UScore Academy · Science projects

Build a solar-system scale comparison

MS-ESS1-3 · Two 45-minute sessions

MS-ESS1-38th grade anchorTwo 45-minute sessions

Can one drawing show both planet sizes and orbital distances accurately?

Submit: An evidence record, explanation and revision.

Related lesson: Earth's Place in the Universe

This is a teacher-led extension beyond the short lesson. The task supplies a performance opportunity; completion alone does not certify mastery, full NGSS coverage or state alignment.

Teacher review guide

Build the idea

Planet radius and distance from the Sun are different quantities. A scale model uses the same conversion within each quantity, clearly labeling when separate scales are necessary. Orbital distances here are averages, not a claim that planets remain at one exact separation from Earth.

Science / engineering practice

Analyzing and interpreting data

Core idea

Solar-system objects differ greatly in size and distance

Crosscutting concept

Scale, proportion and quantity

Evidence and model inputs

Rounded NASA-based values: Earth radius 6,371 km, average Sun distance 1 AU; Jupiter radius 69,911 km, 5.2 AU; Neptune radius 24,622 km, 30 AU. For a distance scale of 1 AU = 10 cm, place each planet’s orbit distance from the Sun. For a size scale of Earth radius = 1 cm, calculate the other radii separately. Check the linked NASA source and record rounding.

Keep actual observations, published findings and invented model cases labeled separately. If a source or required equipment is unavailable, pause that part with a teacher; do not invent results.

Materials and preparation

Paper, graph paper or spreadsheet, and the linked readings.

Grade-level scope

Analyze object properties and scale; advanced orbital mechanics are not required.

Do the work

  1. Make a labeled data table and distinguish radius, diameter and average orbital distance.
  2. Calculate each model distance in centimeters and each model radius in centimeters.
  3. Draw the distance model and size comparison separately with explicit scale labels.
  4. Explain why an attractive poster may exaggerate planet sizes relative to spacing.
  5. Choose one pair, state its size and distance ratios, and explain one limitation of the model.

Learner worksheet

Write on paper or type here and print. Entries stay in this page’s memory and are lost when you leave or reload; they are not saved or submitted.

Check your reasoning

  1. Where is Neptune on the distance scale?
  2. What is Jupiter’s model radius?
  3. Is Neptune 30 times Earth’s radius?
  4. Can the two scales be silently combined?

Teacher review guide

Review the actual deliverable and discuss the reasoning. For each criterion, use 0 when evidence is absent or fundamentally incorrect, 1 when partly supported with a material error or omission, and 2 when accurate, supported and complete for the stated task. Maximum 8 points is a task score, not a proficiency certification. Give feedback and allow revision.

  1. Uses correct quantities, units and rounding.
  2. Calculates and interprets size and distance ratios.
  3. Labels separate scales honestly.
  4. Uses data to explain scale and model limitations.
Answer guidance for the reasoning checks

Where is Neptune on the distance scale?

30 × 10 = 300 cm from the Sun.

What is Jupiter’s model radius?

69,911 ÷ 6,371 ≈ 10.97 cm.

Is Neptune 30 times Earth’s radius?

No. 30 AU describes orbital distance, not size.

Can the two scales be silently combined?

No. Label them or use a single consistent physical scale.

Access, support and extension

Offer read-aloud support, labeled diagrams, larger print or an oral/recorded explanation while preserving the scientific reasoning. A partner or teacher can handle physical manipulation while the learner plans, records and interprets. Use a teacher-provided measured dataset only when its provenance and limitations are explicit; it does not replace conducting an investigation when that is the assessed practice. For greater independence, remove prompts and ask learners to compare a second explanation or test another justified revision.

Sources and standard reference

Instructional text and hypothetical cases are original. Linked source readings supply published evidence where specified. Teachers should judge fit with their course and state requirements.