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Planets in our Solar System

Planets in our Solar System

Author: Dave Bonachita


5-ESS1-1. Support an argument that differences in the apparent brightness of the sun compared to other stars is due to their relative distances from Earth.


Rl.3.1 Ask and answer questions to demonstrate understanding of a text, referring explicitly to the text as the basis for the answers.




Students will be able to define the terms:

Orbit- the curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution.
Rotation- the action of rotating around an axis or center.
Revolution- the time taken for a body to go around an orbit and return to its       original position.

Discuss the differences between each planet and the sun and how they rotate on their axis while orbiting around the sun and making a whole revolution.

Anticipatory set: - Start out by saying Twinkle, twinkle, little star, How I wonder what you are.

How I wonder what you are indeed. There are many stars in the sky during the night but what are they? Any guesses? We have a star that is really close to us but unlike most other stars we can only see it during the day. The sun is the closest star to us.


            Use CCD chart to introduce vocabulary.

State each new word and see how many students have heard or never heard of the word before.

Ask for each word’s prediction and what they think it is.

Show them the final/true meaning

Review each word again before moving on.


Each of their desks has been assigned a planet. Ask each desk to choose a representative and bring their planet up when called upon.

Tell them to read the back of their planets that you’ve already written on and have them line up:

Mercury- It’s so hot because I’m the closest to the sun
Venus- You think you’re hot? I’m the hottest because of my very thick atmosphere that traps heat. Sun! My king! I’m your Venus; I’m your fire, your desire.
Earth- Whoa calm down there Venus. I may not be as hot as you even during summer but I can at least hold a hospitable environment where life forms can coexist.
Mars- Well I have the tallest mountain in the solar system. My Olympus Mons makes your Mount Everest look like a pimple
Jupiter- HEY! If you’re talking about size, I’m your planet! I’m the biggest planet out here!
Saturn- whoa. Calm down there Jupiter before you get all gassy. You may be the biggest planet but I’m the most beautiful. I can prove it because I’m already engaged. See my big beautiful ring made of rocks, ice, and dust?
Uranus- What are you talking about gassy? Aren’t the last four of us gassy? Jupiter, Saturn, me and Neptune.
Neptune- Did someone call me? I see you’re still orbiting sideways as usual Uranus.
Pluto- What am I doing here? I’m not a planet.

Guided practice:

Tell the students who just finished volunteering to rotate on their axis and follow their orbit to make a full revolution around the sun (you) and then back to their seats one at a time.
Ask students to think in their groups about what order the planets have according to their distance from the sun.
As they answer, take each picture/name of the planets from each group and tape them to the board.


Independent practice

Students will write and draw in their journals about what they learned.


Finally, as a class they will think pair and share what they learned during the lesson


Teacher will monitor around the class during the guided practice and the independent practice.

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Order of the planets

The order of the planets based on the distance they orbit from the Sun is as follows:

Mercury – 57 910 000 km (0.38 astronomical unit, or AU) from the Sun
Venus – 108 200 000 km (0.72 AU) from the Sun
Earth is 149 600 000 km (1.00 AU) from the Sun
Mars is 227 940 000 km (1.52 AU) from the Sun
Jupiter is 778 330 000 km (5.20 AU) from the Sun
Saturn is 1 429 400 000 km (9.54 AU) from the Sun
Uranus is 2 870 990 000 km (19.218 AU) from the Sun
Neptune is 4 504 000 000 km (30.06 AU) from the Sun.

If you were to identify planets in order of their size, the largest would be:

Jupiter at 142 984 km at its equator,
Saturn at 120 536 km
Uranus is 51 118 km
Neptune 49 532 km
Earth 12 756.3 km
Venus 12 103.6km
Mars 6 794 km
Mercury 4 880km

The disparity may be understandable as Saturn and Jupiter are gas giants, while Uranus and Neptune are ice giants. The remaining planets are smaller by virtue of their having solid rocky surfaces. The size of Jupiter is such that it could fit all the other planets inside it.

Defining the order of the planets by their discovery date can be subjective.

Bright planets like Venus have been observed since ancient times. Mercury, however, has the earliest recorded observations that date to at least 400 BC; Greek astronomers thought the planet was two separate objects. Mars was always visible to the naked eye; in 400 BC it was known as the Star of Death to Babylonians because of its red glow showed up brightly the black night sky. The discovery of Venus is credited to Pythagoras in the 600 BC, but the mathematician thought it orbited Earth. In 1610, Galileo was the first person to observe the moons around Jupiter. He was also the first person to observe Saturn through a telescope that year, although ancient civilizations had known of the planet too. Uranus was discovered by William Herschel in 1781, making it the first planet to be discovered in modern times. Later, Neptune was observed by Galle and d’Arrest in 1846 thanks to predictions made from calculations based on the locations of Jupiter, Saturn and Uranus. It’s not possible to determine when Earth was discovered, although mankind realized in the 16th century that it was just another planet and not the center of the universe.

Order of the planets by the numbers of the moons:

Earth is not the only planet to have a moon in its orbit. Here is list ordered by the number of the moons:

Jupiter heads the list with 63 known satellites.
Saturn has 34 moons that have been named
Uranus has 27 (21 named)
Neptune has 13 moons, 6 of which are unnamed and Mars has 2 moons.
Earth has 1 moon.
Venus and Mercury have no moons.

Dwarf planets ordered by the size are:

Eris 2400 km at diameter
Pluto 2306 km
Makemake 1500 km
Haumea 1150 km
Ceres 974.6 km

Dwarf planets ordered by the distance from the sun:

Ceres 413 700 000 km
Pluto 5 906 380 000 km
Haumea 6 484 000 000 km
Makemake 6 850 000 000 km
Eris 10 210 000 000 km

Source: Order of the planets. (n.d.). Retrieved July 29, 2015, from

Order of the planets picture

Source: Order of the planets. (n.d.). Retrieved July 29, 2015, from

This video includes a song which teaches about the order of the planets from the sun.

Source: Outer Space: "We are the Planets," The Solar System Song by StoryBots. (n.d.). Retrieved July 29, 2015, from

The Big Question

Create a sentence using the first letters of each planet in order as a guide to help you recall or remember the order of the planets.

Example: Many Very Elderly Men Just Snooze Under Newspapers.

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