Life & Death of Stars: Stellar Evolution Radiation Quiz

If a Sun-like star exhausts the hydrogen in its core, then the core contracts and the outer layers expand and cool; if the star expands and cools, then it becomes a Red Giant.

If a star is more massive, then its core pressure and temperature are higher; if the temperature is higher, then it emits more high-energy photons, which are categorized as UV radiation.

If a star is in the main sequence, then it is in hydrostatic equilibrium; if it is in equilibrium, it must be fusing hydrogen into helium in its core to provide outward pressure.

If gravity causes a massive cloud of interstellar gas and dust to collapse, then a star begins to form; if such a cloud exists, it is scientifically termed a nebula.

If a star has a very high surface temperature (over 30,000 K), then according to Wien's Law, its peak emission shifts to shorter wavelengths; if it shifts to shorter wavelengths, it emits blue and UV light.

If a star is high-mass (over 8 solar masses), then it undergoes a supernova; if it undergoes a supernova, the remaining core will collapse into either a neutron star or a black hole.

If a low-to-medium mass star sheds its outer layers as a planetary nebula, then the remaining carbon-oxygen core is left behind; if that core is exposed, it is known as a white dwarf.

If a white dwarf has no fusion, gravity tries to collapse it; if the electrons are packed so tightly they cannot occupy the same state, then they create "electron degeneracy pressure" to halt the collapse.

If gravity is so strong that the escape velocity exceeds the speed of light, then there is a point of no return; if such a point exists, it is defined as the event horizon.

If a star fuses heavier elements, it gains energy until it reaches iron; if iron is fused, it consumes energy rather than releasing it; if energy is consumed, the core collapses instantly.

If UV radiation and stellar winds from young stars hit a nearby nebula, then they compress the gas; if the gas is compressed, gravity can take over and initiate the birth of new stars.

If gravity and fusion rates are determined by the amount of matter present, then the initial mass is the single variable that dictates how fast a star burns and how it will die.

If a supernova core is between 1.4 and 3 solar masses, then gravity crushes atoms until protons and electrons combine; if this happens, the resulting object is a neutron star.

If a massive star's core collapses, it triggers a shockwave; if a shockwave occurs, it creates heavy elements and a massive burst of light, leaving behind a compact remnant.

If a protostar is still relatively cool and shrouded in dust, then its peak emission is in the infrared; if an O-type star is much hotter, then the O-type star emits significantly more UV.

If a red giant loses its outer layers due to thermal pulses, then those layers expand into space; if these gas layers are ionized by the hot core, they glow as a planetary nebula.

If a star is stable and not changing size, then the forces of gravity and pressure must be equal; if these forces are equal, the star is in hydrostatic equilibrium.

If a high-mass star has more fuel but uses it at an exponentially faster rate due to extreme core pressure, then it will exhaust its fuel and die much sooner than a smaller star.

If a star must have a remaining core mass of over 3 times the Sun's mass to become a black hole, and if the Sun is only 1 solar mass total, then the Sun lacks the mass required to ever become a black hole.

If hot stars emit UV photons, then those photons strip electrons from surrounding hydrogen gas; if the gas is ionized, it is called an H II region, which is best detected via UV and radio data.