Astronomy 101 - Stellar Remnants Quiz

How does a nova from a white dwarf differ from a supernova from a white dwarf or a massive star?

A nova from a white dwarf results in a surface explosions, but a supernova from a white dwarf or massive star will result in the destroyed star. A white dwarf nova occurs when the star "steals" gas from nearby, triggering an explosion when the gas collects on the surface. Meanwhile supernova is divided into two types, type Ia and type II. Type Ia supernova is when the star "steals" gas from nearby and once it gathers enough together is causes a thermonuclear blast which destroys the star. Type II supernova is when the star can no longer create nuclear energy in its core so it eventually collapses into a neutron star or a black hole due to the gravity.

What keeps white dwarfs and neutron stars from collapsing? A. Degeneracy pressure, a quantum mechanical phenomenon. It is the electrons in the white dwarf and the neutrons in the neutron star which cannot be squeezed any tighter. B. Their incredibly high densities make them very hard . C. The dark energy they contain. D. Pressure from the hot core.

A. Degeneracy pressure, a quantum mechanical phenomenon. It is the electrons in the white dwarf and the neutrons in the neutron star which cannot be squeezed any tighter.

When a star of mass less than 8 solar masses reaches the end of its life it becomes A. a white dwarf B. a black hole C. a neutron star D. A Wolf-Reyete star

A. a white dwarf

An object more massive than the sun, but roughly the size of a city is a A. neutron star B. supernova remnant C. white dwarf D. red dwarf E. brown dwarf

A. neutron star

How did we first detect the merger of black holes? A. by direct optical imaging. B. Gravity waves C. the bright flash of light given off. D. By the giant sucking sound.

B. Gravity waves

You would expect millisecond pulsars to be A. rotating slowly B. isolated in space C. part of a binary system D. collapsing rapidly E. most common in open clusters

C. part of a binary system

What stellar remnant is about the size of Earth? A. Red dwarf. B. Black hole C. Neutron star D. White dwarf

D. White dwarf

Two important properties of a young neutron star are A. extremely slow rotation and a strong magnetic field B. no rotation and no magnetic field C. extremely rapid rotation and a weak magnetic field D. extremely rapid rotation and a strong magnetic field E. extremely slow rotation and a weak magnetic field

D. extremely rapid rotation and a strong magnetic field

What events create elements more massive than iron ? A. fusion in the core of very massive stars. B. black hole mergers. C. mergers of neutron stars D. supernova shock waves

Select - C. mergers of neutron stars D. supernova shock waves

The figure below shows two light curves, one for type II and one for type Ia supernovae. The curve which indicates a type Ia supernova is __________________, The long shoulder on the red curve is due to ___________________. Space 1 options - A. The red curve B. The green curve C. Possibly either curve Space 2 options - A. Fusion in the shockwave from the supernova explosion. B. The last fusion stage of the stellar core. C. Hot gas spreading out from the star making it larger and more luminous.

Space 1 answer - B. The green curve Space 2 answer - A. Fusion in the shockwave from the supernova explosion.

Which type of supernova, type II or type Ia, has few, if any, hydrogen lines? Why is this the case?

The type II supernova show hydrogen lines. Type II are generally lower mass stars, which is why they are more likely to have hydrogen present. The larger mass stars could have had their hydrogen blown off by strong stellar winds by the time of the explosion which would create the supernova. This is why type II supernova, generally smaller in mass, show hydrogen over the type Ia supernova. Type Ia superovae are white dwarfs exploding; they have no hydrogen left.