Astronomy Chapter 5 Questions

What is the formula for Average Density?

Total Mass/Total Volume

What types of [man-made] chemicals deplete the Ozone Layer?

Chemicals that are rich in Bromine or Chlorine

What is another name for the Ionosphere?


What about a planet can be determined by studying the deflection of [seismic] waves?

The structure of a planet's interior

What causes the formation of Rille?

The collapse of a solidified lava tube

How were the highlands created?

By flows of lava that filled low-lying basins (enormous craters)

How are the heights and depths of Venus's hills and valleys determined?

By measuring the time delay of radar echoes

Which planet has no seasons?What is the reason for this?

-Venus-Because its axis within 3 degrees of being perpendicular to the plane of its orbit around the Sun

High in the eastern sky before sunrise, ________ is also called the "morning star".


_______ is the most iron-rich planet in the solar system.


Which planet is closest to the sun?What is its angle from the sun?

-Mercury-Angle from the sun (elongation) is less than 28 degrees

How long was the day when earth first formed?

Between 5 and 10 hours

What are the 4 reasons why moon-quakes occur?

1) Impacts2) Motion of the lunar surface due to changing tides created by Earth's gravity3) Expansion and contraction due to heating and cooling of the Moon's surface4) Other activity inside the Moon, which is still under investigation

What are magnetic fields created by?

Electric charges in motion

What provides the energy that drives the motion of the tectonic plates?

The heat and molten rock inside of Earth

What/where did our oxygen come from?

From oxygen-rich molecules, like carbon dioxide, being broken apart by the Sun's radiation

Which planets don't have moons?

Mercury and Venus

What do high albedos imply?What are they covered by?Which planets have these?

-Imply bright materials exposed to space-Completely covered by clouds, which scatter sunlight back into space very efficiently-Venus, Jupiter, Saturn, Uranus, and Neptune

What do low albedos result from?Which planets have these?

-Result from dark, dry surfaces, or from a mixture of light and dark surfaces exposed to space-Mercury, Earth, and Mars

For solar system objects, spectra are provided primarily by what?

Sunlight scattered off the surface or clouds that surround each object

What is the formula for atmospheric pressure?


What main gases absorb infrared radiation?

Water, carbon dioxide, and ozone in the air

Where do earthquakes and volcanoes tend to occur?

At the boundaries of earth's crustal plates

A magnetic field extends through Earth's surface and out into space. What does this result from?

The convection of molten metal inside Earth combined with the planet's rotation

When do the northern lights (aurora borealis) and the southern lights (aurora australis) occur?

When the Van Allen Belts overload with particles

What percentage of light that hits the moon is scattered?


What does Mercury having a 3-to-2 spin orbit coupling mean?

It undergoes 3 sidereal rotations while undergoing two revolutions around the Sun

Where can you find ice on Mercury?

Near its poles, in craters permanently in shadow

Which planet has the coldest temperature?


What are Venus's clouds composed of?

Droplets of concentrated sulfuric acid

What percentage of Venus is covered by volcanic plains and gently rolling hills?

More than 80%

Which planet is a 'one-plate planet'


Which planet experiences earth-like seasons?


Where does the chemical reactivity of the Martian regolith come from?

The Sun's ultraviolet radiation and from electrical activity inside dust devils

What is Earth's atmosphere mainly comprised of?

Nitrogen & Oxygen

What are the 6 regions of Earth?

-Inner core-Outer core-Mantle-Hydrosphere-Atmosphere-Magnetosphere

The ___________ is the level of Earth's atmosphere that reflects radio waves back to it.

Thermosphere (Ionosphere)

Which travels faster, P-waves or S-waves?


What type of wave is absorbed when it travels into a liquid?


What determines the speed at which a seismic wave will travel?

Speed of waves depend on density of material they pass through

_______ _______ introduced the idea of "continental drift".

Alfred Wegener

The moon has a sidereal period of ___ days synodic period ___ days.

Sidereal- 27.3Synodic- 29.5

In what direction does Venus's south pole face?


Which planets exhibit retrograde rotation?

Mercury & Venus

_______ (1990) mapped Venus in radar.


What percentage of Venus's surface are volcanic plains?


The planet _______ contains the largest shield volcano ________, and the largest valley ________ in our solar system.

-Mars-Olympus Mons-Valles Marineris