Today marks the 25th anniversary of the Hubble Space Telescope, launched 24 April 1990. Operating in the optical, ultraviolet and near-infrared wavebands, HST’s low-earth orbit gives it unprecedented image quality outside of the “blurring” of the Earth’s turbulent atmosphere. HST has revolutionised our view of the universe and brought us some of the highest resolution and most spectacular images from our solar system, our galaxy and the distant universe. The real success of HST has been its amazing public reach, bringing astronomy to people across the globe.
HST got off to a rather shaky start, however. There were problems with the shape of Hubble’s 2.4-m primary lens and the first images sent back to earth with disappointingly blurry! The first HST serving mission in December 1993 installed lenses to correct the optical aberration.
A total of 5 servicing missions between 1993 and 2009 were carried out, replacing failed equipment and installing new instruments. With the end of the space shuttle program in 2011, further HST servicing missions are no longer possible, but NASA will continue to maintain HST for as long a they can.
Some of HST’s key science outcomes have included studying weather patterns on other planets in our Solar System, studying the atmospheres of exoplanets, peering into star forming regions, studying interacting and merging galaxies, measuring the expansion rate of the universe, and views of the most distance universe 13.3 billion years ago.
Each year HST releases a special birthday image. For its 25th anniversary, this year’s image is of the stellar cluster and star forming region Westerlund 2 in the Gum 19 nebula. The central star cluster contains about 3000 stars. The image combines visible light from an image taken by the Advanced Camera for Surveys with near-infrared images from the Wide Field Camera 3. The red colours represent regions dominated by hydrogen, while the bluish-green hues are predominantly oxygen. (You can also watch a 3D fly through here).
Three great articles were published in The Conversation this week which we encourage you to read:
- Why the Hubble Space Telescope has been such a stellar success, Micheal Brown, The Conversation, 22 April 2015
- Hubble Space Telescope’s chief scientist on what it took to get the project off the ground, Bob O’Dell, The Conversation, 22 April 2015
- Hubble in pictures: astronomers’ top picks, Tanya Hill, The Conversation, 22 April 2015
For more information about HST and its 25 year history, see:
- Celebrating 25 years of the NASA/ESA Hubble Space Telescope, HST website
- Hubble 25, HST/ESA’s 25 year history of HST