The magnitude a star would have if it were at a distance of 10 parsecs in a void space, without interstellar absorption. The absolute magnitude is usually deduced from the visual magnitude, measured t
hrough a V filter (UBV system), when it is written as M_V. If it is defined for another wavelength, it gets another index (U, B, etc). If the radiation on all wavelengths is included, it becomes absolute bolometric magnitude, M_bol. The Sun has the absolute magnitude +4.8. Most of the stars have absolute magnitudes ranging between -9 (supergiants) and +19 (red dwarfs).
A method of synchronizing a wave research facility data acquisition system and project instrument data streams using timestamps generated by the data acquisition system.
In spectroscopy, and in particular the solar Fraunhofer spectrum, a characteristic wavelength of emitted radiation that is partially absorbed by the medium between the source and the observer.