AST 111 Final Exam Practice

1.

1 point

A bit of matter that enters Earth's atmosphere and survives to reach the ground is called

A meteor

A dwarf planet

A meteorite

A minor planet

An asteroid

2.

1 point

A meteor shower is produced when

A large number of sporadic meteors are observed

The Earth passes through the asteroid belt

Massive particles are carried outward from the sun by solar wind and enter Earth's atmosphere

The Earth passes through the orbital path of a comet

Meteors cause condensation in upper atmosphere that leads to early morning rains

3.

1 point

A chondrite is a meteor that has

Never been heated

Been heated but never very hot

Been heated to a high temperature

Been melted

Entered Earth's atmosphere but will be destroyed before reaching the ground

4.

1 point

Currently the most accepted explanation of the Tunguska Event is the explosion of

A German U-2 rocket

An iron meteor just above the surface of the earth

A stony asteroid just above the surface of the earth

A mini black hole in the earth's atmosphere

An alien spacecraft as it crashed to earth

5.

1 point

The Allende meteorite is important because

It is the largest iron meteorite ever found

Its composition suggests that it is very old and unchanged from when it formed

It is the object that produced the Tunguska event

It contains the most well defined Widmanstatten patterns ever found

It is the only meteorite to ever strike and kill a person

6.

1 point

The iron meteorites

Represent the largest number of falls

Are only found in the Antarctic

Are composed of carbonaceous chondrites

Are responsible for most of the meteor craters on the surface of the moon

Appear to have formed from the interiors of molten objects of planetesimal size

7.

1 point

Most of the asteroids orbit the sun in a belt between the orbits of

Venus and Earth

Earth and Mars

Jupiter and Saturn

Mercury and Venus

Mars and Jupiter

8.

1 point

An asteroid could produce an iron core and a silicate mantle if it

Differentiated

Outgassed

Condensed

Accreted

Sublimed

9.

1 point

What evidence exists that some of the asteroids were geologically active?

A few of the larger asteroids show small volcanic mountains

The moons of Mars, thought to be captured by asteroids, show evidence of flooding by lava

The meteorites that are breccias could only have formed in a molten mantle

Spectroscopically, Vesta appears to have regions of small lava flows

Io is very geologically active with sulfur volcanoes

10.

1 point

Uranium, thorium, and the radioactive isotope of potassium cannot supply the heat to melt small planetesimals, yet are sufficient to melt the interior of Earth. This is because these elements

Decay slowly, and a thick crust must trap heat generated if it is to melt the interior

Were not present in the solar nebula at the location where the asteroids formed

Are only found in the outer layers of asteroids and not in the core

Are very volatile and evaporated from the asteroids before they could decay

Are only found on rocks that formed on the earth and in no other celestial objects

11.

1 point

The gas tail of a comet always

Trails behind the head along the orbital path

Extends ahead of the head along the orbital path

Points toward the sun

Points away from the sun

Points perpendicular to the orbital path

12.

1 point

The short-period comets do not have randomly oriented orbits because

They are affected by the sun's gravity

They are affected by the solar wind

Their orbits have been altered by encounters with the planets

Their orbits are altered by the drag of their tails in the solar wind

They all were originally objects ejected from the asteroid belts

13.

1 point

One theory suggests that the bodies in the Oort cloud formed

Near the present orbits of the terrestrial planets

Near the present orbits of the Jovian planets

At high temperatures

From silicate materials

In outside of the original solar nebula

14.

1 point

The density of Comet Halley was found to be about 0.2 g/cm3. This implies that Comet Halley

Is composed of about 50% rock and 50% frozen water and methane

Is loosely packed ices with a small amount of rocky material

Formed in the inner solar system and was ejected by Jupiter to the Kuiper belt

Is really an S-type asteroids

Was once a moon of Neptune and was ripped away by a large impact

15.

1 point

The _____ is a disk-shaped cloud of icy bodies believed to extend from about 40 AU out to 100 AU. It is believed that short-period comets originate from this region.

Oort cloud

Widmanstatten cloud

Apollo-Amor

Kirkwood region

Kuiper belt

16.

1 point

Sungrazers are

Asteroids located inside the orbit of Mercury

Meteorites that have a composition very similar to that of the sun

Asteroids removed from Kirkwood's gap by the influences of the sun and Jupiter

Comets, which get very close to the sun

Cattle that only feed when the sky is clear

17.

1 point

One important way a major impact on Earth is thought to have triggered extinction of many species is

The fragments hit animals on their heads, killing them

The Earth's moon was thrown out of its orbit

Because of changes to the worldwide climate

Wrong - major impacts are not thought to have triggered extinctions

18.

1 point

The Tunguska impact in 1908 in Russia left behind

A giant crater

Extinction of many life forms

No crater

19.

1 point

The Cretaceous extinction 65 million years ago is thought to have been caused by

The impact of a small asteroid

The impact of one of the Jovian planets

The impact of one of the terrestrial planets

20.

1 point

During the Cretaceous extinction 65 million years ago _____ percent of the species on Earth died out

1

7.5

75

750

21.

1 point

The impact of a large comet with Earth has been suggested to have caused the extinction of the dinosaurs. The impact site of this comet is in or near

Iowa

Hudson Bay

Crater Lake, Oregon

Canberra Australia

Chicxulub Mexico

22.

1 point

What type of physical process has led to the different types of meteorites that we see today?

Nuclear Fusion

Accretion

Condensation

Differentiation

23.

1 point

How is the coma of a comet produced?

Rocky material breaks off from the comet to form the coma

The coma is a cloud of particles that the comet has swept up in its orbital path

Ices vaporize to become gas that form around the comet nucleus

Particles in the solar wind get caught in the comet's magnetic field to form the coma

24.

1 point

What characteristic of long period comets suggest they come from the Oort cloud?

They have longer Type II tails than short period comets

Their orbits have random inclinations with respect to the ecliptic plane

Their orbits are nearly circular

They tend to appear larger in diameter than short period comets

25.

1 point

Which of the following is evidence for the connection between comets and meteor showers?

Meteor and comets have the same appearance in the sky

Meteor showers always occur when a comet is visible

Meteor showers always occur 6 months after a comet passes Earth

Meteor showers are a predictable, annual event

26.

1 point

The largest object orbiting between Mars and Jupiter is _____ which is _____.

Ceres; an asteroid

Ceres; a dwarf planet

Pluto; an asteroid

Pluto; a dwarf planet

27.

1 point

Two major kinds of meteorites are

Iron and stony

Hydrogen and helium

Jovian and terrestrial

Lunar and solar

28.

1 point

Asteroids are discovered by their

Great gravitational effect on Mars' orbit

Great gravitational effect on Jupiter's orbit

Orbital motion around the planet Venus in photographs

Orbital motion among the stars in successive images

29.

1 point

Which one of the solar system objects below has the smallest mass?

A comet

Jupiter

Mars

Our moon

Venus

30.

1 point

The solid nucleus or head of a comet is about the size of

Jupiter

The moon

Earth

Much larger than any of the above

Much smaller than any of the above

31.

1 point

The type I tail of a comet shows a spectrum of bright lines on a dark background of space (an emission line spectrum). From this, one can conclude that the tail contains

Dust

Thin gas

No atoms at all, just empty space

The spectrum does not tell which of the above is true

32.

1 point

The type II tail of a comet shows a spectrum of absorption lines on a bright background (like the Sun's spectrum). From this, one can conclude that the tail contains

Dust

Thin gas

No atoms at all, just empty space

The spectrum does not tell which of the above is true

33.

1 point

A cell's DNA molecules are constructed of

Amino acids

Proteins

Sugars, phosphates, and bases

All of the above

None of the above

34.

1 point

DNA molecules contain patterns for the production of

Proteins

Enzymes

Both A and B

Neither A nor B

35.

1 point

The processes of life

Extract energy from the surroundings

Maintain the organism

Modify the surroundings to promote survival

All of the above

36.

1 point

Life

Reproduces itself

Contains information necessary for reproduction

Both A and B

Neither A nor B

37.

1 point

The first complex life appeared on Earth about 0.5 billion years ago during the

Jurassic Period

Mississippian Period

Cambrian Period

Precambrian Period

Neolithic Period

38.

1 point

The Miller experiment created

Life

Artificial proteins

DNA

Simple molds

Amino acids

39.

1 point

The "framework" of molecules important for life on Earth is based on _____ atoms

Carbon

Helium

Silicon

Oxygen

Nitrogen

40.

1 point

From which these planets do we have known samples of material?

Mercury

Venus

Mars

All of the above

None of the above

41.

1 point

The stars most likely to have inhabited planets are

Spectral type "G" to "K" main sequence stars

Main sequence spectral type "O" stars

Proto-stars

Neutron stars

Black holes

42.

1 point

The habitable zone is

The region on a planet where conditions are not acceptable for life to exist

A region around a star where a planet has temperatures that permit the existence of liquid water

The visible surface of a star

Only found around black holes

A region on a young planet where amino acids can begin to form DNA molecules

43.

1 point

Why are massive main sequence stars not likely to have planets that contain life?

The life zones around these stars are too small

These stars would sweep away all of the material from which planets could form

These stars are too hot to allow water to exist as a liquid on any planet that might form

These stars are on the main sequence for too short a time to allow life to evolve

44.

1 point

Which of the answers below is NOT a factor in the Drake equation estimating the number of communicative technological civilizations in our galaxy?

The number of stars in our galaxy

The fraction of stars with planets

The number of suitable planets (with liquid water) per system of planets

The fraction of suitable planets on which life arises

The distance of the Earth from our sun

45.

1 point

Current searches for extraterrestrial intelligence use radio telescopes to

Listen to many stars at the same time at one frequency

Listen to many frequencies at the same time

Transmit one frequency to many stars at the same time to get replies in a few minutes

Transmit many frequencies to one star at the same time to get replies in a few minutes

Look for life on Earth

46.

1 point

The most likely low interference region of the radio spectrum for communication with other civilizations is the water hold, the part of the spectrum

At the radio emission of hydrogen in our galaxy

At the radio emission of OH

At the radio emission of noise from Earth's atmosphere

Between the radio emissions of hydrogen and OH

Near the radio band where water in the Earth's atmosphere strongly absorbs energy

47.

1 point

What is important about the habitable zone around a star that makes astronomers believe life could exist there?

The level of electromagnetic radiation from the star is zero there

Only on the surface of the star's photosphere can complex organic molecules be found

Only planets in the habitable zone will have atmospheres

In the habitable zone water can exist as a liquid on the planet

48.

1 point

When estimating the number of technologically advanced civilizations in our galaxy, it is useful to consider

The average life span of an alien

The average life span of the civilization

The distance to the civilization's planet

The type of advanced communication they use

49.

1 point

_____ is a segment of a chromosome that controls a specific function

DNA

RNA

An enzyme

A gene

An amino acid

50.

1 point

DNA is coiled into a tight spiral and makes up the _____ that are the genetic material in a cell

Genes

Amino acids

Enzymes

Nucleus

Chromosomes