One might quickly conclude that black holes don't belong on HR diagrams since the latter is designed for stars, and black holes generally aren't considered stars. Further, given that a spectral type would be necessary to plot any given entity on an HR diagram, a black hole would have to have such typification, which it does not have - given that, due to relativistic effects, it emits no significant light. If it were assigned a spectral type, it would still need to have an agreed-upon absolute magnitude, which some might argue was "infinite" for the same reason - reflecting the observer's inability to detect any (intrinsic) light. It is, however, generally accepted that black holes emit a kind of black-body radiation owing to quantum effects (Hawking radiation) for a temperature that may vary with its surface gravity. Even if a consensus could be built regarding its luminosity and its spectral type, its presence on an HR diagram may not be 'useful,' despite its significance in theories of stellar evolution to which the HR diagram so abundantly contributes.
The Hertzsprung--Russell diagram is a scatter graph of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their spectral types or classifications and effective temperatures.Because the luminosity is low or non existent in the case of black holes, they do not appear on the HR diagram.
The Hertzsprung--Russell diagram is a scatter graph of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their spectral types or classifications and effective temperatures.Because the luminosity is low or non existent in the case of black holes, they do not appear on the HR diagram.
The Sun is classified as a G-type main-sequence star (G dwarf) on the Hertzsprung-Russell (HR) diagram. It has a surface temperature of about 5,500 degrees Celsius and an absolute magnitude of approximately +4.83. On the HR diagram, the Sun is located in the middle of the main sequence, where it occupies a position indicative of its mass and luminosity relative to other stars.
its located somewhere
The location on the Hertzsprung-Russell (HR) diagram where most stars lie is known as the main sequence. The HR diagram is a plot of stellar luminosity against surface temperature. The main sequence is a prominent band that extends diagonally across the HR diagram from high temperature and high luminosity to low temperature and low luminosity. The majority of stars, approximately 90% of all stars, are situated along the main sequence on the HR diagram. These stars are often referred to as main-sequence stars. They exhibit a smooth relationship between surface temperature and luminosity, with varying sizes and masses but sharing this common characteristic of lying on the diagonal band from the upper left to the lower right of the HR diagram. Source: Teach Astronomy - The Hertzsprung-Russell Diagram
Black holes dont appear on HR diagrams because HR diagrams are used to classify stars not find black holes Black holes emit no visible light (are not luminous enough) and therefore do not appear in the HR diagram.
The Hertzsprung--Russell diagram is a scatter graph of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their spectral types or classifications and effective temperatures.Because the luminosity is low or non existent in the case of black holes, they do not appear on the HR diagram.
The Hertzsprung--Russell diagram is a scatter graph of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their spectral types or classifications and effective temperatures.Because the luminosity is low or non existent in the case of black holes, they do not appear on the HR diagram.
Of course they are on the HR diagram. They are simply not on the main sequence.
The HR diagram contains only stars - so everywhere.
HR diagram
The red dwarves.
Up at the top right. If you look on the Australian Telescope National facility website, their HR diagram shows this clearly.
The main reason that the HR Diagram is so useful and important to scientists is, you can tell the size of the star by plotting it on the HR Diagram. The different sizes of stars form a pattern on the HR diagram.
its located somewhere
All stars.
Slightly to the right of centre on the main sequence. If you look on the Australian Telescope National facility website, their HR diagram shows the position of the sun.