identify and compare the physical characteristics of the Sun, Earth, and Moon

Our solar system is made up of the Sun, the planets and other objects in space such as the Moon.

The Sun, Earth and Moon each have unique physical characteristics. Comparing them helps us to learn more about all three. We will start with the Sun. The Sun is the largest space body in our solar system. In fact, it makes up almost 98% of the solar system’s total mass. It is so large that if it were an empty gumball machine, it could hold 1.3 million Earth sized gumballs. That’s a lot to chew on!

The Sun is a star, and like all the other stars we see at night, it is made up of a ball of very hot gases. The Sun looks much larger than any other star, but the Sun is actually a medium-sized star that is much closer to us than any other star, so it only looks bigger to us. The Sun is located in the center of our solar system. Because it is much bigger than anything else in the solar system, it has more gravity. This gravity is what causes the planets to orbit or move around the Sun in pathways.

The Sun is very hot. In fact it is almost 11,000°F. This extreme heat keeps the Sun from having a solid surface. At such high temperatures, everything on the Sun is a gas. The Sun does not have any of the physical land features that are found on the Moon or Earth. But, the Sun does have a few recognizable features. Areas of the Sun that are slightly cooler (but still very hot) show up as darker spots. These darker spots are called sunspots. We can sometimes see sunspots from Earth when we use special equipment. When there are many sunspots on the Sun, a solar flare may occur. Solar flares are eruptions of gas from the surface of the Sun. The Sun has an atmosphere, but it is made up of very hot gases and would not support any kind of life that we know of.

The Moon is very different from the Sun. It is much smaller and much closer to Earth than the Sun. The Moon has no light of its own. It only reflects the Sun’s light. The surface of the Moon is more like that of Earth’s surface. The Moon has a solid, rocky surface, but has no liquid water available. There are craters on the Moon’s surface that can be seen from Earth when special equipment is used. There are also areas like mountains and areas that are flat. However, the surface of the Moon doesn’t change like it does on Earth. Because the Moon has no atmosphere and no liquid water, weathering, erosion, and deposition don’t take place. Landslides, earthquakes and volcanoes also don’t happen on the Moon either. One confusing fact about the Moon is gravity. The Moon does have gravity, but because it is smaller, it has only a fraction of the gravity that we experience on Earth.

We are all more familiar with Earth. Earth is the third planet from the Sun. This is just the right distance to allow for life. The Sun provides Earth with energy and heat needed by life forms. Earth is also the only planet we know of to have an atmosphere containing oxygen and liquid water on its surface. With water and an atmosphere come changes to Earth’s rocky surface. Wind, water and ice cause weathering, erosion, and deposition that continuously change Earth’s surface. Earth’s gravity is not nearly as strong as the Sun’s but it is strong enough to keep the Moon in orbit around the Earth.

• Star
  
• Center of solar system
  
• produces light
  
• largest in size
  
• shaped like a sphere
  
• made of gas
  
• cannot support life
  
• hottest temperatures
  
• gravity
  
• no water

• Has craters
  
• Water in all states, frozen, liquid, and gas
  
• Reflects light
  
• 71% covered in water
  
• shaped like a sphere
  
• made of rock
  
• has life
  
• has an atmosphere so it has weather
  
• gravity
  
• rotates

• has craters
  
• smallest in comparison to E, and S
  
• reflects light
  
• no atmosphere
  
• shaped like a sphere
  
• made of rock
  
• cannot support life
  
• coldest temperatures
  
• gravity
  
• rotates
  
• frozen water

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Track #420297: Sun, Earth and Moon Scavenger Hunt

Annotated by: Denise Ridgway