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Astro 1-Exam 3 Questions And Answers
|Latest 2025 | Guaranteed Pass.
What is the sun comprised of? - Answer✔73% hydrogen 25% helium
why is the sun stable? - Answer✔outward force of gas pressure; inward force of gravity
Where does the gas pressure in the sun come from? - Answer✔nuclear fusion reactions in the
core at temperatures of 15 million degrees
What is the diameter of the sun compared to earth? mass? luminosity (compared to 100W
lightbulbs? - Answer✔diameter-109x; mass-333,000; luminosity- 4 x 10^24
What percent of mass in the solar system comes from the sun? - Answer✔99.9%
how long has the sun been shining? how much longer will it shine? - Answer✔4.5 billion years;
5.5 billion years
what are sunspots? - Answer✔slightly cooler regions on the sun's surface
what causes sunspots? how long are their cycles? - Answer✔magnetic activity preventing hot
material from rising to that region. they have 11 year cycles
what comprises helium-4? What does it release? What is it called? - Answer✔4 protons
combine to make helium-4 (2 protons, 2 neutrons); produces gamma rays; it is called the
proton-proton chain
What is the first step in Nuclear fusion? - Answer✔two protons stick together and one changes
into a neutron to produce deuterium (1 proton and 1 neutron)
What is the second step in Nuclear fusion? - Answer✔deuterium plus proton makes helium-3 (2
protons and 1 neutron bound together)
What is the third step in nuclear fusion? - Answer✔two helium-3 molecules combine to make
helium-4 and 2 protons
When is energy created in Nuclear fusion? - Answer✔in every step
1
, ©FYNDLAY 2024/2025 ALL RIGHTS RESERVED 11:08AM. A+
Where does the energy in Nuclear fusion come from? - Answer✔E= mc^2 because the mass of
helium is 4 less than the mass of 4 protons
What are the layers of the sun from inside to out? - Answer✔core, radiative zone, connective
zone, photosphere, chromosphere, flare, prominence, corona, solar wind
What is the core of the sun like? - Answer✔at center; high density and temperature; where
nuclear reactions occur and gamma rays produced
What is the radiative zone of the sun like? - Answer✔photons are repeatedly reabsorbed
and emitted, and the energy of an individual photon
can take on average 170,000 years to pass through
What is the connective zone of the sun like? - Answer✔hot gas rises and cold gas sinks;
light traverses in 1 week
What is the photosphere of the sun like? - Answer✔temperature 5780K; the surface that we
see; photons have been converted to visible wave- length, see granules due to convection
bringing ma- terial up and down in cells
What is the chromosphere of the sun like? - Answer✔red or orange color; temperature 4500K;
we see through this to the photosphere
What is the flare of the sun like? - Answer✔eruption coming out of Sun due to magnetic activity
What is the prominence of the sun like? - Answer✔hoop shaped eruption out of Sun due to
magnetic activity
What is the corona of the sun like? - Answer✔low density; temperature 1 million K; visible
during solar eclipse
What is the solar wind of the sun like? - Answer✔charged particles coming from Sun's sur- face;
permeate whole solar system
What is luminosity? - Answer✔the absolute power output at the source
What is brightness? - Answer✔apparent output as observed at some distance
What determines how bright a star appears based upon its luminosity? - Answer✔inverse
square law
What is the inverse square law? - Answer✔B= L/4πd^2; b-brightness, d-distance, L- luminosity
if two stars have the same luminosity and one is 10 times further away than the other, how
bright will it appear? - Answer✔it will appear 1/10^2 as bright which is 100 times fainter
2
Astro 1-Exam 3 Questions And Answers
|Latest 2025 | Guaranteed Pass.
What is the sun comprised of? - Answer✔73% hydrogen 25% helium
why is the sun stable? - Answer✔outward force of gas pressure; inward force of gravity
Where does the gas pressure in the sun come from? - Answer✔nuclear fusion reactions in the
core at temperatures of 15 million degrees
What is the diameter of the sun compared to earth? mass? luminosity (compared to 100W
lightbulbs? - Answer✔diameter-109x; mass-333,000; luminosity- 4 x 10^24
What percent of mass in the solar system comes from the sun? - Answer✔99.9%
how long has the sun been shining? how much longer will it shine? - Answer✔4.5 billion years;
5.5 billion years
what are sunspots? - Answer✔slightly cooler regions on the sun's surface
what causes sunspots? how long are their cycles? - Answer✔magnetic activity preventing hot
material from rising to that region. they have 11 year cycles
what comprises helium-4? What does it release? What is it called? - Answer✔4 protons
combine to make helium-4 (2 protons, 2 neutrons); produces gamma rays; it is called the
proton-proton chain
What is the first step in Nuclear fusion? - Answer✔two protons stick together and one changes
into a neutron to produce deuterium (1 proton and 1 neutron)
What is the second step in Nuclear fusion? - Answer✔deuterium plus proton makes helium-3 (2
protons and 1 neutron bound together)
What is the third step in nuclear fusion? - Answer✔two helium-3 molecules combine to make
helium-4 and 2 protons
When is energy created in Nuclear fusion? - Answer✔in every step
1
, ©FYNDLAY 2024/2025 ALL RIGHTS RESERVED 11:08AM. A+
Where does the energy in Nuclear fusion come from? - Answer✔E= mc^2 because the mass of
helium is 4 less than the mass of 4 protons
What are the layers of the sun from inside to out? - Answer✔core, radiative zone, connective
zone, photosphere, chromosphere, flare, prominence, corona, solar wind
What is the core of the sun like? - Answer✔at center; high density and temperature; where
nuclear reactions occur and gamma rays produced
What is the radiative zone of the sun like? - Answer✔photons are repeatedly reabsorbed
and emitted, and the energy of an individual photon
can take on average 170,000 years to pass through
What is the connective zone of the sun like? - Answer✔hot gas rises and cold gas sinks;
light traverses in 1 week
What is the photosphere of the sun like? - Answer✔temperature 5780K; the surface that we
see; photons have been converted to visible wave- length, see granules due to convection
bringing ma- terial up and down in cells
What is the chromosphere of the sun like? - Answer✔red or orange color; temperature 4500K;
we see through this to the photosphere
What is the flare of the sun like? - Answer✔eruption coming out of Sun due to magnetic activity
What is the prominence of the sun like? - Answer✔hoop shaped eruption out of Sun due to
magnetic activity
What is the corona of the sun like? - Answer✔low density; temperature 1 million K; visible
during solar eclipse
What is the solar wind of the sun like? - Answer✔charged particles coming from Sun's sur- face;
permeate whole solar system
What is luminosity? - Answer✔the absolute power output at the source
What is brightness? - Answer✔apparent output as observed at some distance
What determines how bright a star appears based upon its luminosity? - Answer✔inverse
square law
What is the inverse square law? - Answer✔B= L/4πd^2; b-brightness, d-distance, L- luminosity
if two stars have the same luminosity and one is 10 times further away than the other, how
bright will it appear? - Answer✔it will appear 1/10^2 as bright which is 100 times fainter
2
