2025 ASTR 1102 Final Exam with accurate
questions and verified answers covering
stellar evolution, galaxies, cosmology, and
advanced astronomy concepts.
Parsecs are used to measure:
j j j j
A) Distance
j
B) Time
j
C) Speed ......answer.....A
j jj
Star A is seen at a parallax angle of 0.2 arcsec while Star B at an angle of
j j j j j j j j j j j j j j j j j j
1.2 arcsec. Which star is further away and by how much/less?
j j j j j j j j j j
,A) Star A is 6 times further away
j j j j j j j
B) Star B is 6 times away
j j j j j j
C) Star A is 10 times further away
j j j j j j j
D) They are both at the same distance ......answer.....A
j j j j j j j jj
Mars is approximately twice as far from the Sun as Venus. How much
j j j j j j j j j j j j j
dimmer does the Sun appear from Mars?
j j j j j j
A) Half as bright
j j j
B) One third as bright
j j j j
C) One quarter as bright
j j j j
D) One sixteenth as bright ......answer.....C
j j j j jj
,Two stars have the same temperature and luminosity, but one is 10 lig
j j j j j j j j j j j j
ht years from the Earth, and the other is 1000 light years away. The m
j j j j j j j j j j j j j j
ore distant star appears to be
j j j j j
A) 10x fainter
j j
B) 100x fainter
j j
C) 10,000x fainter
j j
D) 100,000,000x fainter
j j
E) The same brightness ......answer.....C
j j j jj
α Fic has the same mass as the Sun, but is about 100x more luminous. If
j j j j j j j j j j j j j j j j
the Sun has a total lifetime around 10 billion years, how long would yo
j j j j j j j j j j j j j
u expect α Fic to live, to the nearest power of ten?
j j j j j j j j j j j
, Hint: For stars of the same mass, the life-
j j j j j j j j
time ranges as one over the star's luminosity (i.e. the more luminous s
j j j j j j j j j j j j
tars live shorter lives).
j j j
A) 100 billion years
j j j
B) 1 billion years
j j j
C) 10 billion years
j j j
D) 100 million years
j j j
E) 1000 billion years ......answer.....D
j j j jj
The apparent brightness of a star is 3 x 10^-10 W m-
j j j j j j j j j j j
2 and it's parallax 0.05 arcsec. Estimate the star's lifetime as compare
j j j j j j j j j j j
d to that of the sun. Round up your final answer.
j j j j j j j j j j
questions and verified answers covering
stellar evolution, galaxies, cosmology, and
advanced astronomy concepts.
Parsecs are used to measure:
j j j j
A) Distance
j
B) Time
j
C) Speed ......answer.....A
j jj
Star A is seen at a parallax angle of 0.2 arcsec while Star B at an angle of
j j j j j j j j j j j j j j j j j j
1.2 arcsec. Which star is further away and by how much/less?
j j j j j j j j j j
,A) Star A is 6 times further away
j j j j j j j
B) Star B is 6 times away
j j j j j j
C) Star A is 10 times further away
j j j j j j j
D) They are both at the same distance ......answer.....A
j j j j j j j jj
Mars is approximately twice as far from the Sun as Venus. How much
j j j j j j j j j j j j j
dimmer does the Sun appear from Mars?
j j j j j j
A) Half as bright
j j j
B) One third as bright
j j j j
C) One quarter as bright
j j j j
D) One sixteenth as bright ......answer.....C
j j j j jj
,Two stars have the same temperature and luminosity, but one is 10 lig
j j j j j j j j j j j j
ht years from the Earth, and the other is 1000 light years away. The m
j j j j j j j j j j j j j j
ore distant star appears to be
j j j j j
A) 10x fainter
j j
B) 100x fainter
j j
C) 10,000x fainter
j j
D) 100,000,000x fainter
j j
E) The same brightness ......answer.....C
j j j jj
α Fic has the same mass as the Sun, but is about 100x more luminous. If
j j j j j j j j j j j j j j j j
the Sun has a total lifetime around 10 billion years, how long would yo
j j j j j j j j j j j j j
u expect α Fic to live, to the nearest power of ten?
j j j j j j j j j j j
, Hint: For stars of the same mass, the life-
j j j j j j j j
time ranges as one over the star's luminosity (i.e. the more luminous s
j j j j j j j j j j j j
tars live shorter lives).
j j j
A) 100 billion years
j j j
B) 1 billion years
j j j
C) 10 billion years
j j j
D) 100 million years
j j j
E) 1000 billion years ......answer.....D
j j j jj
The apparent brightness of a star is 3 x 10^-10 W m-
j j j j j j j j j j j
2 and it's parallax 0.05 arcsec. Estimate the star's lifetime as compare
j j j j j j j j j j j
d to that of the sun. Round up your final answer.
j j j j j j j j j j
