Konstantin Batygin — Planetary astrophysicist at Caltech and a leading proponent of the Planet Nine hypothesis. With collaborator Mike Brown he argued that clustered orbits of distant Kuiper Belt objects point to an unseen distant planet about five Earth masses.
The gist
Batygin walks through the architecture of our solar system, from the inner rocky planets to Jupiter and Saturn out to the Kuiper Belt and the vast, nearly spherical Oort Cloud that stretches halfway to the nearest star. He lays out the evidence for Planet Nine: a hypothesized five-Earth-mass body on a 10,000-year orbit, inferred from the way distant icy objects cluster and tilt rather than from any direct image. The conversation explores how planets form, why Earth and the solar system are roughly a one-percent outcome, the chaos of three-body dynamics, and why full simulations of the solar system would be cool but scientifically useless. It ranges into primordial black holes, the interstellar visitor 'Oumuamua, alien junk, the value of useless knowledge, and Batygin's life as a Russian-born immigrant, musician, and scientist.
Big reveals
- Batygin says the false-alarm probability of the Kuiper Belt clustering behind Planet Nine is about 0.4 percent under their preferred statistical analysis.
- He argues the solar system likely once had a compact system of inner planets that Jupiter's primordial migration destroyed before Earth formed.
- He states that the three-body problem is chaotic, so simulating the whole solar system from scratch would be a futile pursuit for prediction.
- Batygin recounts deriving the Schrodinger equation from gravitating concentric rings, noting the equation is a wave equation with nothing inherently quantum about it.
- He entertains that Planet Nine could be a five-Earth-mass primordial black hole rather than a planet, since gravity alone cannot distinguish them.
- He favors the theory that 'Oumuamua is a hydrogen-ice iceberg from a giant molecular cloud, explaining its shape and acceleration.
- Batygin says he would not want to die on Mars and pushes back on Mars as a safe-haven, calling living there worse than camping in the Mojave.
- He notes his academic advisor's advisor's advisor lacked a PhD and Faraday derived his law from intuition without knowing algebra.
Things worth remembering
- Pluto's surface area is almost exactly equal to the surface area of Russia, yet it is roughly 500 times less massive than Earth.
- A distant Kuiper Belt object central to the Planet Nine story is nicknamed Biden (VP113) because Joe Biden was vice president when it was found.
- The Oort Cloud is so vast it ends roughly halfway between the Sun and the next star, defined by how far solar gravity reaches.
- The outer solar system is essentially collisionless; Batygin guesses there have been zero collisions in the Oort Cloud over the solar system's age.
- Jupiter-and-Saturn-like planet pairs are found around only about 10 percent of Sun-like stars, making our configuration relatively rare.
- Aluminum-26 in meteorites shows the solar system formed in a cluster of thousands of stars, some of which went supernova.
- New Horizons revealed Pluto has flowing glaciers made of carbon-monoxide ice, since water ice behaves like metal at 40 Kelvin.
- Batygin praises the book on the usefulness of useless knowledge by the founder of the Institute for Advanced Study.
- He notes a few percent of the entire electrical grid went to mining Bitcoin, raising the question of what computation looks like from space.
- Batygin describes standing in line about six hours for Moscow's first McDonald's and marveling at the sesame seeds on the bun.
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“one of my favorite beetle songs is it's uh you know in my life right that's it's it's hard to imagine how whatever 24 year old wrote that” — Konstantin Batygin 02:11:55Find it on Amazon
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“you can sort of look at the entire dark side of the moon album and getting pretty close up there to the pinnacle of what can be created” — Konstantin Batygin 02:11:55Find it on Amazon
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Pink Floyd
“you have that with the wall of just uh transporting you into another place songs don't not many songs could do that” — Lex Fridman 02:12:27Find it on Amazon
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“i would say output johnny cash's cover of hurt as one of the greatest songs of all time” — Lex Fridman 02:14:31Find it on Amazon