Take Me to Your Leader

Neil deGrasse Tyson, astrophysicist and director of New York City's Hayden Planetarium, opens with a personal confession: Ever since childhood, he has wanted to be abducted by aliens. His fascination began with a childhood visit to the Hayden Planetarium and deepened during PhD research in Chile, where he spent years conducting solitary telescope observations. He frames the book as a scientifically grounded guide to a hypothetical first encounter with extraterrestrial life, posing a central question: If an alien demands "Take me to your leader," what should humanity do? Rather than presenting political, cultural, or religious figures, he suggests we might be better served by presenting those with scientific expertise. The book, he writes, is a manual of etiquette and insight for a close encounter, grounded in the scientific skepticism that establishes objective truths.

In Chapter 1, "Alien to Us," Tyson surveys how humans have imagined aliens and argues that those conceptions are shaped far more by human biology and cultural bias than by scientific reasoning. He notes that all Earth life shares a common origin: Humans share 99 percent of their DNA with chimpanzees and 25 percent with bananas. A space alien with no genes in common with Earth life should therefore look far more different from us than we look from a banana, yet Hollywood overwhelmingly depicts humanoid aliens. He points to the Burgess Shale fossil fields in British Columbia, Canada, which preserve soft-bodied creatures from 500 million years ago with wildly varied body plans, as a real-world catalog of biological creativity that surpasses most film designs.

Tyson critiques the Ancient Aliens television franchise and Erich von Däniken's 1968 book Chariots of the Gods for attributing ancient art, the Nazca geoglyphs (giant ground drawings etched into the Peruvian desert), and the Egyptian pyramids to extraterrestrial intervention. He argues this denies ancient peoples their intelligence and highlights the racist undertone of denying African civilizations their achievements. He traces the evil-alien genre to H. G. Wells's serialized novel The War of the Worlds (1895–1897) and links many alien-encounter accounts to the scientific phenomenon of sleep paralysis. He challenges biological assumptions about alien life, discussing silicon as an alternative to carbon-based biochemistry but arguing carbon is far more abundant and versatile. The chapter closes with the story of Giordano Bruno, the sixteenth-century Italian monk-philosopher burned at the stake by the Holy Roman Inquisition, the Catholic Church's tribunal for prosecuting heresy, for arguing that stars might harbor planets with life. Tyson notes that by 2009, the Vatican's own Pontifical Academy of Sciences convened a conference on extraterrestrial life.

Chapter 2, "Alien to Them," inverts the perspective. Tyson imagines what humans and Earth would look like to visiting aliens, arguing that our egocentrism distorts our self-assessment. He draws on Voltaire's 1752 novella Micromégas, in which a 23-mile-tall alien from the star Sirius visits Earth and is astonished that microscopic humans believe the universe was made for them. He presents astronomer Frank Drake's 1973 thought experiment imagining life on neutron stars, the ultra-dense remnants of massive stars, where beings made of subatomic particles might live for fractions of a second and consider our existence too bizarre to support life. He imagines aliens landing in Los Angeles and concluding that Earth's dominant life-form is the automobile. He describes Earth's expanding "radio bubble," noting that the earliest broadcast signals reaching other star systems include Hitler's rallies and early American television, offering aliens a misleading first impression. He warns that Earth's growing shell of orbital debris would give visitors further reason to question humanity's wisdom, and closes by arguing that evidence of human irrationality would lead aliens to report no sign of intelligent life on Earth.

Chapter 3, "Alien Intelligence," examines what intelligence means relative to alien life. Since humans and chimpanzees differ by roughly 2 percent of their DNA yet humans consider themselves vastly superior, Tyson asks what a species 2 percent beyond humans would look like. Their toddlers, he argues, would surpass the greatest human minds. He speculates that superintelligent aliens may have created Earth as an aquarium for their amusement, drawing an analogy to ant farms. He proposes mathematics as the ideal first point of contact, describing nineteenth-century mathematician Carl Friedrich Gauss's proposal to build a giant Pythagorean triangle visible from space, and identifies Pi as a universally recognizable constant. He critiques alien intelligence in popular culture, pointing to the alleged 1947 Roswell aliens who supposedly traversed interstellar space but crash-landed, the obtuse coordinate system in Close Encounters of the Third Kind (1977), and V-ger from Star Trek: The Motion Picture (1979), which acquired all knowledge of the universe yet did not know its own name.

Chapter 4, "Alien Science & Technology," argues that the universal laws of physics constrain all technology. Tyson identifies three fundamental constants, the speed of light, Planck's constant, and the gravitational constant, as potential common ground with alien scientists, since physicist Max Planck showed in 1899 that combining these constants yields units of measurement independent of any species or planet. He debunks popular UFO tropes: Smooth rotating saucers violate conservation of angular momentum, the principle that a spinning body requires a balancing counter-rotation or exhaust, and rapid acceleration would destroy biological tissue. He uses NASCAR driver Dale Earnhardt's fatal crash at the 2001 Daytona 500, caused by approximately 60 Gs of deceleration, to illustrate how abrupt speed changes break molecular bonds. He presents Fermi's Paradox, named for physicist Enrico Fermi, which asks why, given the Milky Way's age and size, no alien colonists are evident on Earth. His preferred answer is the Cosmic Quarantine Hypothesis, developed by his museum colleague Steven Soter, which proposes that colonization-driven aliens inevitably fight among themselves for diminishing territory, causing their expansion to collapse, just as Earth's colonial powers warred over contested lands.

Chapter 5, "Alien Powers," evaluates commonly attributed alien abilities against the laws of physics. Many supposed superpowers, from speed to regeneration, already exist in Earth's animal kingdom. Tyson analyzes telepathy as neurochemical and electromagnetic impulses detectable, in principle, by scientific instruments, and he explains that higher-dimensional aliens could see inside any three-dimensional enclosure, including human bodies, simply by existing in four or more spatial dimensions. He evaluates time manipulation through Albert Einstein's theory of relativity, which permits the flow of time to be influenced by gravitational fields, and concludes that while time cannot be fully stopped, it can be made to pass arbitrarily slowly.

Chapter 6, "Alien Evidence," applies scientific standards to UFO claims. Tyson frames the chapter around what he calls "Aliens of our ignorance," the tendency to attribute unexplained phenomena to extraterrestrial visitors, just as earlier generations invoked divine intervention for gaps in knowledge. He presents data showing that reported UFO shapes have shifted over time, with orbs now far exceeding the iconic saucer, and notes that sightings occur overwhelmingly in English-speaking countries. He catalogues commonly misidentified phenomena, including the planet Venus, noctilucent clouds (high-altitude clouds that glow after sunset), and orographic clouds (clouds formed by air rising over mountains). He discusses pareidolia, the human tendency to perceive familiar forms in random patterns, as an explanation for the "face" on Mars. He chronicles US government engagement with unidentified aerial phenomena from the 1947 Roswell incident through the 2023–2025 congressional hearings, in which whistleblowers testified about recovered alien spacecraft and "nonhuman biologics," but no physical evidence was presented. He notes that the world's 7 billion smartphones have produced no clear alien images and that abduction reports have plummeted in the smartphone era.

Chapter 7, "Alien to Me," turns personal. Tyson recounts his congressional testimony supporting funding for the search for extraterrestrial life and describes Drake's 1960 Project Ozma, the first systematic radio search for alien signals. He presents the Drake Equation's logic for estimating communicative civilizations in the Milky Way, which he and Princeton colleagues calculate at roughly 100, spaced about 5,000 light-years apart. He recounts his 2023 public calls for physical alien evidence and his email exchange with researchers who displayed alleged alien mummies before the Mexican Congress, directing them to submit findings for peer review. A Peruvian forensic archaeologist later reported the figures were assembled from animal and human bones with synthetic glue. He cites Pew Research data showing that nonreligious people are significantly more likely than religious people to believe in intelligent extraterrestrial life, suggesting that the urge to believe persists even without traditional religion. He asserts that until someone presents an actual alien for scientific examination, alien visitation will remain a belief system.

In the Epilogue, Tyson imagines his own abduction. He hopes aliens might impart knowledge that humanity needs to survive its own destructive tendencies, and envisions a future in which humans themselves rocket to inhabited planets, "becoming the Aliens their legends are made of."