Homework Question Set 8 -- Due Dec 4


1) How much more solar energy does Venus receive than the Earth, due to the fact that Venus s 0.72 times as far from the Sun?
0.72 times as much
1/0.72 =1.4 times as much
0.72^2 =0.52 times as much
(1/0.72)^2 = 1.92 times as much
0.28 times as much



2) Jupiter's chemical composition is closest to that of
the Sun
Earth
Mars
the Moon
Venus



3) Why do Mercury and the Moon have no atmosphere?
the temperature at their surfaces is high, so most gas molecules travel fast enough to escape the planet
the gravity at their surfaces is low, so most gas molecules travel fast enough to escape the planet
the only gas molecules they had originally were low in mass, so that they were immediately able to escape
they are both highly reflective



4) According to the classification adopted by the International Astronomical Union in the Summer of 2006, Pluto is
a planet.
the largest dwarf planet.
one of the dwarf planets, but not the largest.
a dog.



5) The tail of a comet is generally directed
away from the Sun because of solar wind and radiation pressure.
opposite the direction of motion as the commet passes through interplanetary matter.
toward the Sun because of the Sun's gravitational force.
along the comet's magnetic field lines.
none of the above.