B) blue from the scattering of light off the tiny molecules
C) blue due to ionized helium atoms
D) red due to the Hα line of hydrogen
E) red because of reddening by dust
For a white dwarf to explode entirely as a Type I supernova, its mass must be
A) at least 0.08 solar masses.
B) 1.4 solar masses, the Chandrasekhar limit.
C) 3 solar masses, the Schwartzschild limit.
D) 20 solar masses, the Hubble limit.
E) 100 solar masses, the most massive known stars.
Which common gas is less abundant in the top of Saturn’s atmosphere, compared to
what we observe at Jupiter?
A) hydrogen
B) helium