Properties of the Planets Properties of the Planets in our Solar Systemin our Solar System

(13.10)(13.10)Star TestStar Test

BLM 13.10BLM 13.10

The Solar SystemThe Solar System (p. 418)(p. 418)

Now we are going to take a close look Now we are going to take a close look at the specifics of the solar system.at the specifics of the solar system.

Each planet in our solar system is Each planet in our solar system is unique.unique.

We talked the other day that the Earth We talked the other day that the Earth rotates and revolves:rotates and revolves:

What is this?What is this? How long is it?How long is it?

365 days, this is called an 365 days, this is called an Orbital PeriodOrbital Period..

Orbital PeriodOrbital Period

All the planets have different Orbital All the planets have different Orbital Periods.Periods.

Why do the planets travel in orbits?Why do the planets travel in orbits?

This is only one of many ways to This is only one of many ways to compare the planets. compare the planets.

Properties of the Planets in the Properties of the Planets in the Solar System Solar System (BLM 13.10)(BLM 13.10)

Average distance from the Sun:Average distance from the Sun:

Why average… Why average… orbits not completely round.orbits not completely round.

Orbital Period:Orbital Period:

All planets do not spin together.All planets do not spin together.

Average Diameter:Average Diameter:

Planets have peaks and valleys… Planets have peaks and valleys… even even Earth.Earth.

Time for Rotation:Time for Rotation: What’s rotation?What’s rotation?

Main Substances in the atmosphere:Main Substances in the atmosphere:

Properties of the Planets in the Properties of the Planets in the Solar System Solar System (BLM 13.10)(BLM 13.10)

Mean surface temperature: Mean surface temperature: Why mean?Why mean?Density: Density: What is it?What is it?

Things more tightly compact.Things more tightly compact.1 cm1 cm33 of water is less dense than 1 cm of water is less dense than 1 cm33 of lead. of lead.

Surface Gravity:Surface Gravity:Smaller # means people are lighter on that Smaller # means people are lighter on that planet.planet.

Now, Look at the table to see if any Now, Look at the table to see if any characteristics of other planets are the same characteristics of other planets are the same as the Earth. Are any planets inhabitable as the Earth. Are any planets inhabitable like Earth? Why? like Earth? Why?

Properties of Planets in our Solar Properties of Planets in our Solar SystemSystem

(BLM 13.10a)(BLM 13.10a)

Questions - p. 419Questions - p. 419Answer in Answer in FULLFULL sentences, leave space for extra sentences, leave space for extra

comments. Take you time and comments. Take you time and THINK!THINK!

1. a) Name two planets that scientists think 1. a) Name two planets that scientists think have no atmosphere.have no atmosphere.

Mercury and Pluto have no atmosphere.Mercury and Pluto have no atmosphere.

b) Could the same reasons be used to b) Could the same reasons be used to explain the lack of atmosphere on both explain the lack of atmosphere on both planets? Explain. planets? Explain.

These are the smallest planets and they These are the smallest planets and they have low surface gravities. This helps have low surface gravities. This helps explain the lack of an atmosphere. explain the lack of an atmosphere. Mercury is close to the Sun so its Mercury is close to the Sun so its atmospheric gases have enough energy atmospheric gases have enough energy to escape.to escape.

2.2.Consider all the information in the table:Consider all the information in the table:

a) Which planet appears to be most similar a) Which planet appears to be most similar to Earth? Explain.to Earth? Explain.Mercury, Venus, and Mars are most similar Mercury, Venus, and Mars are most similar to Earth. (Diameter, Density, Surface to Earth. (Diameter, Density, Surface Gravity, and they are relatively close to the Gravity, and they are relatively close to the Sun)Sun)b) Which planets could be grouped as those b) Which planets could be grouped as those that are least similar to Earth? Explain.that are least similar to Earth? Explain.Jupiter, Saturn, Uranus, and Neptune are Jupiter, Saturn, Uranus, and Neptune are least similar to the Earth. (Large, low least similar to the Earth. (Large, low densities, extremely cold and far away from densities, extremely cold and far away from the Sun)the Sun)c) Which planet seems to fit into a category c) Which planet seems to fit into a category by itself? by itself? Pluto has few features in common with the Pluto has few features in common with the other distant planets.other distant planets.

3. Which planets have densities much 3. Which planets have densities much

lower than Earth’s? What can you lower than Earth’s? What can you conclude about these planets?conclude about these planets?

Jupiter, Saturn, Uranus and Neptune Jupiter, Saturn, Uranus and Neptune have low densities. They appear to have low densities. They appear to have similar compositions.have similar compositions.

4. Would the atmosphere on the four 4. Would the atmosphere on the four largest planets support Earth-type largest planets support Earth-type life forms? Explain. life forms? Explain.

Life forms on Earth need oxygen, a Life forms on Earth need oxygen, a gas that is not found in any of the gas that is not found in any of the atmospheres of the four large atmospheres of the four large planets. Thus, these planets would planets. Thus, these planets would not support Earth-like life forms.not support Earth-like life forms.

5. Create a mnemonic sentence to 5. Create a mnemonic sentence to help you remember, in order, the help you remember, in order, the names of the planets.names of the planets.

Ex. “My Very Educated Mother Just Ex. “My Very Educated Mother Just Served Us Nine Pizzas” Served Us Nine Pizzas”

““My Very Elegant Mother Just Stared My Very Elegant Mother Just Stared Until Nobody Played”Until Nobody Played”