Subdwarf O star

"SdO" redirects here. For other, see SDO (disambiguation).
Schematic cross-section of an O-type subdwarf.

A subdwarf O star (sdO) is a type of hot, but low-mass star. O-type subdwarfs are much dimmer than regular O-type main-sequence stars, but with a brightness about 10 to 100 times that of the Sun,[1] and have a mass approximately half that of the Sun. Their temperature ranges from 40,000 to 100,000 K. Ionized helium is prominent in their spectra. Gravity acceleration is expressed by log g between 4.0 and 6.5.[2] Many sdO stars are moving at high velocity through the Milky Way and are found at high galactic latitudes.[3]

  1. ^ Napiwotski, Ralf. "The Origin of Helium Rich Subdwarf O Stars" (PDF). Retrieved 9 June 2011.
  2. ^ Rey, Raquel Obeiro. "Asterosismology of Hot Subdwarf Stars" (PDF). Retrieved 9 June 2011.
  3. ^ Cite error: The named reference viotti was invoked but never defined (see the help page).