from Hubble’s legacy by Mario Livio

In-flight servicing has prolonged the space telescope’s life, paving the way for future missions.
1990
The Hubble Space Telescope is launched on the space shuttle Discovery on 24 April. Distortions in the mirror are discovered on 25 June.
1993
In the first servicing mission, astronauts fix the optics and install a new camera.
1996
The first Hubble Deep Field image is released, showing far-flung galaxies.
1997, 1999 & 2002
Servicing missions add a spectrograph and an infrared camera, fix worn gyroscopes that keep the telescope pointing correctly, and replace a camera and solar panels.
2004, 2007
Power supplies fail on the spectrograph (2004) and on a camera (2007).
2008
Hubble shows exoplanet Fomalhaut b and completes its hundred-thousandth orbit of Earth.
2009
Astronauts carry out extensive repairs, and install a new camera and spectrograph.
2011
Hubble makes its millionth observation (of an exoplanet) and the ten-thousandth scientific paper using its data is published (concerning supernovae).
2018
The James Webb Space Telescope will open up infrared views of the Universe.
~ 2024
WFIRST/AFTA will enable large surveys in the infrared from space.
~ 2030
Proposed launch of a new major observatory to image and characterize exoplanets.