Meet Henrietta Swan Leavitt: The Unsung Astronomer Who Measured the Universe – Great Astronomers Series

As middle school science educators, we strive to inspire curiosity and show students how scientific breakthroughs often come from unexpected places. In this featured video from the Great Astronomers Series, we meet Henrietta Swan Leavitt, the pioneering astronomer whose discovery of the period-luminosity relationship in Cepheid variable stars helped astronomers gauge the size of our universe.

Leavitt’s work transformed how we understand distances in space—yet her story remains less recognized than those of her male counterparts. This video offers a fascinating glimpse into her contributions through clear narration and visuals perfect for the classroom.

Why you should watch—and share—this video:

• It presents historical science through a relatable lens, engaging for middle schoolers.
• It highlights the often-overlooked achievements of a female scientist, supporting diversity in STEM teaching.
• It adds rich context to lessons on astronomy, light, and scientific history.

Classroom Ideas for Teaching Henrietta Swan Leavitt’s Story

1. Quick Pre-Video Engagement Prediction Prompt:
On the board, write: “What do you think it means to ‘measure the universe’?”
Have students jot down ideas before watching. Revisit after the video to see how their understanding changed.
2. Hidden Figures in Science:
Show a list of famous astronomers (Galileo, Hubble, Newton) and ask which ones they’ve heard of. Then introduce Henrietta Swan Leavitt as someone equally important but less known.
3. During-Video Note-Taking and Post Video Discussion Questions
Click here to download a copy of a worksheet your students can use while they’re watching the video.
4. Hands-On Science Tie-In
Star Distance Model:
Have students use a simple light bulb (as a star) and a lux meter or phone app to see how brightness changes with distance. Relate this to Leavitt’s work on Cepheid variable stars.
Light Curve Activity:
Provide sample light curve graphs for Cepheid variables and have students measure the period, then discuss how it relates to brightness.

Henrietta Swan Leavitt’s meticulous work measuring the brightness of Cepheid variable stars may not have made front-page headlines in her lifetime, but it laid the foundation for one of astronomy’s most important breakthroughs—understanding the true scale of the universe. Sharing her story not only enriches your astronomy lessons, it also reminds students that scientific discovery is built on the dedication and insight of many minds, not just the ones in our textbooks.

The next time you teach about stars, light, or the history of astronomy, consider introducing your students to Henrietta. Her story is an inspiring example of how careful observation, perseverance, and a passion for discovery can change our understanding of the cosmos.

Embed this video in your next astronomy lesson, use the classroom ideas above, and help your students discover the hidden heroes of science. If you try these activities, share your experience in the comments below—or pass this post along to another teacher who could use it in their classroom. Let’s keep shining a light on the scientists whose brilliance deserves to be remembered.

Related reading:

Women in Science Resources for Middle Schoolers
Black History Month: Celebrating Contributions of African-American Scientists