Download Unit 5: Review Game Questions

Unit 5: Review Game Questions
1) How does the Sun's mass compare with that of the planets?
2) What does the term half life mean?
3) Explain why radioactive decay occurs in some atoms and not others.
4) Which planet, other than Earth, has visible water ice on it?
5) The odd tilt of this planet is an example of the major role large impacts have played in creating irregularities
in the solar system.
6) Where did the elements heavier than hydrogen and helium in the solar nebula come from?
7) The planet closest in size to Earth is __________________.
8) What are the main components of the Jovian planets?
9) Where are most of the known asteroids found?
10) How do asteroids differ from comets?
11) Which of the following best describes Pluto in terms of the general characteristics of terrestrial and Jovian
planets?
12) Some astronomers suggest that, rather than being a planet, Pluto is really just a large member of
__________________.
13) Explain why the solar nebula heated up as it collapsed.
14) Describe what happened during the accretion phase of the early solar system.
15) What percentage of the mass of the solar nebula consisted of the elements hydrogen and helium?
16) Why are the inner planets made of denser materials than the outer planets?
17) Describe the origin of almost all the large moons around the Jovian planets.
18) Observations of young stars (as well as theory) tell us that when the Sun was young the solar wind
was__________________.
19) What is a distinguishing characteristic of planetesimals which was critical to planetary formation?
20) Describe what happens when a nebula contracts.
21) According to the nebular theory, what are asteroids and comets?
22) Based on our current theory of the earth's formation, the water we drink came from __________________.
23) Briefly summarize the observed patterns of motion in our solar system that are consistent with the nebular
theory.
24) Describe the type of extrasolar planet that has been most commonly found.
25) Most of the mass of the solar system is found in the __________.
26) A ________ planet is a relatively small body formed in the inner part of the solar system from condensation
of metallic elements and rocky compounds.
27) The chemical composition differences between the planets are basically the result of the fact that different
elements condense out of gas at different __________________.
28) Early in the history of the solar nebula, small condensation nuclei grew rapidly in size by the process of
__________________.
29) While some Kuiper belt bodies are similar in size to the largest asteroids, we expect the outer bodies to
contain a lot more ________ than the closer asteroids.
30) The age of the solar system, of 4.6 billion years, is determined from dating of __________________.
31) Moon rocks and meteorites all give us an age of about ________ billion years for the solar system.
32) Briefly outline the theory or hypothesis which best explains the origin of the solar system and explain how
the observable properties of the solar system are related to its process of formation.
33) How long did the heavy bombardment phase of the solar system last?
34) Should the solar system be considered unique? Explain.
35) The ________ planets are large bodies with compositions much like the Sun's.
36) In terms of ________, all the terrestrials are greater than any of the Jovians.
37) The composition of asteroids is ________, like the terrestrial planets.
38) The composition of comets is ________, much like the moons of the Jovians.
39) Explain why the early Earth did not form with water, and how it gained it later in its formation.
40) Briefly describe the modern theory of how our Moon formed and discuss the evidence supporting the giant
impact theory.
41) Suppose you discovered a meteorite that contains small amounts of potassium-40, which has a half-life of
1.3 billion years, and its decay product argon-40. You determine that 1/16 of the original potassium-40 remains;
the other 15/16 has decayed into argon-40. How old is the meteorite? Based on your answer, where is this
meteorite probably from?
42) Explain how the age of a rock can be determined by radiometric dating.
43) True or False: All the planets in the solar system have at least one moon.
44) True or False: All four of the giant outer planets—Jupiter, Saturn, Uranus, and Neptune—have rings.
45) According to the nebular theory, how did the Kuiper belt form?
46) According to the nebular theory, how did the Oort cloud form?
47) What is comparative planetology, and what is its basic premise?
48) Briefly summarize the differences between terrestrial and Jovian planets.
49) The region outside the orbit of Neptune in which a large number of objects composed of rock and ice circle
the Sun not far from the plane of the ecliptic is called __________________.
50) True or False: The more massive planets in the solar system tend to be less dense than the lower mass
planets.
51) The planetary system was probably formed from three different categories of material with different
condensation temperatures (the temperature at which the material melts), gases, ices, and rocks. Which is the
correct order of these materials, in increasing condensation temperature?
Unit 5: Review Game Answers
1) It is a thousand times more massive than all the planets combined containing 99.9% of the mass of the solar
system.
2) This is the amount of time it takes for the amount of a radioactive substance to decrease by half.
3) The nucleus of radioactive atoms contains a mix (ratio) of protons and neutrons that is not stable.
4) Mars.
5) Uranus
6) They were produced inside stars.
7) Venus.
8) hydrogen and helium
9) in the asteroid belt between the orbits of Mars and Jupiter
10) Asteroids are rocky bodies and are denser than the comets, which are made of icy material.
11) size and solid surface similar to terrestrial planets; distance and density similar to Jovian planets
12) the Kuiper belt.
13) As the cloud shrank, its gravitational potential energy was converted to kinetic energy and then into thermal
energy.
14) Particles grew by colliding and sticking together.
15) 98 percent
16) In the inner part of the nebula only metals and rocks were able to condense because of the high
temperatures, whereas hydrogen compounds, although more abundant, were only able to condense in the cooler
outer regions.
17) They were formed by condensation and accretion in a disk of gas around the planet.
18) was stronger than it is today.
19) They were large enough so that their gravity could attract more material and they grew larger.
20) The nebula spins faster, flattens into a disk and heats up.
21) They are leftover planetesimals that never accreted into planets.
22) comets that impacted the earth.
23) (a) All planets orbit the Sun counterclockwise when seen from above the earth's North Pole. (b) All
planetary orbits lie nearly in the same plane. (c) Almost all planets travel on nearly circular orbits. (d) The
spacing between planetary orbits increases with distance from the Sun. (e) Most planets orbit in the same
direction in which they rotate, counterclockwise. (f) Almost all moons orbit their planet in the same direction as
the planet's rotation and near the planet's equatorial plane. (g) The Sun rotates in the same direction in which the
planets orbit.
24) They are mostly “Hot Jupiters”, which are large Jovians with orbits more like the terrestrial planets.
25) Sun.
26) terrestrial
27) temperatures.
28) accretion.
29) ice
30) meteorites.
31) 4.6
32) A large nebula began to collapse gravitationally. As it did so, it began to spin faster, and flattened into a
disk and heated up. Planetesimals were formed by accretion of small particles that collided & stuck together
growing larger. The greater gravity of planetesimals attracted more materials and they grew larger, forming
planets. Leftover debris became asteroids and comets.
All the orbital and rotational motions can be explained as preserving the original rotation of the nebula from
which the solar system formed. Accretion explains planetary isolation. Temperature differences explain
differentiation and irregularities can be explained by collisions during the planetesimal era.
33) several hundreds of millions of years.
34) The solar system is unique in the sense that there is certainly none just like it, just as each person is unique.
However, the processes which formed the solar system are believed to be common throughout the universe, and
so there are probably many similar solar systems. So far, the ones found have had Jovian planets in more
eccentric orbits and closer to their stars in general than in our case.
35) Jovian
36) density
37) rocky
38) icy
39) Earth, and all terrestrial planets, formed inside the frost line from rocky and metallic planetesimals. The
temperature of the solar nebula was too hot for water ice to exist and the earth was too small to hold onto a
substantial atmosphere of hot gases. Earth gained its water later during the heavy bombardment phase when
water-rich planetesimals that formed beyond the frost line were scattered into the inner solar system,
predominantly through gravitational encounters with Jupiter, and impacted the earth.
40) The Moon formed from a giant impact of a Mars-size object with the earth. This impact destroyed the body
and blasted material from the Earth’s mantle into orbit. This material eventually coalesced to form the Moon.
Three pieces of evidence are:
 the composition of the Moon is similar to that of the earth’s outer layers,
 the Moon is depleted of easily vaporized materials, as we would expect from the heat of an impact
 computer simulations show that the Moon could really have formed this way
41) To reach a fraction of 1/16, the meteorite has been through four half-lives, which means it is 4 × 1.3 billion
= 5.2 billion years old. Since this is older than the solar system, it is probably a rock from interstellar space.
42) The minerals in rocks contain small amounts of radioactive isotopes (for example carbon-14 or potassium40). Over time, these parent isotopes decay into a different, stable element, the daughter isotope. By precisely
counting the number of parent and daughter atoms within a rock, and knowing the decay time (the half-life) of
the parent, the age can be determined.
43) FALSE
44) TRUE
45) It is made of planetesimals that formed beyond Neptune's orbit and never accreted to form a planet.
46) It is made of planetesimals formed in the outer solar system that were flung into distant orbits by encounters
with the Jovian planets.
47) Comparative planetology is the approach we use to study and understand our solar system. It involves
comparing the worlds of our system, including planets, moons, asteroids, and comets, to one another. Its basic
premise is that the similarities and differences among the worlds can be traced to common physical processes.
48) Terrestrial planets are metallic or rocky in composition, close to the Sun, have higher average density, have
a solid surface, are warmer at the surface, and have few if any moons. Jovian planets are gaseous in
composition, lower in density, have no solid surface, are farther from the Sun, and have rings and moons.
49) the Kuiper belt
50) TRUE
51) gases, ices, rocks