1/ Astronomers estimate that the plains of Venus are only about 500 to 600 million years old. How do they
estimate dates like this?
by counting the craters visible on the surface and comparing crater counts to other worlds
by looking for little brass plates that give the founding date and the name of the governor at the time
by looking at the radioactive rock samples that have been returned to Earth from Venus
by seeing how much the continental plates on which the Venus plains are floating have spread apart
by noting that all the plains on all the terrestrial planets have the same age
2/ Why does Mars have an overall reddish color when we see its surface from afar?
the giant volcanoes on Mars are constantly spewing out reddish lava
Mars is completely cloudy, and its clouds are made of red materials
This is an optical illusion caused by the Earth's atmosphere scattering the colors of light differently
The martians are constantly at war, and spilling a lot of red blood
The material of Mars' surface contains a lot of iron oxide, the same chemistry that makes rusting metals look reddish
3/ The process by which Venus became so much hotter than the Earth is called:
the runaway greenhouse effect
the twisted sister effect
4/ Which of the following is evidence for volcanic activity on Venus?
the existence of large volcanic mountains such as Sif Mons
the discovery of thousands of small volcanic cones of the surface of Venus
all of these
the pancake domes of Venus
the fact that the lava plains are only 500 million or so years old
5/ The observation that began the 19th and early 20th century fascination with Mars as a place for life was:
the landing of Martian spacecraft in New Jersey in 1938
Schiaparelli's seeing what seemed to him to be long straight features on the red planet
Percival Lowell's discovery of an entire network of artificial canals built by martians
the discovery of the Martian moons
the images sent back by the Viking spacecraft mission
6/ Which of the following is NOT one of the key reasons that so many spacecraft from Earth have visited Venus and Mars?
they resemble the Earth in a number of significant ways
both have tantalized us when seen through a telescope -- one because it is perpetually covered by clouds, the other because it shows seasonal changes
their atmospheres are very similar to the Earth in terms of their chemical make-up
they are the two planets closest to the Earth
they each have a solid surface on which we can trace their geological history
7/ The largest volcano on Mars is called:
Olympus Mons (Mt. Olympus)
the Red Spot
8/ Mars appears to have long branching channels that have the appearance of being formed by a flowing liquid. Yet we know that liquids would not stay liquid in the very thin atmosphere we have on the Martian surface? So how can we explain the channels?
the channels are artificial, made by a race of Martians that died out
they were made by wind-blown dust during the great Martian dust storms
they are made by plate tectonics; by plates in the crust separating
they were formed by volcanic lava from Olympus Mons
Mars had a thicker atmosphere long ago when the channels formed
9/ Astronomers believe that Mars formed with a much thicker atmosphere than it has today. Where did this atmosphere go?
it was absorbed by the rocks on Mars, which are much more absorbent than on Earth
it was drawn into the crust and mantle of Mars through the enormous cracks of the Mariner Valley canyon system
it escaped into space (and some later froze out as Mars got cold)
no one has any good theories about this; it is an unsolved mystery
it is trapped in bubbles inside the rocks on the martian surface
10/ The canals that late 19th and early 20th observers thought they saw on Mars turned out to be:
enormous cracks caused by extensive plate tectonics on Mars
huge chains of thousands of large volcanoes
built by the same race of ancient martian engineers who constructed the "face on Mars"
very narrow oceans of water