How big is our universe? This Grade 7 science learning station activity explores Earth's place in the universe by comparing the sizes and distances of objects across the solar system and beyond. Students work with kilometres, astronomical units (AU) and light-years to investigate cosmic scale, interpret astronomical observations and recognise the enormous differences in distance between celestial objects.

Explore the Scale of Space

Understanding the universe requires more than knowing the names of planets and stars. Students examine how astronomers describe and compare objects separated by vastly different distances. Through the station activities, they explore:

• Comparing astronomical sizes and distances within the solar system and beyond.
• Using kilometres, astronomical units and light-years as measurements of cosmic distance.
• Interpreting real astronomical observations to recognise differences in cosmic scale.
• Exploring orders of magnitude and how dramatically distances and sizes change across the universe.
• Explaining how an object's size and distance influence what astronomers can observe and how they represent the universe.

What Is Included?

This resource is organised around a learning station approach, with materials for recording, exploring and reviewing student learning.

• Station recording sheet: Provides a place for students to record their station work.
• Station cards: Present the activities and information students use to explore cosmic scale.
• Station wrap-up: Provides an opportunity to bring together ideas from the station experience.
• Answer Key PDF with Teacher Guide: Includes the answer key alongside learning objectives, teaching tips, discussion questions and common mistakes to watch for.

Putting Cosmic Scale into the Classroom

Set up the learning stations for students to explore Earth's place in the universe through structured science activities. Students can work through the station cards, record their observations and responses on the recording sheet, and complete the wrap-up to consolidate their thinking.

The teacher guide supports lesson preparation and classroom discussion. Its teaching tips and common mistakes provide useful guidance when introducing unfamiliar astronomical measurement units, while the discussion questions help extend conversations about what scientists can observe across enormous distances.

Why This Resource Matters

Cosmic scale can be difficult for Grade 7 students to picture because familiar everyday measurements are not sufficient for describing the universe. Comparing kilometres, astronomical units and light-years gives students different ways to represent distances at different scales. Interpreting astronomical observations also connects measurement to the real work of astronomers.

For teachers covering Earth's place in the universe, this resource brings measurement, scientific observation and astronomical scale together in one station-based classroom experience. The included answer key and teacher guidance provide additional support for delivering the activities and discussing the science behind them.

Subject: Grade 7 Science
Topic: Earth's Place in the Universe
Curriculum framework: NGSS