LQ 12

In studying the surfaces of solid bodies in the solar system, astronomers have learned that the number of craters (per unit area):

is roughly proportional to the age of the surface we are examining

Which of the following is a way that the planet Mercury is similar to the Moon?

its surface is heavily cratered

Mercury is a small planet and therefore has trouble holding on to an atmosphere. How then do scientist account for the extremely thin atmosphere that was found around the planet in 1985?

the Sun's "wind" of particles is chipping atoms off the surface of Mercury

For scientists, one bar is

the average height of the ozone layer above the Earth (before we began to deplete it)

Which of the following is NOT evidence that objects from space collide with the Earth?

the crater at the top of the Mount St. Helens volcano

Which of these did the June 1908 impact event in Siberia and the 2013 event in the Russian city of Chelyabinsk have in common?

they both exploded high in the atmosphere and produced a shock wave that reached the ground

What is one important way in which both the Moon and Mercury are different from Earth?

they do not have an atmosphere

In which region of the Earth's atmosphere have you spent most of your life?

troposphere

Today, a significant amount of new gas is joining the atmosphere of the Earth from what source:

volcanoes release gas that was trapped within the Earth

What is the most important reason that astronomers have learned more about our planetary system in the last 30-40 years than all of history before then.

we have been able to send spacecraft to gather information about planets and moons up close

On which of the planets (other than Earth) could a human being step out of a spacecraft and survive without any protective gear (special suit, oxygen tanks, etc)?

you can't fool me; there is no other planet on which we could survive unprotected

Which planet in the solar system has not been examined by spacecraft instruments that have either flown by or orbited them?

Earth

A planet in our solar system whose composition resembles that of our Sun is

Jupiter

What relatively recent event shows that impacts continue to happen in our solar system even today?

a comet (which broke into more than 20 pieces) hit the planet Jupiter in 1994

When a projectile (a rock from space, say) hits the surface of the Moon, which of the following do we NOT get?

a gushing out of lots of water that had been frozen inside the ground on the cold Moon, but is briefly heated by the impact

These days the theory of the Earth's Moon's origin that best fits with the facts we have about the Moon is:

a large object hit the Earth and the collision produced a filament of material that condensed to make the Moon

One way in which the ozone layer is useful for life forms on the Earth's surface is that it

absorbs ultra-violet light, preventing much of it from reaching the surface

When chemists say that a planet's upper regions are reduced,they mean that these regions

are dominated by the element hydrogen and its compounds

Why are the largest craters we find on the Moon and Mercury so much larger than the largest craters we find on the Earth?

because the largest craters were made early in each world's history, and geologic activity has erased all traces of this early period on the Earth's surface

The first trans-Neptunian object astronomers found (in 1930) is called

ceres

Which of the following is NOT something that was accomplished by the Apollo missions to the Moon?

discovering that the Moon has a great deal of water under its surface

Sometimes, when the Moon is a thin crescent, you can still dimly make out the full disk of our satellite. What is the reason for this?

light reflecting from the Earth onto the Moon

All the planets (without exception)

revolve around the Sun in the same direction

Scientists have been concerned about a set of industrial chemicals called CFC's (chlorofluorocarbons) because they:

rise into the atmosphere and destroy ozone

In 1980, scientists suggested that the great mass extinction of 65 million years ago (which ended the reign of dinosaurs) may have been caused by a large impact from space. What discovery gives a big boost to this idea?

the discovery of a buried crater (about 200 km across) near Chicxulub, Mexico

In the far future, a visiting tourist from another planetary system asks to see the most massive object in our solar system. Where would you take him/her/it?

the sun

What makes astronomers think that impact rates for the Moon must have been higher earlier than 3.8 billion years ago?

there are ten times more craters on the older highlands than the younger maria