ASTRO 7N EXAM 2 FULL REVIEW SET 2026
QUESTIONS ANSWERS VERIFIED
◉ If a red giant and a red main-sequence star look equally bright
which one is farther away? Answer: The red giant
◉ When are the heaviest nuclei in the universe formed? Answer:
During a supernova explosion
◉ In the Sun Hydrogen-2 + proton → ? Answer: Helium-3
◉ Which object has the smallest radius? Answer: Neutron star
◉ Why does the main sequence part of a star's life end? Answer: The
Hydrogen in the core is exhausted
◉ Which star has the shortest main-sequence lifetime? Answer: A
main sequence star with surface temperature 20000 K
◉ Why are many of the brightest 100 stars NOT on the main
sequence? Answer: The most luminous stars are giants or
supergiants that have finished their main-sequence lifetimes
, ◉ A 2-solar-mass and a 0.2-solar-mass main sequence star are the
same distance away Which appears brighter? Answer: The 2-solar-
mass star appears brighter
◉ What is the temperature of the Sun's photosphere? Answer: About
6000 K
◉ What would make the estimated number of communicating
civilizations in our Galaxy larger? Answer: A larger average number
of planets that could support life per star
◉ If the Sun had twice its mass which planet would fall in its
habitable zone? Answer: Jupiter
◉ In the Kepler transit activity what were the exoplanet's orbital
period and percent brightness drop? Answer: 5 days and 0.30%
◉ How do astronomers measure a star's temperature? Answer: By
looking at which absorption lines appear in its spectrum
◉ In the inverse square law activity what wattage must the top bulb
have to look as bright as a 25-W bulb below it? Answer: 100 Watts
QUESTIONS ANSWERS VERIFIED
◉ If a red giant and a red main-sequence star look equally bright
which one is farther away? Answer: The red giant
◉ When are the heaviest nuclei in the universe formed? Answer:
During a supernova explosion
◉ In the Sun Hydrogen-2 + proton → ? Answer: Helium-3
◉ Which object has the smallest radius? Answer: Neutron star
◉ Why does the main sequence part of a star's life end? Answer: The
Hydrogen in the core is exhausted
◉ Which star has the shortest main-sequence lifetime? Answer: A
main sequence star with surface temperature 20000 K
◉ Why are many of the brightest 100 stars NOT on the main
sequence? Answer: The most luminous stars are giants or
supergiants that have finished their main-sequence lifetimes
, ◉ A 2-solar-mass and a 0.2-solar-mass main sequence star are the
same distance away Which appears brighter? Answer: The 2-solar-
mass star appears brighter
◉ What is the temperature of the Sun's photosphere? Answer: About
6000 K
◉ What would make the estimated number of communicating
civilizations in our Galaxy larger? Answer: A larger average number
of planets that could support life per star
◉ If the Sun had twice its mass which planet would fall in its
habitable zone? Answer: Jupiter
◉ In the Kepler transit activity what were the exoplanet's orbital
period and percent brightness drop? Answer: 5 days and 0.30%
◉ How do astronomers measure a star's temperature? Answer: By
looking at which absorption lines appear in its spectrum
◉ In the inverse square law activity what wattage must the top bulb
have to look as bright as a 25-W bulb below it? Answer: 100 Watts
