24-APR-1990 :- The Hubble Space Telescope is launched from the Space Shuttle Discovery.

Hubble Space Telescope (HST)
is a space telescope that was launched into low Earth orbit in 1990, and remains in operation. With a 2.4-meter (7.9 ft) mirror, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared spectra. The telescope is named after the astronomer Edwin Hubble.

The Hubble, which has so far travelled more than 3 billion miles, has made more than 1.2 million observations since 1990 by completing an orbit around the Earth every 97 minutes at a speed of about 8 km per second.

A household name today, it was an instrument that “much of the astronomical community didn’t want!” Worse, it almost turned out to be a dud soon after the launch.

The Universe is gloriously transparent to visible light over journeys lasting billions of years. However, in the last few microseconds before light arrives at telescope mirrors on Earth it must travel through our turbulent atmosphere and the fine cosmic details become blurred. It is this same atmospheric turbulence that makes the stars appear to twinkle on a dark night.

Putting a telescope in space is one way of evading this problem. As well as collecting visible light from its orbit high above the atmosphere, the Hubble Space Telescope also observes the infrared and ultraviolet wavelengths that are completely filtered out by the atmosphere.

The Hubble Space Telescope, a joint ESA and NASA project, has made some of the most dramatic discoveries in the history of astronomy. From its vantage point 600 km above the Earth, Hubble can detect light with 'eyes' 5 times sharper than the best ground-based telescopes and looks deep into space where some of the most profound mysteries are still buried in the mists of time.