ch 13 Flashcards
what are cool, dense interstellar clouds in which the low temps allow hydrogen atoms to pair up into hydrogen molecules
molecular clouds
this forms when low-mass stars in their final death throes cast off their outer layers of gas, leaving behind the hot core that ejected the gas
planetary nebulae
what is a forming star that has not yet reached the point where sustained fusion can occur in its core
protostar
a high-mass star forms out of a cloud fragment that gravity forces to contract into a what
protostar
what’s the temperature for hydrogen fusion
about 100 million kelvin
what supplies the thermal energy that keeps a main-sequence star in balance
hydrogen fusion
what’s the minimum star mass
0.08
what’s the maximum star mass
150
what stars live longer: low or high mass
low mass
what stars run out of gas faster: low or high mass
high mass
what stars form the fastest
massive stars
