Hubble Space Telescope
An observatory above the atmosphere, and a satellite you can follow around Earth. Hubble connects the science of distant galaxies with the very practical question of where a spacecraft is right now.
- Launch date
- April 24, 1990
- International designator
- 1990-037B
- Mission
- Astronomy
- Primary mirror
- 2.4 metres
- Launch mission
- Discovery · STS-31
- Catalogue name
- HST
Why put a telescope in orbit?
Earth's atmosphere affects the light reaching a telescope on the ground. Placing an observatory in space gives astronomers another way to study the universe. Hubble was designed around a 2.4-metre primary mirror and observations in visible and ultraviolet light.
The telescope launched aboard Space Shuttle Discovery on April 24, 1990. Its journey was the result of decades of planning for an observatory that astronauts could maintain in orbit.
A telescope that astronauts could improve
Hubble's first images revealed an optical problem in its primary mirror. In December 1993, a servicing crew installed corrective optics and a replacement camera, improving the telescope's image quality.
Five shuttle servicing missions repaired and upgraded Hubble. The final visit in 2009 installed Wide Field Camera 3 and the Cosmic Origins Spectrograph, among other work. That history is an important part of understanding the observatory: it did not remain the same instrument that first launched.
What the tracker shows
The moving point in the tracker represents Hubble itself, not the distant object its telescope is observing. Open its Info and TLE tabs to see the selected spacecraft and the age of its orbital elements. A pass above your horizon is not a promise that Hubble will be visible to the naked eye.
Choose Track live to open this exact NORAD ID on the globe. From there you can open Info, inspect TLE data, explore the charts or calculate upcoming passes. Sign in and tap the star to keep the satellite in your existing favorites.
Open Hubble in the tracker