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63 terms

Planets

STUDY
PLAY
Which of these was the first to be found telescopically?
Ceres
Saturn's rings
the four largest moons of Jupiter
the planet Uranus
the planet Neptune
the four largest moons of Jupiter
About___ of the Earth's crust is covered by water.
70%
The critical part of the atmosphere for protecting life on the ground from excessive ultraviolet radiation is the:
hydrosphere
troposphere
ozone layer
stratosphere
ionosphere
ozone layer
Our understanding of the solar system has come in a way that can best be described as:
constant since prehistoric times
slow and steady since the discovery of the telescope by Galileo
erratic, with spurts when new planets were found
steady until the last decade, when the decline in the space program slowed it a great deal
explosive, with us learning more in the past few decades than in all previous history
explosive, with us learning more in the past few decades than in all previous history
Without the greenhouse effect operating in our atmosphere,
A) we would not have to worry about any warming problems in the future
B) Earth would have an average temperature of -23 degrees Celcius
C) the ice in the polar regions would have melted long ago
D) the ozone layer would not be weakening
E) the Earth would have become much more like Venus long ago
Earth would have an average temperature of -23 degrees Celcius
The Dynamo theory is?
Magnetic fields are generated by rapidly spinning, fluids made of hot magnetic materials in planetary interiors
What is density?
Mass divided by volume
The formation of the hydrosphere allowed most of the ____ to be removed from our atmosphere, compared to the present atmospheres of Mars and Venus
carbon dioxide
When we say that our world is differentiated, we mean that:
the iron and nickel core is denser than the silicate mantle and crust
This is NOT a way that terrestrial and jovian planets differ.
Jovian orbits are more eccentric than terrestrials, and farther off the ecliptic
What planet has the most eccentric orbit?
Pluto
The plane in which all planets orbit the sun is called the:
Ecliptic
What are the Terrestrial planets?
Mercury, Mars, Venus, and Earth
Two true things about the Earth's continents:
During the age of the dinosaurs all the continents were closer together than they are today. The continents do move, but they so extremely slow.
T/F: All major planets revolve around the Sun counterclockwise
True
T/F: Weather occurs almost entirely in the troposphere
True
T/F: the mass of all the planets combined is less than 1% on the Sun's mass
True
T/F: Discovering a moon around a planet makes it much easier to weigh it, find its mass
True
T/F: All jovians have equatorial rings and at least eight moons.
True
T/F: Asteroids are the densest form of interplanetary debris
True
T/F: Only the Russian Venera satellites successfully landed on Venus and returned photos and data a few minutes before being destroyed by the heat.
True
T/F: The Earth's solid inner core is about the same temperature as the Sun's photosphere
True
T/F: The energy for plate tectonics comes primarily from radioactive decay in our core.
True
T/F: Subduction of higher density oceanic plates under the continents create deep trenches but also volcanic chains
True
The only planet with a mean density less than water is:
Saturn
Beyond the ionosphere, the Earth's_____ extends past the Moon.
Magnetosphere
The____ planets are large bodies with compositions much like the Sun's.
Jovian
The compositions of the asteroids are_____, like the terrestrial planets.
solid
The principal component of Earth's present atmosphere is:
Nitrogen 80% Oxygen 20%
In 1912 Alfred Wegner noted the puzzle-piece fit of the continents_____ and ______, which led to the discovery of plate tectonics.
South America and Africa
Tidal forces acting on the Earth_____ our rotation rate.
Slows, decreases
Currently we know of about how many extra solar planets?
over 100, and growing by the day
What are extra solar planets?
planets orbiting another star
Compared to the density of water, Earth is on average:
about 5 times denser, similar to Mercury and Venus
What gas is the primary constituent of our atmosphere?
nitrogen
In what part of our atmosphere do we live?
Troposphere
T/F: All planets have densities greater than that of water, one gram/cm^3
False
Masses of the planets are easiest to determine if:
they have natural satellites whose motions can be precisely measured
Mercury and Pluto have the largest...
orbital eccentricities
How do the densities of the jovian and terrestrial planets compare?
All terrestrials are more dense that any of the jovians
T/F: Comets densities are higher than those of asteroids
False
Almost all of our atmospheric gases lie in the
troposphere
Name places on Earth where convection is operating on a grand scale, creating conditions important to life on Earth
At the thermal vents in the rift valleys
The oldest rocks on our crust are radioactively dated at about:
4 billion years old
Which body has the greats gravitational on Earth?
the Sun
The region around Earth where the magnetic field traps charged particles is the:
Van Allen Radiation Belts
T/F: of the terrestrial planets, only the Earth has a moon comparable in size to itself
True
T/F: All terrestrial planets have moons
False
T/F: Of all the planets orbits, Venus' is the most circular
True
T/F: All of the jovian planets rotate more rapidly than any of the terrestrial planets
True
T/F: Almost all the oxygen in our atmosphere was produced by life
True
T/F: Asteroids and meteroids are similar, nut asteroids are over 100 meters across
True
T/F:The solar nebula theory predicts that solar systems like ours should be commonplace, with many young stars forming dusty disks around their equators
True
T/F: Differentiated bodies are spherical in shape, having once been mainly molten.
True
T/F: The high temperature of the Earth's core comes chiefly from the radioactive decay of uranium
True
T/F: Collisions between low density continental plates create the tallest mountain chains, such as the Himalayas.
True
T/F: While the Sun has the larger gravitational pull on the Earth, the much closer Moon plays a larger role in creating our tides
True
By itself,_____ makes up about 70% of the masses of all the planets combined
Jupiter
The principal difference between terrestrial and jovian planets is the absence of ______ and helium close to the Sun.
Hydrogen
The compositions of the comets are ____, much like the moons of the jovians
icy
______ is the process which explains how oxygen replaced much of the carbon dioxide in our early atmosphere.
Photosynthesis
The early formation of the hydrosphere allowed much of the _____ gas to dissolve and be deposited as carbonate rocks
Carbon Dioxide
The___________ are two regions of charged particles trapped in the magnetosphere of the Earth, chiefly around the equator
Van Allen Belt