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18 Φεβ 2016 · Table A5 contains many colours for stars as a function of spectral type. You need to combine this with something that gives absolute V magnitude along the main sequence, like that of Schmidt-Kaler (1982).
In astronomy, magnitude is a measure of the brightness of an object, usually in a defined passband. An imprecise but systematic determination of the magnitude of objects was introduced in ancient times by Hipparchus. Magnitude values do not have a unit.
With the invention of the telescope and modern equipment to measure star magnitudes the scale has been extended in both directions. Dimmer stars are assigned magnitudes larger than 6 ( 6, 7, 8, 9, ... 30th ... etc.) The Hubble Space Telescope Deep Field image contains some galaxies as faint as 30th magnitude.
In principle, to see the wavelength distribution of the emission from a star (i.e. spectrum), a spectrogram is required. However, it is more difficult to get the spectrum of a star. It requires a larger telescope. It would be easier to compare the magnitudes of different wavelength bands.
A star's magnitude is a measure of how that star's brightness compares to the brightness of other stars, and that is how one measure a star's magnitude: by comparing it to the magnitude of another star. It is measured this way because of the difficulty of measuring the power received from a star.
7 Νοε 2024 · Absolute Magnitude. The inherent brightness, or intensity of a star, as seen to the naked eye on Earth, depends on its: Luminosity. Distance from Earth. If two different stars have the same apparent magnitude it does not necessarily mean they emit the same amount of light or are the same size
This diagram shows most of the major types of stars. The vast majority of stars are main sequence stars - these are star like the Sun that are burning hydrogen into helium to produce their energy. Most stars spend 90% of their life as main sequence stars.
