Humanity has been changing the radio sky for a little over a century. Early experimental transmissions, commercial broadcasting, military radar, television, satellite links and communications with spacecraft have all sent some energy beyond Earth.
For six years one of Voyager 1's instruments had counted the same steady drizzle of low-energy particles streaming off the Sun.
The case for looking for life on Europa runs through the bottom of Earth's own ocean.
The cosmic microwave background is supposed to be directionless in the statistical sense.
An object that looks unusually cold and faint on a map of the stars need not be a star at all.
On 28 November 2017, engineers at NASA’s Jet Propulsion Laboratory sent Voyager 1 a command to fire four thrusters that had been silent since November 1980.…
Vera Rubin did not watch individual stars race around distant galaxies in real time.
NASA's Kepler mission did not detect 300 million temperate rocky planets. It observed a narrow field of stars, found the small fraction of planets whose orbits…
The first deep images from the James Webb Space Telescope contained a population that astronomers had not expected to see.
In May 1964, a chart recorder at Bell Telephone Laboratories registered more microwave power from the sky than Arno Penzias and Robert Wilson could explain.
By mid-2026, SpaceX passed 10,000 working Starlink satellites in low Earth orbit — roughly two of every three active satellites now circling the planet — and the company has already filed to fly 100,000 more.
Juno's survival at Jupiter is not just a triumph of navigation. It is a triumph of hiding.
The most distant object humans have ever built runs on computers with less memory than a typical phone photograph.
Most of the matter associated with galaxies is not in the stars, gas, dust, planets, or black holes that telescopes can see.
The New Horizons encounter with Pluto was one of the strangest bargains in modern exploration.
Voyager is not loud anymore. It never really was. The spacecraft carries a transmitter with roughly the power of a household light bulb, and that signal has…
