astronomy exam 3

The Great Red Spot, Jupiter's most prominent storm system, has a diameter that is approximately ________ times Earth's diameter.

2

If you start with 16 atoms of a parent radioisotope, after how many half-lives will only one atom of the parent remain, on average?

4

What is the age of our solar system?

4.6 billion years

Which giant planets have rings?

All of them

What sort of liquids do astronomers expect to exist on Saturn's moon Titan?

Lakes of methane, ethane, and other hydrocarbons

Identify causes of erosion of a planet or moon's surface

Moon is exposed to bombardment by meteorites, which change the surface. One little spacerock could easily wipe out a footprint on the moon with earth, eind and water cause erosion

Two years after first being observed, astronomers reported that Saturn's rings vanished. What happened to them?

The rings lined up with Earth, and they were too thin to be observed

Summarize the theory of plate tectonics, and how it can be applied to other planets

The theory of plate tectonics states that the Earth's solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. ... Thus, at divergent boundaries, oceanic crust is created.

Why did the terrestrial planets lose the majority of the gases in their primary atmospheres?

They were too hot and their escape velocities too low to hold onto them

Without the ozone layer, life on Earth would be in danger from increased levels of ________ radiation.

UV

What is the main difference between "super-Earths" and "mini-Neptunes"?

a gaseous mini-Neptune would not be hospitable to life as we know it. On the other hand, a super-Earth with water and other biologically enabling chemistries could serve as a thriving extraterrestrial abode.

Which of the following can be used as an indicator of the age of a moon's surface?

all of the above

Jupiter's mass is _______ times more than the mass of all the other planets in our Solar System combined.

around 2

Differentiate the terms meteoroid, meteor, meteorite, and asteroid

asteroid: a large rocky body in space in orbit around the sun meteoroid: musch smaller rocks or particles in orbit around the sun meteorite: If a small asteroid or large meteoroid survives its fiery passage through the Earth's atmosphere and lands on Earth's surface, it is then called a meteorite. meteor: When meteoroids enter Earth's atmosphere (or that of another planet, like Mars) at high speed and burn up, the fireballs or "shooting stars" are called meteors.

How many moons are known in the Solar System?

at least 150

The colors of the cloud bands on Jupiter and Saturn are due primarily to differences in their _

chemical compositions

Which of the following will remove ("smooth out") features on a planet's surface?

decay of radioisotopes within the planet

According to the following figure, as you increase in altitude in Earth's atmosphere, the atmospheric pressure

decreases; decreasing

Of the following methods, the age of the Solar System can be determined most accurately by ______

erosion

As a group, the giant planets all rotate ________ terrestrial planets

faster than

From what are secondary craters made from?

formed by fragments ejected by a hypervelocity impact that formed a larger (primary) impact crater.

Auroras are caused by _____

gases fluorescing in the atmosphere because of collisions with solar wind particles.

What could have caused the planets to migrate through the Solar System?

gravitational pull from the sun

Summarize how the size, shape, and number of impact craters on a planet or moon provide information on that planet's history.

if it has many craters, it's probably much older

Venus' slow retrograde (backward) rotation is most likely due to __

impact

outline the process of impact crater formation

impact craters, are formed by powerful volcanic explosions. Such outbursts can be violent enough that once the eruption is over, the volcano collapses in on its empty vacant magma chamber and forms a caldera, or volcanic crater.

How do regular moons orbit in comparison to their planet's rotation?

in the same direction

How does the fraction of oxygen in Earth's atmosphere today compare to what it was 3 billion years ago?

it has significantly increased.

All the giant planets except ________ experience seasons

jupiter

Which giant planet has the most prominent band structures?

jupiter

Which of these planets has a composition that is most like the Sun?

jupiter

We have direct evidence for the recent existence of water on the surface of which terrestrial object?

mars

Mars, Venus, and Earth are much less heavily cratered than Mercury and the Moon. This is explained by which fact?

mars, venus, and earth were geologically active longer than mercury and the moon.

The only planet(s) without a moon is (are) _________.

mercury and venus

Space rocks less than 100 m in diameter, when they burn up in the atmosphere, are called ______

meteor

Space rocks less than 100 m in diameter, when they hit the ground, are called _______

meteoroid

Continental drift occurs at a typical rate of a few ______

mm/yr

The giant planets are made primarily of

molecular hydrogen and helium

Which planet receives the least amount of energy from the Sun?

neptune

Which terrestrial planet has rings?

none

Which of the following planets has an average density that is less than that of liquid water?

saturn

The best way to use a telescope to look for life on other planets is to ______

search for absorption from oxygen in their atmospheres.

Weather is the ________ state of the atmosphere, while climate is the ________ state of the atmosphere

short; long

The amount of carbon dioxide in Earth's atmosphere has been increasing over the last 50 years because of _____.

the burning of fossil fuels.

Each halogen atom, such as chlorine, fluorine, and bromine, in Earth's atmosphere contributes to ____

the destruction of ozone over decades and centuries.

Hurricanes are powered by _______.

the heat of vaporization of water.

Which of these observations would allow you to measure the mass of a planet?

the orbit of one of that planet's moons

Heating from _____ causes the top of Earth's stratosphere to be warmer than the bottom

the ozone layer absorbing UV light

Flows of material surrounding Martian craters suggest ______

the presence of water in surface rocks

The shape of Earth's magnetosphere is modified by __

the solar wind

What is the most likely reason that a planet's rings would reflect more than 50 percent of the sunlight they receive?

they are made of ice

Which of the following is a characteristic of irregular moons?

they are much smaller than all of the known planets

Large-scale winds are generated on Earth primarily because of _____

uneven heating of the surface and rotation of the planet.

Assuming that a planet's axial tilt is the most important factor influencing its seasons, then ________ has the most extreme seasons of any planet in the Solar System

uranus

Which of the following is a factor that helps explain Earth's lack of craters compared to the Moon?

wind erosion