Spin (physics) discrete angular momenta despite having no orbital angular momentum. In some ways, spin is like a vector quantity; it has a definite magnitude, and it has a "direction" (but quantization makes this "direction" different from the direction of an ordinary vector). All elementary particles of a given kind have the same magnitude of spin angular momentum, which is indicated by assigning the particle a spin quantum number. The SI unit of spin is the (N·m·s) or (kg·m·s), just as with classical angular momentum. In practice, spin is given as a dimensionless spin quantum number by dividing the spin angular momentum
Absolute magnitude local objects, a K correction might have to be applied to the magnitudes of the distant objects. The absolute magnitude can also be approximated using apparent magnitude and stellar parallax : or using apparent magnitude and distance modulus : Rigel has a visual magnitude of 0.12 and distance about 860 light-years Vega has a parallax of 0.129″, and an apparent magnitude of 0.03 Alpha Centauri A has a parallax of 0.742″ and an apparent magnitude of −0.01 The Black Eye Galaxy has a visual magnitude of 9.36 and a distance modulus of 31.06 The bolometric magnitude , takes into account