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How Big Is The Universe?

Transcript-How Big Is the Universe
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How big is space? Who helped discover this? 🌌 Join us as we talk to astronomer Karen Masters. She introduces us to Henrietta Leavitt, a “computer” before computers who helped scientists rethink the size of our universe. ⭐

Learn more about how Karen uses Henrietta's work in our bonus interview episode, available on Patreon!



Photo of Karen Masters

Dr. Karen Masters is a professor of astronomy and physics at Haverford College. She researches galaxies and investigates the mapping of our Universe.

Karen is also a member of the Galaxy Zoo project, a part of Zooniverse's collection of Citizen Science Projects. On Galaxy Zoo, you can help scientists identify objects in the sky, through digital images - and contribute to real scientific research!


Artwork for Cataloging the Universe. Pictured is a galaxy and stars.

As you may remember from the start of the episode, Tumble just released “Cataloging the Universe,” a seven-part interactive series where you’ll get to travel along as we tell the story of how we learned just how big the universe is.

Plus, it’s interactive! Each episode - or lesson - in this series contains activities to complete while you listen. Plus, you’ll get discussion questions, graphic organizers, and a star journal to keep your observations in. This course is intended for students in grades 3-5, but any age with the help of a parent, caregiver, or teacher!

Spoiler alert! Karen and Henrietta will make an appearance! Click here or on the series artwork to learn more!


Black and white photograph of Henrietta Leavitt

As told us in the episode, Henrietta Leavitt's story is one "of persistence against the odds." Henrietta was a "computer" at Harvard and tabulated data from photographic plates. Through her curiosity and hard work, she created the Leavitt Law, which allows astronomers to measure distances to other galaxies and more!

Want to learn more about Henrietta and her law? Check out this video:

Here's what one of Leavitt's photographic plates would have looked like. Grown-ups, click here to learn more about this astronomical art!

Scientist with gloves holding a photographic plate to the light. The plate is a somewhat transparent and dark. When held to the light, images of the sky appear.

Scientist with gloves holding a photographic plate to the light. The plate is a somewhat transparent and dark. When held to the light, images of the sky appear.
Photo Credit: Harvard-Smithsonian Center for Astrophysics

Here's Henrietta at her desk in Harvard College Observatory. Click here to see Henrietta's work being used in a 1912 Harvard College Observatory Circular. Edward Pickering used Henrietta's data but did not credit her. Not cool, Pickering!

Look Up! Book cover. Pictured is Henrietta looking to the stars.

For more stories of Henrietta, check out Look Up! by Robert Burleigh and illustrated by Raúl Colón. This children's book tells Henrietta's inspiring story, with pictures!

Finally, here's a visualization of the size of space. It's daunting to say the least!

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