Hubble Space Telescope: History and Discoveries
that Changed Our View of the Universe   or   index.html


  What caused this outburst of V838 Mon? For reasons unknown,
  star V838 Mon suddenly became one of the brightest stars in
  the entire Milky Way Galaxy. Then, just a few months later,
  it faded. A stellar flash like this has never been seen
  before -- supernovas and novas expel a tremendous amount of
  matter out into space. Although the V838 Mon flash appeared
  to expel some material into space, what is seen in the above
  eight-frame movie, interpolated for smoothness, is actually
  an outwardly moving light echo of the flash.

History: How Hubble Came About

  The precision-ground mirror was finished in 1981 and the
  assembly of the entire spacecraft was completed in 1985. The
  plan called for a launch on NASA's Space Shuttle in 1986,
  but just months before, the scheduled launch the Challenger
  disaster caused a year long delay of the entire Shuttle
  programme. Hubble was finally launched in 1990 and the
  tension built up as astronomers examined the first images
  through Hubble's eyes.

  As in all good adventures, success does not come easily: it
  did not take long to realise that Hubble's mirror had a
  serious flaw. A focusing defect prevented Hubble from taking
  sharp images -- the mirror edge was too flat by a mere
  fiftieth of the width of a human hair. Over the next months
  scientists and engineers from NASA and ESA worked together
  and came up with a superb corrective optics package that
  would restore Hubble's eyesight completely.

  A crew of astronauts carried out the repairs necessary to
  restore the telescope to its intended level of performance
  during the first Hubble Servicing Mission (SM1) in December
  1993. Although the four subsequent servicing missions were
  at least as demanding in terms of complexity and work load,
  SM1 captured the attention of both astronomers and the
  public at large to a degree that no other Shuttle mission
  since has achieved. Meticulously planned and brilliantly
  executed, the mission succeeded on all counts. It will go
  down in history as one of the highlights of human
  spaceflight. Hubble was back in business.

Servicing Mission 1 (Dec. 1993)

Servicing Mission 2 (Feb. 1997)

Servicing Mission 3A (Dec. 1999)

Servicing Mission 3B (Mar. 2002)

Servicing Mission 4 (May 2009)

Astronomy Picture of the Day Archive