from us.
preallax