chapter 14 Flashcards
3.85 x 10^26 watts
sun’s luminosity
- a balance between the outward force due to the pressure of radiation produced inside and the inward force of gravity
- radiation pressure & force of gravity must be just enough to hold up the weight of the sun without collapsing
hydrostatic equilibrium (2)
the short-range force between protons & neutrons that holds atomic nuclei together
strong nuclear force
- the combination of 2 less massive atomic nuclei into a single, more massive atomic nucleus
- 4 hydrogen nuclei become 1 helium nucleus plus energy
nuclear fusion (2)
E = mc^2
exchange rate of mass & energy
the release of energy from the fusion of 4 hydrogen nuclei into a single helium
hydrogen fusion
- the innermost region of a planetary/star interior
- density of matter in the core is 150 times the density of water
- temperature is ~15 million K
- half the energy produced by the sun comes from the inner core
core (4)
- hydrogen-1 →hydrogen-2 + pos e + v, then pos e + neg e → y + y (gamma rays)
- hydrogen-2 + hydrogen-1 → helium-3 + y
- helium-3 + helium-3 → helium-4 + hydrogen-1 + hydrogen- 1
proton-proton chain (3)
- colliding protons create deuterium
- protons collide with deuterium nuclei to produce helium-3
- helium-3 nuclei collide to create helium-4
3 steps of the proton-proton chain (3)
positively charged subatomic particle
positron
- very low-mass, electrically neutral particle emitted during beta decay
- can penetrate great quantities of matter
neutrino (2)
an isotope of hydrogen; 1 proton and 2 neutrons
deuterium
- matter made up of antiparticles
- form gamma rays photons
antimatter (2)
thermal energy of particles are transferred to adjacent particles by collision
conduction
- hot energy rises, cools as it nears the surface, and falls to be heated and rise again
- a region of turbulent plasma between a star’s core and its visible photosphere
convection (2)
waves/particles of energy traveling through space or a medium
radiation
a measure of how effectively a material blocks the radiation going through it
opacity
- a region within a star where energy is transported outward by radiation
- peak temp of 15 million K at the sun’s core, then 2-3 million K at the other margin
radiative zone (2)
a region within a star where energy id transported outward by convectionn
convection zone
historical observation that only about a 1/3 of predicted neutrinos by theory seemed to be coming from the sun
solar neutrino problem
the use of solar oscillations to study the interior of the sun
helioseismology
- the apparent surface of the sun as seen in visible light
- base of the atmosphere
photosphere (2)
- ## the region of the sun’s atmosphere located between the photosphere and the corona
chromosphere
the hot, outermost part of the sun’s atmosphere
corona
the relationship between temp & density between the layers of sun’s atmosphere are inversely proportional (except the corona)
temperature-density relationship
the temperature at which a blackbody–like a star– appears to radiate
effective temperature
we see the sun at an angle, which is why we can’t see super deeply into the sun’s atmosphere
limb darkening
a cooler transitory region on the solar surface produced when loops of magnetic flux break through the sun
sunspots
an area of the sun’s chromosphere anchoring bursts of intense magnetic activity
active region
low-density region in the solar corona containing an open magnetic field lines where coronal material can stream into space
coronal holes
gas & dust that fill space between stars within a galaxy
interstellar medium
rotation of different parts of a star at different rates
differential medium
a 22 yr cycle where the sunspot activity increases and then decreases, reversing every 11 years
sunspot cycle
an arch-like projection above the solar photosphere often associated with a sunspot
prominence
an explosion on the sun’s surface associated with a complex sunspot group and a strong magnetic field
solar flares
gas composed of charged particles but may also include some neutral atoms
plasma
an eruption on the sun that ejects hot gas and energetic particles at much higher speeds than are typical in the solar wind
coronal mass ejection (CME)
the solar wind blows against the interstellar medium and clears out an area like the inside of a bubble
heliosphere
