Hubble Space Telescope
The Hubble Space Telescope (HST) is a joint NASA and ESA observatory launched on April 24, 1990, aboard the Space Shuttle Discovery (STS‑31). Positioned in low Earth orbit at about 547 kilometers altitude, Hubble avoids atmospheric distortion and captures high-resolution observations in ultraviolet, visible, and near-infrared light.
Named after American astronomer Edwin Hubble, the telescope was inspired by Lyman Spitzer’s 1946 proposal to place telescopes in space. Hubble features a 2.4-meter primary mirror and a suite of scientific instruments designed to be upgraded during space servicing missions.
Soon after deployment, a flaw was discovered in the shape of its primary mirror, which was corrected by astronauts during the first servicing mission in 1993. Over its lifetime, Hubble received five servicing missions, which not only fixed technical issues but also significantly upgraded its capabilities.
Hubble has transformed our understanding of the universe. It helped determine the age of the universe (~13.8 billion years), provided evidence for the acceleration of cosmic expansion due to dark energy, revealed the presence of supermassive black holes in galaxies, and observed planets outside our solar system.
Iconic images captured by Hubble—such as the Pillars of Creation and the Hubble Deep Field—have expanded public engagement with space and allowed astronomers to peer billions of years into the past, studying galaxy formation and cosmic evolution.
Now operating alongside the James Webb Space Telescope, Hubble continues to provide critical observations despite aging hardware, including issues with gyroscopes. Its contributions to astronomy remain unparalleled, offering a legacy of scientific discovery and technological achievement.
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APODs including "Hubble Space Telescope"
NGC 1300: Barred Spiral Galaxy
17 May 2026
Across the center of this spiral galaxy is a bar. And at the center of this bar is smaller spiral. And at the center of that spiral is a supermassive black hole. This all happens in the big, beautiful, barred spiral galaxy cataloged as NGC 1300, a galaxy that lies some 70 million light-years away toward the constellation of the river Eridanus. This Hubble Space Telescope composite view of the gorgeous island universe is one of the most detailed Hubble images ever made of a complete galaxy. NGC 1300 spans over 100,000 light-years and the Hubble image reveals striking details of the galaxy's dominant central bar and majestic spiral arms. How the giant bar formed, how it remains, and how it affects star formation remains an active topic of research. Jigsaw Universe: Astronomy Puzzle of the Day