Astronomy Exam 3 Study Guide

our Sun, the death of stars, black holes

how far does the corona extend into space

over 1 AU

####what are the low-high temperatures of the transition region of the sun

10,000 K - 1 million K

####how long do most granules in the photosphere last

5-10 minutes

####how thick is the photosphere

400 km

####how hot is the Sun's atmosphere

over 1 million K

####what form does most of the energy from a solar flare take

UV and X-ray light

####why are sunspots cooler than the rest of the surface

their magnetic fields temporarily prevent convection, cooling them off

####why are sunspots seen in pairs

magnetic fields have north and south poles

####what causes the solar cycle

magnetic activity

####who discovered the solar cycle of sunspots

Schwabe

####what is the lighter region on the edge of a sunspot

penumbra

####where does solar wind primarily come from

coronal holes

####what element was discovered in the chromosphere before it was found on Earth

helium

####what region is right above the photosphere

chromosphere

####what is a photon

a positive lepton

####what region is right outside of the Sun's core

radiative zone

####Who first correctly identified the composition of the Sun

Payne-Gaposchkin

####how do we know the composition of the Sun

absorption spectra

####what may be the cause of short-duration gamma-ray bursts

the collision of two stellar corpses

####how did astronomers locate gamma-ray bursts

comparing with telescopes in other wavelengths

####gamma-ray burst

a sudden burst of gamma rays from deep space; such bursts apparently come from distant galaxies, but their precise mechanism is unknown

####what happens when a white dwarf star goes over the Chandrasekhar limit

it becomes a type 1 supernova

####Chandrasekhar limit

the maximum mass of a white dwarf before it collapses

####pulsar

a rapidly spinning neutron star that produces radio waves

####who discovered the first pulsar in 1967

Jocelyn Bell Burnell

####how long do supernovae usually last

a few months to a few years

####what is the possible upper limit in the mass of a neutron star

3 solar masses

####what is the heaviest element produced by burning in a massive star

iron

####what is the upper limit on a star's initial mass if it is likely to become a white dwarf

8 solar masses

####what form does the carbon in a white dwarf's core take

a diamond-like crystal lattice

####what does the electron pressure in a white dwarf result from

Pauli's Exclusion Principle

####what is the sensitivity of the LIGO

1/10,000 of a proton diameter

####what is the LIGO

a special observatory designed to detect gravitational waves

####how hot can material entering a black hole get

100 million K

####what is the first thing LIGO detected

the merging of two black holes

####what was the first black hole binary system discovered

Cygnus X-1

####what is a black hole binary system

a system consisting of 2 black holes in close orbit around each other

####what causes spaghettification

tidal forces

####what is gravitational redshift

the lengthening of the wavelength of a photon due to its escape from a massive gravitational field

####how did scientists test if gravitational redshift occured

with a hydrogen maser on a rocket

####gravitational lensing

the curving of light by a large mass between the observer and an object

####what weight class is the sun

middleweight

####most prevalent elements in stars

hydrogen & helium

####what form of matter does the sun take

plasma; an ionized gas

####what are the 3 inner layers of the sun

core, radiative zone, connective zone

####what are the 3 outer layers of the sun

photosphere, chromosphere, corona

####core of sun

hotter and denser than surface, nuclear fusion takes place

####radiative zone of sun

still so hot that all of the atoms are ionized, energy is transported by radiation (photons) in this zone

####convection zone of sun

energy transported upward by rising hot gas

####photosphere of sun

visible surface of sun

####chromosphere (transition region) of sun

is hotter than the photosphere

####corona

outermost layer of sun's atmosphere

####what is solar wind

stream of hot charged particles coming out of the sun

####what happens when solar wind interacts with Earth's magnetic field

auroras

####how long is the sun's solar cycle

22 years

####solar cycle

a 22-year cycle during which the Sun's magnetic field reverses its polarity twice

####what is the dark part of a sunspot called

umbra

####what is the red part of a sunspot called

penumbra

####coronal loop

part of the lower corona where solar radiation is traveling along solar magnetic lines

####coronal mass ejection

a part of coronal gas that is thrown into space from the sun

####what is another name for light weight stars

red dwarf stars

####first step in death of middle weight star

hydrogen fuses into helium in the core

- 11 mill

####second step in death of middle weight star

helium core starts collapsing

####third step in death of middle weight star

helium fuses into carbon

####last step in death of middle weight star

all gas around core is dispersed, core turns into a diamond called a white dwarf

####(heavy & super heavy) what does carbon fuse into

neon

- 40 mill

####(heavy & super heavy) what does neon fuse into

oxygen

####(heavy & super heavy) what does oxygen fuse into

silicone

####(heavy & super heavy) what does silicone fuse into

iron

####(heavy & super heavy) what does the iron core turn into

neutron core

####(heavy & super heavy) what happens after neutron core

supernova explosion

####what does a heavy weight become after supernova

Neutron star

####what does a super heavy weight become after supernova

black hole

####what is the quantum reality

very small, subatomic

####what is the newtonian reality

how we perceive the world; energy, mass, time, volume

####what is the relativistic reality

special theory, general theory

####special theory

objects going at or near the speed of light

####general theory

explains gravity

####what happens when an object hits the speed of light

its weight becomes infinitely large

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