Astronomy Chapter 9: Venus

Venus is never seen at midnight because

it is closer to the Sun than is Earth.

Venus' permanent retrograde rotation about its axis results in the planet

having its north pole below the plane of the ecliptic.

How is Venus' rotation best described?

Slow and retrograde

Venus emits a blackbody spectrum characteristic of a temperature near what value?

730 K

How is the surface of Venus primarily observed? Why does it have to be observed this way?

Orbiting satellites using radar, because the surface is permanently obscured by clouds.

Compared with Earth, Venus has a level of plate tectonic activity that is

virtually nonexistent.

Describe the characteristics that prevail on the surface of Venus.

Hot, dry, and dusty

What three features that provide evidence of volcanic activity have been observed on Venus?

Pancake-shaped lava domes, coronae, and shield volcanoes

What keeps the surface of Venus looking so young?

Ongoing volcanism

Venus, Earth, or both? :

Includes the continent-sized regions Ishtar Terra and Aphrodite Terra

Has very few impact craters with a diameter less than 25 kilometers

Venus

Venus, Earth, or both? :

Has plate tectonics

Has many craters with a diameter about 10 meters

Earth

Venus, Earth, or both? :

Surface includes mountains and rolling plains

Has evidence of past volcanic activity

Both

Are coronae present on Venus, the Moon, or both?

Venus only

Does the Moon, Venus, or both have an abundance of craters?

The Moon only

Does the Moon, Venus, or both lack plate tectonics?

Both

Does the Moon, Venus, or both have smooth regions of lava-type rock?

Both

______ are a common feature on Venus. The Hawaiian Islands are a good example of this on Earth.

Shield volcanoes

______ are found on both Venus and Earth. They are the result of upwelling magma pushing up on the surface.

Lava domes

______ on Venus are analogous to rilles on the Moon.

Lava channels

The altitudes of Venus' atmosphere and troposphere as well as the surface pressure and temperature of Venus are all ______ than that of Earth's.

greater

Venus, Earth, or both? :

Oxygen present as a primary component

Water vapor cloud layer

Earth

Venus, Earth, or both?

Carbon dioxide as a primary component

Sulfuric acid cloud layer

Venus

Venus, Earth, or both? :

Polar vortex

Atmospheric jet stream

Both

T/F: There are trace amounts of oxygen present on Venus.

False. There is no oxygen on Venus.

Venus' atmosphere is composed mostly of ________.

carbon dioxide

The ______ layers of Venus are 50 to 150 km above its surface.

coldest

Venus' high surface temperature is due to the ______ effect.

greenhouse

What is Maxwell Mons on Venus?

A huge shield volcano.

Where does a shield volcano sit?

Above a hot spot in the planet's mantle.

T/F: As on Earth, continent-like land masses cover over a quarter of the surface of Venus.

False.

What is the result of the Greenhouse Effect on Venus?

It has raised the surface temperature by hundreds of degrees Celsius.

Earth and Venus are often called sister planets, in which ways are they most alike?

Size, density, and surface gravity.

Which intrinsic property of Venus makes it very reflective of light?

Its clouds

Which property of Venus' atmosphere gave rise to the runaway greenhouse effect?

Composition of atmospheric gases

Venus lacks a planetary magnetic field because

it rotates very slowly.