Lesson 4.3.2

Inner Planets

​

Lesson 4.3.2

Open Ended

When you hear the word, terrestrial, what do you think of?

Open Ended

Word meaning

Terrestrial-of, on, or relating to the earth

How do you think this word relates to astronomy?

• ​The root word of terrestrial is terr, which means "earth" or "land"

• Terrestrial means "Earth-like"

• The first four planets in our solar system are the terrestrial planets.

• They all have similarities to Earth.

• Today we will explore these 4 planets.

Terrestrial

science notebook

Materials

• describe the main features of each of the inner planets

• compare each of the inner planets to Earth and to one another

What we will learn...

Lesson Objectives

Categorize

Options (6)

orbit the sun

enough mass to be round

orbit is clear of debris

have living life

have water

have an atmosphere

What are the three things that a planet must have to be considered a planet?

Yes a planet requirement

Not a planet requirement

Mercury

Venus

Mars

​These are 3/4 of the inner planets. Since we have already explored Earth, we will focus on these 3 inner planets today.

Mercury

Open Ended

Share something you learned about Mercury

• ​1st planet in solar system and closest to the sun

• Looks very similar to the moon with lots of craters.

• fastest planet to orbit sun.

• No atmosphere due to low gravity.

• 3.032 miles in diameter

• mass compared to Earth-0.0553

• Distance from sun= 0.4AU

• Length of day= 59 earth days

• Length of year= 88 earth days

• Temperature- -290 to 800 degrees F

• No moons

Mercury (bolded facts should be in notes)

Multiple Choice

What makes Mercury a unique object in the solar system?

• 
  It is the closest planet to the Sun and has no atmosphere.

• 
  It has an abundance of water on its surface.

• 
  It has the fastest rate of rotation.

Venus

Open Ended

Share something you learned about Venus

• ​2nd planet in solar system

• considered Earth's twin due to similar size

• Has yellow appearance due to carbon dioxide in atmosphere.

• The carbon dioxide creates large amounts of sulfuric acid that damages probes.

• 7,521 miles in diameter

• mass compared to Earth-0.815

• Distance from sun= 0.72AU

• Length of day= 243 earth days

• Length of year= 225 earth days

• Temperature: 900 degrees F due to sun's heat getting trapped in

• No moons

Venus (bolded facts should be in notes)

Multiple Choice

Why is Venus often referred to as Earth's twin planet?

• due to its extreme temperatures

• because of its thick carbon dioxide atmosphere

  
  

• because of its similar size and composition

  
  

Mars

Open Ended

Share something you learned about Mars

• ​4th planet from the sun

• Known as "Red Planet" due to color from rust and dust on the surface.

• Largest canyon system in solar system, 2500 mile long Mariner Valley

• The carbon dioxide creates large amounts of sulfuric acid that damages probes.

• 4,221 miles in diameter

• mass compared to Earth-0.107

• Distance from sun= 1.5 AU

• Length of day= 24 hours 37 minutes

• Length of year= 687 earth days

• Atmosphere consists of carbon dioxide, argon, nitrogen, water

• Temperature: -225 to 70 degrees F

• 2 moons

Mars (bolded facts should be in notes)

​They are all rocky in nature with defined solid surfaces.

​They are all relatively small as seen in the image of all eight planets.

They are all relatively dense because they are made of rock and metal.

​How are the 4 inner planets all similar?

• ​3rd planet from the sun

• 7.296 miles in diameter

• mass 1.00

• Distance from sun= 1 AU

• Length of day= 23 hours 56 minutes

• Length of year= 365 earth days

• Atmosphere consists of carbon dioxide, argon, nitrogen, oxygen

• Temperature: -128 to 134 degrees F

• 1 moons

Earth(bolded facts should be in notes)

Let's Review

What did we learn today...

• features and characteristics of Mercury, Venus, and Mars; and

• the characteristics of the terrestrial planets.

Multiple Choice

How do the terrestrial planets compare to Earth?

• same rocky composition

• same atmosphere

  
  

• same size

• same surface composition

Multiple Select

How do the terrestrial planets differ from Earth?

Choose all that apply

• rocky composition

• atmospheres

  
  

• size

• surface composition

Reorder

Sort the terrestrial planets in order of their distance from the Sun. (remember the saying)

• Mercury

• Venus

• Earth

• Mars

1

2

3

4

• 1
• 2
• 3
• 4

If you want to hear some music inspired by the planets, click on the link on the next page.

Edio | Commonwealth Charter Academy

You can open this webpage in a new tab.

Copy link

Open in new tab