Mira

This is a picture of Mira taken by the Hubble Space Telescope.

Mira is a binary star system with a white dwarf (Mira B, also known as VZ Ceti) star and a red giant (Mira A). Scientists think Mira is 200-400 light years away in the constellation Cetus. Mira A is a variable star, changing its size and brightness. Other red giant stars that do the same are called Mira variables.

Mira changes brightness cyclically

Size

Mira has a diameter 332^[1] to 541^[2] times that of our sun.

If Mira's size was constant, then its diameter would be only 240 times larger than the Sun.^[1]

Mira Media

Mira at two different times
Mira as seen from the Earth
Mira in UV and visible light
Pulsations in χ Cygni, showing the relation between the visual light curve, temperature, radius and luminosity typical of Mira variable stars
Ultraviolet mosaic of Mira's bow shock and tail obtained using NASA's Galaxy Evolution Explorer (GALEX)

Related pages

References

↑ ^1.0 ^1.1 Wood, P. R.. Interferometric observations of the Mira star o Ceti with the VLTI/VINCI instrument in the near-infrared. Astronomy & Astrophysics 421 (2) (1 July 2004). p. 703–714. doi:10.1051/0004-6361:20035826.
↑ Menten, K. M.. Probing the mass-loss history of AGB and red supergiant stars from CO rotational line profiles - II. CO line survey of evolved stars: derivation of mass-loss rate formulae. Astronomy & Astrophysics 523 (1 November 2010). p. A18. doi:10.1051/0004-6361/200913771.

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[auto-1] 1.0 ^1.1 Wood, P. R.. Interferometric observations of the Mira star o Ceti with the VLTI/VINCI instrument in the near-infrared. Astronomy & Astrophysics 421 (2) (1 July 2004). p. 703–714. doi:10.1051/0004-6361:20035826.

[2] Menten, K. M.. Probing the mass-loss history of AGB and red supergiant stars from CO rotational line profiles - II. CO line survey of evolved stars: derivation of mass-loss rate formulae. Astronomy & Astrophysics 523 (1 November 2010). p. A18. doi:10.1051/0004-6361/200913771.

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