Which of the following statements is true of the Chandrasekhar limit?
A) A star more massive than 1.4 solar masses cannot become a white dwarf unless it gets rid of the extra mass in some way.
B) Mathematical models predict that degenerate electron pressure can only support objects with more than 1.4 solar masses.
C) White dwarfs contain a tremendous amount of heat, but they need only few years to radiate that heat.
D) Stars that begin life with as much as 8 solar masses cannot collapse to form white dwarfs because they do not lose mass.
Question 2
In the context of star clusters, which of the following statements is true of the turnoff point?
A) It is the point on the main sequence of a Hertzsprung-Russell diagram that is used to determine the luminosity class of the stars in the cluster.
B) Stars at this point are considered to have just taken birth and have 90 percent of their life remaining.
C) The life expectancy of the stars at this point is not equivalent to the age of the cluster.
D) It is the point on the main sequence of a Hertzsprung-Russell diagram where stars evolve to the right of the H-R diagram to become giants.
Betelgeuse is a semiregular variable star
A white dwarf star in orbit around Sirius (artist's impression)
Internal structures of main sequence stars, convection zones with arrowed cycles and radiative zones
True Friendship
Adapoids and omomyoids had longer snouts and are the first “true” primates.
Florometra Crinoid or Feather Star, Phylum Echinodermata. Monterey Canyon, California.