ch16,17,18

most stars are formed about 200 small stars

.08 stellar mass = how many stars:

about 50 stars

.5 stellar mass(Msun)= about how many stars:

white dwarf limit

1.4 solar masses(1.4 Msun) is the:

1 big ass star

150 stellar mass(Msun)= about how many stars:

about 10 large stars

2 stellar mass(Msun)= about how many stars:

super massive black hole(10E9Msun)

a human might survive the event horizon of a :

black hole

after a supernova if gravity can overcome the neutron stars degeneracy pressure then the core will collapse into a:

hydrogen shell fusion

after core shrinks from hydrogen fusion stopping, the hydrogen left around the now helium core will start fusion again in this:

solar wind

after helium fusion begins large amounts of mass will escape the red giant in:

subgiant

after hydrogen fusion stops in a low mass star, it's core begins to shrink, but it's outer layer will expand into a:

gamma ray bursts

are explosions with unimaginable power:

red giant

as the expansion of the outer layers of a low mass star continues the luminosity will increase and will eventually become a :

iron

bad news for stellar core

could be cause of gamma ray burst

binary neutron stars crashing into each other, or one into a black hole could be the cause of these:

cygnus x1 most promising candidate known for being black hole

black hole that binary neutron star with larger size than 3Msun:

carbon fusion

can be reached in high mass stars after helium fusion due to heat beating any sign of degeneracy pressure:

accretion disk

disk of mass for white dwarf companion swirls and becomes this:

infrared light

dust is less effective at blocking_____ making it possible to see stars behind a molecular cloud:

interstellar dust

elements like carbon, silicon, oxygen, and iron are found in tiny, solid grains of:

supernova remnent

expanding cloud of debris from a supernova:

stars Life track stages

formation of protostar, convective contraction, radiative contraction, self sustaining fusion:

interstellar medium

gas and dust found in the spaces between stars

hydrogen, helium, and a few heavier elements

gases in the interstellar medium

gravity forms stars easier

gravity can form stars more easily if something aides it like two molecular clouds colliding:

how stars form

gravity causes a molecular cloud to contract, and the contraction continues until central object becomes hot enough to sustain nuclear fusion in its core:

whens the battle with thermal pressure

gravity is stronger in molecular clouds due to more density (more mass in volume) and due to low temps in molecular clouds gravity does this:

super nova

happens after gravity has crushed away degeneracy pressure and the iron core can no longer resist it, outer layers of star are shot into space:

thermal pulses

helium fusion rates spike during helium shell fusion are:

carbon

helium fusion will result in a _____ core:

photons

how molecular clouds quickly rid themselves of thermal energy build up:

molecular clouds

interstellar clouds where stars are born due to conditions cold and dense enough for atoms to form molecules:

1% of molecular clouds mass

interstellar dust accounts for this percent of the mass of a molecular cloud:

70% hydrogen, 28% helium, 2% heavier elements

interstellar medium contents

neutron star

is the ball of neutrons left behind the when an iron core collapses into a massive super novae, about 10 km in radius with more mass than our sun:

novae

less luminous then super but still pretty darn bright happens on white dwarfs when fusion starts again from accretion of the white dwarf in binary system:

between 2 and 3 solar masses

limit of size for a neutron star:

planetary nebula

low mass stars like the sun will eventually eject their outer layers, the exposed core will still be very hot, radiation will ionize gasses making it grow brightly as a:

1987A

most recently known supernova was in the large Magellanic cloud in this year and so named:

gravity is super strong on a

neutron star

x-ray burst

neutron stars version of white dwarfs novae, but release x-rays:

white dwarf supernovae

occurs when a white dwarf has reached the white dwarf limit(carbon bomb):

gas infall

one way that a protostar gains mass(continues till gas is gone):

protostellar wind

outward flow of particles similar to the solar wind:

gravitational equilibrium

outward push of gas pressure balances the inward pull of gravity:

white dwarfs, then become to cold to emit light

planetary nebula become

event horizon

point of no return for objects entering black hole:

singularity

point where all black hole matter is crushed to single point:

neutron degeneracy pressure

prevents gravity from crushing neutron star:

carbon monoxide

produces radio emission lines allowing the mapping of molecular clouds:

1.0E6 K or one million Kelvin

protostar central temp:

3000 K

protostar surface heats up to this and then remains there until contraction halts:

LIfe of a high mass star

protostar, blue main sequence, red supergiant, hellium core super giant, multiple shell fusion supergiant, supernova, neutron star or black hole.

life of a low mass star

protostar, yellow main sequence, red giant, helium core fusion star, double shell red giant, planetary nebula, white dwarf:

binary system

prototstars can be very close to each other, gravity can cause them to orbit each other due to their angular momentum helping form:

protostellar disk

rapid rotation prevents gas from falling on a protostar and forms this:

pulsars(first known as little Green Men)

rapidly pulsing radio waves in space coming from neutron stars:

helium-capture reaction

reactions in which helium nucleus fuse with other nucleus:

gravitational red shift

red shift in black holes caused by gravity:

oldest stars possible

should consist of only hydrogen, and helium:

interstellar reddening

stars around the edges of molecular clouds are redder because dust blocks blue light better than red, this is referred to as:

intermediate-mass stars

stars born with masses between 2 and 8 solar masses:

high-mass stars

stars born with masses greater than 8 solar masses:

clusters

stars form in large:

low mass stars

stars that are born with less than 2 solar masses (2Msun) of material:

more recent stars

stars with more heavy elements are probably:

crab nebula

still visible supernova remnant:

hypernova

super nova that causes a black hole:

thermal pressure

temperature dependent pressure in ordinary gas clouds:

100 million K

temperature where helium core can start helium fusion:

protostar

the dense center of a molecular cloud fragment(look like stars but not quite hot enough for nuclear fusion):

molecular cloud cores

the dense clumps in a molecular cloud that form stars:

Schwarzschild radius

the radius of the event horizon:

radiation pressure

the reason stars have a maximum mass:

close binary system

these stars no longer have angular momentum, orbital separation is < .1 AU with orbital periods of just a few days:

brown dwarfs

this is a "failed star" due to degeneracy pressure will slowly radiates away its thermal energy cooling with time:

degeneracy pressure

this kind of pressure caused by density prevents objects with masses less than .08Msun from becoming true stars:

10 K-30 K

typical temperature of a molecular cloud:

takes forever to cross event horizon(but actually is squeezed and stretched to oblivion:

view from spaceship if friend jumped into black hole:

iron cant generate any nuclear energy

what element doesn't generate nuclear energy:

neutron star

what is left behind after a super nova:

Algol paradox

when binary stars are born at the same time, the more massive star must have shorter life, mass exchange happens:

helium white dwarfs

when degeneracy pressure prevents the collapse of the helium core before fusion the core will become a:

main sequence star

when protostar internal temp reaches 10E6 K and contraction stops a star of this type is born:

spacetime

when space and time are bundled up together to form a fourth dimension near event horizon:

super dense

white dwarfs are_________, like the amount of mass in the sun in the size of the earth.

more massive(higher gravity compresses them).

white dwarfs that are smaller in size are actually:

protostellar jets

young prototstars fire these high speed streams of gas(usually two in opposite directions):