In a lecture all about stars, speaker Michelle Thaller was the brightest in the room.
On Friday, Dec. 6, the retired assistant director for science communications at NASA’s Goddard Space Flight Center hosted the annual Christmas lecture sponsored by Notre Dame’s College of Science.
The event was held at the Century Center in downtown South Bend and was attended by over 200 people, including the dean of the College of Science Santiago Schnell and University provost John McGreevy, along with members of the South Bend community and their children.
Thaller was introduced by Kate Biberdorf, better known as Kate the Chemist, who was speaker at last year’s Christmas lecture and is now the University’s inaugural professor for the public understanding of science. She was quick to comment on the parallels to the original Christmas lecture held at the Royal Institution in London and founded by physicist Michael Faraday.
“Faraday was insistent that the Christmas lecture present science topics to a general audience, including young people, which I see here right now,” Biberdorf said. “We asked them to do it in informative and entertaining ways to spark wonder and curiosity among young minds.”
Thaller presented her lecture as a call to appreciate the sanctity and beauty of the universe, and by extension our own existences, through images captured by the James Webb Space Telescope (JWST).
“For me, astronomy is not about the study of things that are very far away, but it’s a study of us, of where we come from, of what our origins are,” she said.
She explained that the JWST does not operate on the visible light spectrum but instead on infrared light, which is more conducive for discovering objects that do not emit light. She then revealed one of many interactive components of her lecture, a working infrared camera pointed straight at the audience.
“Seeing something that’s warm is one thing that we do with Webb. The most important application of [infrared light] is seeing planets around other stars,” she said.
Two children volunteered for the activity, and Thaller had them demonstrate how the infrared light, which functioned as a heat map, could be manipulated by holding ice or hot water from a tea kettle in their hands.
She described the technical and technological difficulties of the JWST, which were centered on how the satellite would unfold its 20-foot telescopic dish in temperatures below minus 400 degrees Fahrenheit.
“We had to keep going, one thing after another. And if one single out of 300 commands didn’t work, the whole mission was done. There were no backups,” Thaller said.
As Thaller spoke, images of cosmic wonderlands danced across the screen above. Infrared spectacles of Jupiter, the andromeda galaxy and the Pillars of Creation star nursery were among the featured pictures from the JWST.
“Every little dot that you see in [the Pillars of Creation] is a star,” she said. “And to give you an idea how big this is, we said that the nearest star to the Earth is four light years away, and just one pillar of this cloud is actually about … 30 trillion light years.”
Thaller repeatedly harkened back to the festive undertones of the lecture, relating the birth of stars to the birth of Jesus Christ and offering astronomical explanations to Biblical phenomena.
“Some people wonder if the star of Bethlehem, the Christmas star, could have been something like a supernova, a star that appeared briefly bright and then faded away,” she said.
She concluded her lecture discussing how there is still much in the universe for us to discover, from portions of the sky too concentrated with stars or obscured with dust to be seen, to galaxies that are only pinpricks on the most detailed images captured by the JWST.
“You have atoms in you right now that were picked up on the other side of the galaxy,” Thaller said. “Your lifetime, your view of the universe, and everyone around us is a unique way of the universe to know itself. A galaxy made conscious.”
After the talk a Q&A and a trivia session were held for which audience members could win free College of Science t-shirts.
Exiting guests were guided to a room filled with scientific contraptions manned by University graduate students. Kids and parents alike were given the chance to play with the infrared camera, feel the vibrations of strong magnetic fields and observe greenhouse gas effects through the simulations.
