William Shatner and Neil deGrasse Tyson regaled an enthusiastic crowd with stories of everything from our understanding quantum physics to Shatner‘s space flight to the meaning of the universe on Wednesday night during a conversation dubbed “The Universe Is Absurd!” at the Saban Theatre in Beverly Hills.

The event was actually the second of a two-night event wherein the close friends ribbed each other and shared personal anecdotes of their adventures together, including their 2024 trip to Antarctica, where they first met. The audience may have even learned a few things about astrophysics along the way. (“The electron is so small, we do not know how small it is,” Tyson shared. “Every measurement of the electron is smaller than our attempts to measure it. As far as we’re concerned, it’s infinitesimally small.”)

The topic of Shatner’s age (95 years) came up quite often. At one point, he mentioned his forthcoming heavy metal album (yes, you read that right), out in October. (“Why does everyone approach me with a smile when they hear ‘heavy metal album’?” Shatner deadpanned.)

Later, Tyson turned the talk to back to quantum physics, noting that Shatner was born in 1931, which earned him some applause, at which the actor bristled, quipping: “I don’t like being applauded for my age. Applaud me for my heavy metal album.” Tyson went on to note that the neutron was discovered by James Chadwick the year after Shatner was born. The astrophysicist then went on to explain quantum physics to the crowd, some of whom were familiar with the topic (THR sat next to a woman who works as an engineer at Blue Origin) and others who were not. In the 1920s, “we learned that the universe is not continually divisible. You reach a point, you have a certain amount of energy, then you have less energy and less and less and less. There’s a point where there’s a unit of energy and you cannot have less than that. That is a quantum of energy.”