BO Microscopii

Stellar classification



  • X -13
  • Y -91
  • Z 112
→ Sol: 145

Object type

  • Variable of BY Dra type
  • Star
  • Infra-Red source
  • Pre-main sequence Star
  • UV-emission source
  • Variable Star
  • X-ray source
simbad:V* BO Mic


BO Microscopii (BO Mic) is a star in the constellation Microscopium located about 170 light years from the Sun. It has been dubbed "Speedy Mic" because of the ultra-rapid rotation rate. The projected rotational velocity at the equator of this star is about 135 km/s, which, with an estimated inclination of 70° to the line of sight from the Earth, means it completes a rotation every 0.380 ± 0.004 days (9 hours 7 minutes). The photosphere of this star shows a high level of magnetic activity, with multiple star spots and prominences observed at the same time. As many as 25 prominences have been observed simultaneously, extending outward as far as 3.6 times the radius of the star. BO Mic is a flare star that undergoes sudden increases in X-ray and ultraviolet emissions. These events can emit a hundred times more energy than large solar flares. Speedy Mic is one of the most active stars in the vicinity of the Sun.

This article uses material from the Wikipedia article "BO Microscopii", which is released under the Creative Commons Attribution-Share-Alike License 3.0.