Facts about Mizar
- 09
Named in ancient Arabic astronomical tradition, Mizar corresponds to the word for 'groin' or 'loin,' referring to its position in the figure of the Great Bear constellation.
- 08
Mizar A's spectrum displays distinctive hydrogen and helium absorption lines characteristic of an A-type main-sequence star with a surface temperature around 9,200 Kelvin.
- 07
Within Mizar's hierarchical quadruple system, the inner binary pair Mizar Aa and Mizar Ab complete an orbit every 20.5 days while remaining gravitationally bound to their wider companion Mizar B.
- 06
Spectroscopic analysis reveals that Mizar A contains at least two stars orbiting each other with a period of 20.5 days, making the system a hierarchical quadruple star arrangement rather than a simple binary.
- 05
Approximately 5.2 million years ago, Mizar A and Mizar B were likely formed together in the same stellar nursery, sharing similar chemical compositions and ages within the same star system.
- 04
Mizar A, the primary star in the system, is approximately 2.65 times more massive than our Sun and shines roughly 230 times brighter.
- 03
Alcor, Mizar's naked-eye companion star, orbits the primary system with a period of approximately 500,000 years, making it one of astronomy's widest and slowest binary pairs.
- 02
Located approximately 88 light-years from Earth, Mizar serves as the naked-eye visual binary in the Big Dipper's handle, separating into two distinct stars when viewed through a telescope.
- 01
The four-star system Mizar contains a spectroscopic binary pair discovered in 1889, making it one of astronomy's first identified binary stars.