By Neil deGrasse Tyson
A rapid tour of the cosmos
Subject
Themes
Nearly 14 billion years ago, the entire observable universe occupied a volume smaller than the period at the end of a sentence. The Big Bang was not an explosion into space but the expansion of space itself, beginning from conditions so extreme that current physics cannot fully describe them. In the first fractions of a second, the four fundamental forces separated from a single unified force. For every billion particles of antimatter produced, a billion and one particles of matter existed. When the two annihilated each other, that surplus of one particle in a billion became everything: every star, planet, galaxy, and human being.
Nearly 14 billion years ago, the entire observable universe occupied a volume smaller than the period at the end of a sentence. The Big Bang was not an explosion into space but the expansion of space itself, beginning from conditions so extreme that current physics cannot fully describe them. In the…
"Astrophysics for People in a Hurry" appeared in 2017 and became one of the fastest-selling science books in recent memory, reflecting a cultural moment in which public appetite for rigorous scientific knowledge about the cosmos had grown well beyond the reach of specialist publishing. The book…
The entire observable universe, all of its matter, energy, and space, once occupied a volume smaller than the period at the end of a sentence. This was not matter compressed inside a pre-existing void. Space itself did not exist. Then, nearly 14 billion years ago, everything expanded from that state…
Before Isaac Newton, the universe had two sets of rules. Heaven operated under divine governance, subject to laws that mortals could not fully comprehend. Earth operated under ordinary physical causation. Newton demolished this division by showing that the gravity pulling an apple from a tree is the…
Everything that can be seen, touched, measured, or catalogued in astronomy, every star, planet, gas cloud, and galaxy, makes up just 5 percent of the total mass-energy of the universe. The remaining 95 percent consists of two substances so unlike ordinary matter that they have no satisfactory…
The hydrogen in a glass of water was forged in the first two minutes after the Big Bang. The carbon in every living cell was manufactured inside a star that no longer exists. The iron in blood was produced in the core of a massive star and scattered across space when that star exploded as a…
When a psychology professor wrote to a planetarium saying that a space show had induced the most profound feelings of insignificance he had ever experienced, and that he planned to survey visitors for signs of depression, the reaction from the presenter was bafflement. The same show that left the…
Nearly fourteen billion years ago, all the space, matter, and energy of the known universe occupied a volume smaller than the period at the end of a sentence. From that unimaginably dense starting point, the universe could only expand. The big bang was not an explosion into existing space but the…
Light has a history. The photons streaming through space today carry imprints of the universe's earliest moments, and reading those imprints has transformed cosmology into a precision science. In the 1940s, physicists Ralph Alpher and Robert Herman predicted that the Big Bang should have left a…
The universe is mostly made of things that cannot be seen. In 1937, Swiss-American astrophysicist Fritz Zwicky measured the orbital speeds of galaxies within the Coma cluster, a dense collection of roughly a thousand galaxies about 300 million light-years from Earth. The numbers made no sense. The…
Every atom in the human body was forged inside a star. Only three elements emerged from the Big Bang: hydrogen, helium, and lithium. Everything else on the periodic table was manufactured in the nuclear furnaces of stars and scattered across space when those stars exploded as supernovae. The…
The universe communicates across a far wider range of frequencies than human eyes can detect. In 1800, William Herschel spread sunlight through a prism and placed thermometers across the resulting spectrum to measure the temperature of each colour. As a careful experimentalist, he also placed a…
From just beyond Neptune's orbit, as Voyager 1 demonstrated in 1990, Earth is a pale blue dot, barely distinguishable from the blackness of space. That image invites a practical question: what could a technologically capable alien civilisation actually detect about Earth from a great…
By Neil deGrasse Tyson
Subject
Themes
Nearly 14 billion years ago, the entire observable universe occupied a volume smaller than the period at the end of a sentence. The Big Bang was not an explosion into space but the expansion of space itself, beginning from conditions so extreme that current physics cannot fully describe them. In the first fractions of a second, the four fundamental forces separated from a single unified force. For every billion particles of antimatter produced, a billion and one particles of matter existed. When the two annihilated each other, that surplus of one particle in a billion became everything: every star, planet, galaxy, and human being.