At the beginning of his presentation Thursday night at The Granada Theatre, astrophysicist and “rock star scientist” Neil deGrasse Tyson said, “I have the whole universe to deliver” so he would have to go beyond a standard 45-minute talk. The crowd roared its approval, and was subsequently treated to more than two fascinating hours of Tyson’s view of the universe, plus more than an hour of Q&A.
Along the same lines, I can’t cover his whole talk in 1,000 words, but I’ll at least try to hit some of the highlights.
Tyson, who is the Frederick P. Rose Director of the Hayden Planetarium at the American Museum of Natural History in New York City, and is currently working on a 21st-century reboot of the popular television series COSMOS, was making his first visit to Santa Barbara, thanks to UC Santa Barbara’s Arts & Lectures Series. He titled his talk “Cosmic Discovery (And What It Takes to Enable It).”
He started by talking about Mars, including the story of how Percival Lowell erroneously believed that he saw canals on the planet’s surface. (Tyson said it has been suggested that these and similar canals that he “saw” on Venus were actually projections of the blood vessels in Lowell’s eyeball as he looked into his telescope.) But, canals or not, he noted that there is in fact evidence that water is present beneath the Martian surface as permafrost, which could be important for both the possibility of life on Mars, and also because water can be made into rocket fuel for a return trip by breaking it into its constituent parts hydrogen and oxygen.
Tyson next discussed Saturn, showing a stunning photo taken by the Cassini spacecraft of Saturn eclipsing the sun. He pointed out that Earth appears in this photo as a tiny dot just six pixels in size. He also told of the methane lakes on Titan, one of Saturn’s moons.
The conversation then turned to Pluto, whose demotion from “planet” to “dwarf planet” is largely due to Tyson and a renovation of the Hayden Planetarium. He started this part of his presentation with a slide saying, “It’s STILL not a planet (Get over it!)”, noting that Pluto has only one-fifth the mass of our moon, and more than half of it is ice.
The controversy about Pluto took off when The New York Times published an article in 2001 called, “Pluto’s Not a Planet? Only in New York,” which extensively quoted Tyson. At the talk, he joked, “Then came the hate mail from third-graders.” He showed one letter from a fourth-grade girl, which amusingly ended with the sentence, “Please write back, but not in cursive because I can’t read in cursive.” He also showed a recent email apology from someone who, as a kid, had sent a letter that called him a “big poopoo-head” when the controversy erupted.
Next up was a discussion of “Killer Asteroids,” including the recent Chelyabinsk meteor that was only about the size of The Granada stage but was moving at 40,000 mph. This heated up and exploded 20 miles above the Earth with 25 times the energy of the Hiroshima atomic bomb. Tyson said it was fortunate that it exploded so high, or it would have caused much more damage. But still, 1,000 people were injured, mostly from broken glass when people ran to the window to see what had happened, not appreciating that the shock wave, which moved at the speed of sound that is much slower than the speed of light, hadn’t arrived yet.
Tyson said that there is another meteor on the way, called Apophis after the Egyptian god of darkness and evil. This will come close to the Earth on April 13, 2029 (a Friday, of course), and seven years later, due to its elliptical orbit, will come close again, with a one in a million chance of hitting the Earth. If it hits, it’s expected to be in the Pacific Ocean 500 kilometers west of Santa Monica, and will lead to a series of tsunamis that will destroy a swath about a quarter-mile wide along the U.S. coastline.
Tyson finished with some intriguing thoughts, including the possibility (called panspermia) that life on Earth may have “migrated” from Mars when a meteor hit the Martian surface and ejected a bacteria-rich piece of Mars that landed on the Earth. Crazy as this sounds, it would explain the “hardy bacteria” that are resistant to extreme conditions found in space but not on Earth — only those bacteria that survived the trip would be able to seed Earth’s tree of life.
He also talked a bit about the recently discovered Higgs boson (aka, the “God Particle”), the mystery of dark energy and dark matter that make up 96 percent of the universe, and how the United States is on an unfortunate path of losing its scientific supremacy to other countries.
During the Q&A period, Tyson was asked what his most memorable scientific experience was. He mentioned two: first, witnessing a total solar eclipse when he was on a boat in the Atlantic Ocean off the west coast of Africa, and second, his first visit to the Mount Wilson Observatory, which was used by Edwin Hubble to show that the universe is expanding.
Tyson was also asked for advice for science majors. He said to take the hardest possible classes that are available, which will expand the student’s mind and distinguish him or her from the masses who take “easy” classes just to get good grades.
Not only was Tyson educational and inspiring, he was also funny. For example, he claimed that astrophysicists are simple people, in the sense that they come up with very straightforward names for sophisticated phenomena and ideas. When they discovered that there are spots on the sun, they called them “sunspots.” When a certain persistent structure was found on Jupiter, they called it “Jupiter’s Red Spot.” The beginning of the universe is called, quite simply, the “Big Bang.” He contrasted this with biology, which calls the most important molecule in the human body “deoxyribonucleic acid,” which is so complicated that they have to abbreviate it as DNA.
Tyson closed his presentation by stating that the relative abundances of elements in life on Earth are the same as the relative abundances of elements in the universe. He summarized this by saying that, “We are stardust. The universe is in us.”
And thanks to Tyson’s efforts, many of us now have a greater appreciation for the amazing things that our universe, in and out of us, encompasses.
— Jeff Moehlis is a Noozhawk contributing writer and a professor of mechanical engineering at UCSB. Upcoming show recommendations, advice from musicians, interviews and more are available on his web site, music-illuminati.com. The opinions expressed are his own.