telescope

William Herschel discovered Uranus in 1781, found infrared radiation in 1800, built the world's largest telescope, and only became an astronomer after a career as an oboist.

Mirrors don't actually flip left and right — they flip front to back. The physics of reflection, from bronze polish to the 39-meter ELT telescope.

In January 1610, Galileo saw four stars near Jupiter that moved. Within a week he understood the solar system would never be the same.

Hubble launched with a flawed mirror and came back from the brink to become humanity's greatest eye on the cosmos.

Since 1999, Chandra has mapped X-rays from black holes, neutron stars, and galaxy clusters, transforming understanding of the universe's most violent phenomena.

NASA's Fermi telescope mapped the gamma-ray universe, revealing pulsars, black holes, and mysterious transient events at highest photon energies.

December 1995: Hubble stared at one blank patch of sky for about 10 days and found roughly 3,000 galaxies, changing how astronomers count the universe.

July 2022: JWST's first images revealed galaxies 13.6 billion light-years distant, formed just 100 million years after the Big Bang, reshaping cosmology.

TESS discovered 5,600+ exoplanets using transit photometry, revolutionizing our census of worlds and identifying prime targets for atmospheric study.

Radio telescopes collect faint radio waves from pulsars, galaxies, hydrogen gas, and black holes. Because radio waves are long, sharp images need either a giant dish like China's 500-meter FAST or an array of dishes combined by interferometry, like the VLA.

JWST sits 1.5 million kilometers from Earth, sees light from galaxies 280 million years after the Big Bang, and is actively rewriting cosmology. Here's how the most ambitious telescope ever built actually works, and what it has found through 2026.