APERTURE
A FIELD GUIDE TO HUBBLE & SPACE TELESCOPES
Ten chapters on the 2.4-metre mirror that had to be launched with a flaw, fixed by hand in orbit, and rebuilt into the sharpest eye humanity has ever pointed at the universe — and on what came after it. Scroll to begin the mission.
BEGIN — CHAPTER 01 →A 100-km blanket of blur
Earth's atmosphere is wonderful to breathe and terrible to look through. Turbulent air blurs starlight — the same effect that makes stars twinkle — and the atmosphere blocks most ultraviolet and infrared light outright before it ever reaches a ground-based mirror.
Move the same distant galaxy from a ground-based view to orbit and see the difference.
Twenty years from proposal to orbit
First proposed in the 1940s and seriously funded from 1977, Hubble launched aboard Space Shuttle Discovery on April 24, 1990 — and within weeks, engineers found a problem no one expected.
A mirror ground wrong by 2 microns
A bus-sized telescope, taken apart
Hubble is built like no ground telescope needs to be — serviceable, modular, and designed for astronauts in bulky gloves to swap parts in orbit. Select a component.
Rebuilt in orbit, five times
Between 1993 and 2009, five Space Shuttle missions visited Hubble to repair, upgrade, and extend it — something no other space telescope has ever had done to it. Scrub through the missions.
Rewriting the textbook, repeatedly
More than visible light
Hubble sees ultraviolet, visible, and near-infrared light — a wider slice of the spectrum than the human eye, but only part of what's out there. Different observatories are built for different bands.
Not a replacement — a different eye
Webb didn't retire Hubble; the two observe different light from different vantage points, and both are still running today.
Down to one gyroscope, still working
Figures below are current to mid-2026. With Space Shuttle retired, no further servicing missions are currently planned — Hubble now runs on whatever hardware is already on board.
One observatory, a whole fleet after it
Hubble proved a space telescope was worth the cost and the risk. Everything after it has been an argument about what to build next.