lifecycle

Question 1

• large dense cloud of gas and dust

Answer 1

stellar nebula

Question 2

• early stage in star formation
• forms when a region of stellar nebula collapses under gravity and heats up.
• as it grows, it gathers more material and the core gets hotter.
• core becomes hot and dense enough for nuclear fusion , birthing a new star.

Answer 2

protostar

Question 3

• stable and long-lasting phase of the lifecycle.
• fuses hydrogen to helium in its core, producing energy that makes stars shine
• like our sun
• eventually evolves into red giants as they exhaust hydrogen fuel.

Answer 3

main sequence

Question 4

• occurs when a star has exhausted most of hydrogen fuel and has begun the process of dying.
• star expands and cools, making it appear larger and redder.
• core contracts the heat up, leading to fusion of heavier elements like helium.
• large size+low surface temp
• gravity contracts core, allowing enough pressure for helium to fuse to carbon.
• outer layers drift away in shockwave, leaving the carbon core.

Answer 4

red giant

Question 5

• a region of space of cosmic gas and dust formed by the cast-off outer layers of dying stars
• outer layers drifting away

Answer 5

planetary nebula

Question 6

• stellar core that’s left behind after a dying star has exhausted its nuclear fuel
• carbon core
• maintaining energy from nuclear fusion.
• no longer fusing and won’t collapse further
• fades as energy depletes

Answer 6

white dwarf

Question 7

• small cooled remnant of white dwarf that emits no detectable light energy.
• dead star made of carbon, now cold due to loss of all remaining energy.

Answer 7

black dwarf

Question 8

• end of lifecycle and explodes in a burst of light.
• gravity causes a catastrophic collapse of the core
• iron atoms are crushed and electrons are pushed into the nuclei
• rapid increase in temp and repulsive electrical forces in the core cause a massive, bright, short-lived explosion.

Answer 8

supernova

Question 9

• region of space that has a gravitational field so intense that no matter or radiation can escape.
• product of massive stars

Answer 9

blackhole

Question 10

• formed when a massive star runs out of fuel and collapses, crushing together every proton and electron into a neutron
• remaining extremely dense core
• strong magnetic field
• rapid spin
• no fusion

Answer 10

neutron star

Question 11

• large star, extremely bright, great luminosity
• several magnitudes brighter than a giant star and several times greater in diameter
• large radius for its mass and temp
• high mass
• core under high pressure and temps
• fuses helium to iron (most stable nucleus)
• fusion stops at iron, and the star can’t release further energy from the core.

Answer 11

supergiant

Question 12

SA and temp is determined by

Answer 12

brightness and magnitude