Free Online Lectures

Each event features a noted scientist who discusses a different cosmic topic. These lectures will be presented with a livestream to YouTube, and questions can be asked in the YouTube chat. The recordings will also be posted on our YouTube channel and accessible from this page.

Lectures are typically held at 8 PM EDT (UTC -4) during Daylight Time and 8 PM EST (UTC -5) during Standard Time, unless otherwise noted.

Mosaic of Hubble imagery

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Past Lectures

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  1. Black Holes: How Do We See That Which Gives Off No Light?

    November 1, 2022 Lectures

    Speaker: Stephanie La Massa (Space Telescope Science Institute) Black holes are the most enigmatic objects in the universe, objects so dense that not even light can escape from them. However, observational...

  2. The Universe of Dante Alighieri

    October 4, 2022 Lectures

    Speaker: Sperello di Serego Alighieri “The Divine Comedy” by Dante Alighieri is the story of a journey through the universe—a sort of ante litteram science fiction book, written...

  3. First Light: Hunting for Galaxies at the Dawn of Cosmic Time

    September 6, 2022 Lectures

    Speaker: Guido Roberts-Borsani (UCLA) The emergence of the first galaxies some 13.5 billion years ago had a profound effect on the state of the universe. It marks the end of the so-called Dark Ages...

  4. Webb's First Look: Images and Spectra from NASA's Newest Great Observatory

    August 2, 2022 Lectures

    Speaker: Alexandra Lockwood (Space Telescope Science Institute) The Webb Space Telescope has recently showcased its spectacular first images and is now ready to do incredible science! It has been...

  5. How Yavin IV and Orbital Mechanics Destroyed the Death Star

    July 5, 2022 Lectures

    Speaker: Mia Bovill (Texas Christian University) At the end of “Star Wars: Episode IV,” the Death Star orbits the moon Yavin IV while seeking to target the rebel base on its surface....

  6. Understanding the Formation and Evolution of Galaxies

    June 7, 2022 Lectures

    Speaker: Cameron Hummels (Caltech) Galaxies—like our own Milky Way—are among the basic building blocks of our universe. Discovered only one hundred years ago, galaxies are complex systems...

  7. Eta Carinae and the Homunculus Nebula in 3D

    May 3, 2022 Lectures

    Speaker: Frank Summers (Space Telescope Science Institute) Eta Carinae is the closest, best known, and most studied of the stars known as "supernova impostors". After surviving a supernova-like...

  8. Neutrino Astronomy: A New Window into the Extreme Universe

    April 5, 2022 Lectures

    Speaker: Marcos Santander (University of Alabama) Located under a mile of glacial ice near the South Pole is IceCube, the largest neutrino telescope in the world. IceCube detects high-energy neutrinos,...

  9. Hubble from Space and Integral-field Spectroscopy from the Ground: Seeing Both the Forests and the Trees

    March 1, 2022 Lectures

    Speaker: Marc Sarzi (Armagh Observatory & Planetarium) Integral-field spectroscopy (IFS) has driven tremendous progress in many areas of astronomy in the past two decades. Using a combination...

  10. To Catch A Dancing Star: The Story of "Extreme Precision" Spectroscopy

    February 1, 2022 Lectures

    Speaker: Arpita Roy (Space Telescope Science Institute) It has been three decades since astronomers first discovered planets outside our solar system. This profound scientific moment established the field...

  11. The Vibrant Life in Cities of Galaxies

    January 4, 2022 Lectures

    Speaker: Mireia Montes (Space Telescope Science Institute) A galaxy cluster is a collection of hundreds to thousands of galaxies—a "city" of galaxies. Similar to our human...

  12. The Webb Space Telescope: Launching a Legacy

    December 7, 2021 Lectures

    Speaker: Alexandra Lockwood (Space Telescope Science Institute) Originally envisioned in the late-1980s, NASA's next flagship observatory, the Webb Space Telescope, is now reaching fruition....

  13. 4000 Years of Women in Science

    November 2, 2021 Lectures

    Speaker: Dr. Sethanne Howard (Washington Academy of Sciences) For more than 4,000 years of written knowledge, women have participated in the great human adventure of science. Female creativity and...

  14. How Dark Is Space?

    October 5, 2021 Lectures

    Speaker: Dr. Tod Lauer (NSF's NOIRLab) Looking at the sky on a clear moonless night, one sees stars against black space. Powerful telescopes reveal faint stars and galaxies strewn between the...

  15. Astronomy vs Astrology: What's the Difference, Really?

    September 7, 2021 Lectures

    Speaker: Nicole Arulanantham (Space Telescope Science Institute) It is inevitable in every astronomer's career that sometime, someplace, someone will refer to them as an astrologer. Although the scientist...