The Arizona STEM Acceleration Project

SIZE & SCALE OF OBJECTS IN THE UNIVERSE

Size & Scale of Objects In The Universe

A [7-12] Grade STEM Lesson

M. Winters

June 2023

Notes for Teachers

• This is an introductory lesson that I use very early in the year in my high school Astronomy courses.
• This lesson & activity will introduce students to the concept of size and scale of various objects in the universe.
• Teacher will guide students through a series of notes then students will complete an online activity where they will learn about size & scale.

List of Materials

• Projector to display student notes on wall/board.
• Paper copies of the animation activity (1 per student).
• Computer with internet access (1 per student or 1 per pair of students)

Standards

Science:

Plus HS+E.E2U1.16

Obtain, evaluate, and communicate information about patterns of size and scale of our solar system, our galaxy, and the universe.

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Core Ideas:

Physical Science P2 (Objects at a Distance)

Earth & Space Science E2 (Earth & the Universe)

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Ed Technology:

Knowledge Constructor

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Mathematics:

Ratio & Proportion

Objective(s):

Students will be able to describe new & unfamiliar units for measuring distance.

Students will begin to comprehend the vast differences in sizes and scales of objects within the universe.

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Agenda

This lesson and corresponding activity should take approximately 2 hours/class periods.

The lesson begins by guiding the students through the notes on slides 8-22.

After the students have taken notes on the slides, they should move immediately into the animation/activity.

Students will likely NOT finish the activity during that first class period so they should have time to finish during the next period.

Once completed, they activity may be graded or reviewed (or both).

Intro/Driving Question/Opening

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Start the lesson by basically challenging students with what seems like a silly question such as “How large is large, how small is small?”

Ask students if they have any idea how big things really are - then move into the guided notes on the following slides.

SIZE & SCALE�OF OBJECTS IN�THE UNIVERSE

THE PALE BLUE DOT

• In 1990, the Voyager-1 Spacecraft (VERY early deep space probe launched from Earth) turned its camera back towards the Earth and took an amazing photo at a distance of 3.7 billion miles!

“The Pale Blue Dot”

Earth

“The Pale Blue Dot”

Zoomed in on one of Saturn’s rings so the Earth is more visible

THE HUBBLE DEEP FIELD

• One of the most famous photos ever taken by the Hubble Space Telescope is called the “deep field.” This photograph is an area of the night sky approximately the size of a pea that is held out at arms length. There are only two stars in the photograph!

SIZE & SCALE OF THE UNIVERSE

• (((Obtain a whiteboard, towel, & marker)))
• Lets see what you people think in terms of size & scale of the universe.

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• About how big is the Earth (diameter)?
• Diameter ≈ 7923 miles

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SIZE & SCALE OF THE UNIVERSE

• About how far across is the solar system (diameter)?

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• Diameter ≈ 9,114,000,000 miles (to Pluto-ish)

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• Diameter ≈ 930,000,000,000 miles – 9,300,000,000,000 miles. (O.C)

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SIZE & SCALE OF THE UNIVERSE

• About how far across is the galaxy (diameter)?

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• Diameter ≈ 559,000,000,000,000,000 miles

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SIZE & SCALE OF THE UNIVERSE

• How big is the universe?

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• Infinite (maybe). It is impossible to even begin to put a number on the size of the universe (maybe).

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SIZE & SCALE OF THE UNIVERSE

• The numbers are getting way too big to understand and deal with, miles and or kilometers are just too small.

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• We need some more convenient units for measuring distances in the universe.

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NEW UNITS FOR MEASURING DISTANCE

• Astronomical Unit: The average distance from the Earth to the sun.

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• 1 AU = 93,000,000 miles.

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• (((Still actually a really small unit!)))

NEW UNITS FOR MEASURING DISTANCE

• Light Year: The distance a beam of light travels in one year.
• In the vacuum of space, light travels at the speed of light so…
• 1 LY = 5,866,000,000,000 miles
• 1 LY = 9.467x10¹⁵ meters

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• (((Still actually a pretty small unit!)))

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NEW UNITS FOR MEASURING DISTANCE

• Parsec: A unit of distance derived from the parallax movement of a star over the course of a year.
• Don’t worry too much about what that means, just accept it…
• 1 parsec = 3.26 Light Years

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• (((Still kind of a small unit!)))

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NEW UNITS FOR MEASURING DISTANCE

• Since the parsec is actually still pretty small, you should expect to be dealing with numbers in the kiloparsec, megaparsec, & gigaparsec range during this year.
• Good luck!
• (((Do the Scale of Universe Activity)))
• THE END…

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Hands-on Activity Instructions

• This activity is pretty “self-guided” for students. Students may work alone or in pairs by sharing a computer or having one for each student.
• Provide each student a paper copy of the activity, and allow them to access computers and the internet and they should be good to go!

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Link To Class Activity

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Scale of the Universe

Assessment

The assessment is the hands-on animation activity found on slides 23 & 24.

Assessment

Here is a key for the activity

Assessment

Here is a key for the activity

Differentiation

This lesson could be expanded upon, changed, or modified in a number of ways, please feel free to do so.

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Provide key vocabulary with images.

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Allow short answer format to questions or verbal responses as needed.

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Strategically pair students as needed.

Remediation

Extension/Enrichment

A possible extension could be to have students do some basic math with the size and scale of specific objects.

For example students could use the animation to estimate how many times larger than an ant the Empire State Building is and so on…