Solar System: Rotation, Revolution, Moon Phases, Tides, and Planets

Comprehensive practice flashcards covering Virginia Science Standards 4.7 and 4.8, including Earth rotation and revolution, causes of seasons, the Moon's phases, ocean tides, and the order, relative sizes, and characteristics of the planets.

What is Earth's rotation, and how long does one complete rotation take?

Rotation is the spinning of Earth on its axis, and one full rotation takes $24\,\text{hours}$.

What daily cycle is caused by Earth's rotation?

Day and night.

How long does Earth take to complete one full revolution around the Sun?

Around $365\frac{1}{4}\,\text{days}$.

Why is an extra day added to the calendar every $4\,\text{years}$ as a leap year?

Because we take the extra $\frac{1}{4}$ day from each of the previous four years and combine them into one extra day.

What two factors cause the Earth to experience seasons?

Earth's axial tilt and its revolution around the Sun.

Toward which celestial object does Earth's axis always point throughout its revolution?

The North Star.

Why are temperatures milder during spring and autumn compared to summer and winter?

Because the Sun's rays are not hitting either hemisphere directly.

In this orbital diagram, which letter shows Earth positioned for summer in the Northern Hemisphere?

Position A (where the Northern Hemisphere is tilted directly toward the Sun).

What are the diameter, age, and composition of the Sun according to the lecture notes?

The Sun has a diameter of $1.39\,\text{million km}$ ($864{,}400\,\text{miles}$, or $110\,\text{times}$ the diameter of Earth), an age of $4.6\,\text{billion years}$, and is made of hot gases (hydrogen and helium).

What are the diameter, position, and age of Earth?

Earth has a diameter of $7{,}926\,\text{miles}$ ($12{,}756\,\text{km}$), is the $3\text{rd}$ planet from the Sun, and is $4.54\,\text{billion years}$ old.

What are the size and age of the Moon relative to Earth?

The Moon is $\frac{1}{4}$ the diameter of Earth ($2{,}159\,\text{miles}$ or $3{,}475\,\text{km}$ across) and is $4.5\,\text{billion years}$ old.

Which historical model of the solar system is depicted here, and who believed in it?

The Geocentric Model (Earth-centered), which was believed by Ptolemy and Aristotle over $2{,}000\,\text{years}$ ago.

What observational evidence convinced Galileo to support Copernicus's Heliocentric Model?

Galileo observed moons orbiting Jupiter using a telescope, proving that not all celestial objects orbit the Earth.

How long does it take the Moon to orbit the Earth, and how long does it take from one new moon to the next?

It takes $27.3\,\text{days}$ to orbit Earth, and $29.5\,\text{days}$ to complete the cycle from new moon to new moon.

In lunar phases, what do the terms 'waxing' and 'waning' mean?

'Waxing' means the lit portion is getting bigger, while 'waning' means the lit portion is getting smaller.

What percentage of the Moon is always illuminated by the Sun?

$50\%$\text{ of the Moon is always lit by the Sun}.

In which direction does the Moon rotate and revolve around Earth?

In a counterclockwise direction.

Approximately how many days occur between each consecutive moon phase?

Approximately $3.5\,\text{days}$.

What causes ocean tides on Earth, and why does the Moon exert a stronger tidal force than the Sun?

Tides are caused by the gravitational pull of the Moon and the Sun on Earth's waters; the Moon has a greater effect because it is much closer to Earth.

What is meant by the term 'tidal range'?

The difference in water level between high tide and low tide.

What type of tide is shown in this diagram, and at which moon phases does it occur?

Neap Tide; it produces the smallest tidal range and occurs during the First Quarter and Third/Last Quarter moon phases when the Earth, Sun, and Moon form a $90^\circ$ angle.

What type of tide is shown in this diagram, and at which moon phases does it occur?

Spring Tide; it produces the largest tidal range and occurs during the New Moon and Full Moon phases when the Sun, Moon, and Earth align.

In the Bay of Fundy, what can the difference between high and low tides reach?

As much as $20\,\text{m}$ (about $66\,\text{ft}$).

Which four planets are classified as inner terrestrial planets, and what are their shared characteristics?

Mercury, Venus, Earth, and Mars; they are rocky, have thin atmospheres, have few or no moons, have shorter revolutions, and are smaller in size.

Which four planets are classified as outer gas giants, and what are their shared characteristics?

Jupiter, Saturn, Uranus, and Neptune; they are huge, gaseous with no solid surface, cold, have longer revolutions, often have several moons, and all have rings.

What is the order of the eight planets starting closest to the Sun?

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

What is the order of the eight planets from biggest to smallest?

Jupiter, Saturn, Uranus, Neptune, Earth, Venus, Mars, Mercury.

What is the order of the eight planets from smallest to largest?

Mercury, Mars, Venus, Earth, Neptune, Uranus, Saturn, Jupiter.

Why does Venus have high surface temperatures despite being the second planet from the Sun?

It has a permanent blanket of clouds that traps thermal energy.

What unique rotational characteristic distinguishes Uranus from the other planets?

Uranus spins on its side.

Why are Earth and Venus sometimes referred to as 'sister planets'?

They are very similar in size and mass.

How large is Jupiter compared to Earth, and what causes its colored cloud patterns?

Jupiter is $11\,\text{times}$ larger than Earth, and its colored cloud patterns are caused by enormous storms in its atmosphere.

Why does planet Neptune appear blue in color?

Neptune appears blue because of the composition of its atmosphere.