A tribute to NASA's Swift telescope, which spent 22 years watching stars die, and falls back to Earth this week.
NASA launched Swift in 2004. Its job was to spot the biggest explosions in the universe and point its cameras at them within about two minutes. It was built to last 2 years and kept working for 22. Its orbit has now decayed, and it will burn up in Earth's atmosphere this week.
A gamma-ray burst happens when a giant star collapses into a black hole, or when two dead stars smash together. For a few seconds it outshines entire galaxies. They're so far away that the light is often older than Earth. Swift caught 2,046 of them. Each light sits in the part of the sky the burst came from.
The flash itself is over in seconds. What's left glows for hours or days, then fades. Catching that afterglow was Swift's specialty: it tells scientists how far away the explosion was and what caused it. The orange embers you'll see are those afterglows.
The dot shows roughly where Swift is right now, about 210 km up and dropping. Nobody knows exactly when or where it will come down, so the site shows every forecast side by side.
Every gamma-ray burst NASA's Swift saw, 2004–2026