Hubble Fun Facts

Fun Facts about the Hubble Space Telescope

  1. The Hubble Space Telescope (HST) orbits the Earth at an altitude of about 340 miles (547 kilometers) and travels at a speed of about 17,000 miles per hour (27,300 kilometers per hour). It takes Hubble about 95 minutes to complete one orbit around Earth.

  2. The HST cannot track an object on Earth; a photo taken of Earth would be completely streaked because the surface of the Earth is quickly whizzing by as Hubble orbits. The shortest exposure time on any of the Hubble instruments is 0.1 seconds, and in this time Hubble moves almost half a mile, about 700 meters.

  3. There are no natural color cameras aboard Hubble and there never have been. The optical cameras on board have all been digital charged-coupled device (CCD) cameras, which take images as grayscale pixels but use colored filters to isolate different colors in each image.

  4. Hubble has made more than 1.5 million observations since its mission began in 1990 and generates about 10 terabytes of new data per year. The total archive is currently over 340 TB in size.

  5. Hubble has no thrusters. To change angles, it uses Newton’s third law by spinning its wheels in the opposite direction. It turns at about the speed of a minute hand on a clock, taking 15 minutes to turn 90 degrees.

  6. The HST is able to lock onto a target without deviating more than 7-thousandths (0.007) of an arcsecond - equivalent to shining a laser on a human hair one mile away. Also, due to the combination of optics and sensitive detectors and with no atmosphere to interfere with the light reaching it, Hubble can spot a night light on the surface of the Moon from Earth.

  7. Hubble technology helped lead to better methods for detecting breast cancer. The HST’s Space Telescope Imaging Spectrograph (STIS) searched for supermassive black holes. NASA’s improvements to the STIS allowed medical professionals to utilize the same silicon chips found in the instrument to more effectively image women’s breast tissue and distinguish between benign and malignant tumors.

  8. Only about one-fifth of the hundreds of astronomers each year who apply to use the Hubble are awarded time with the HST. Everyone else has access to the HST archives, all of which are available to the public following a one-year waiting period.

  9. The estimated cost for the entire Hubble Space Telescope mission since its official start in 1977, including space shuttle servicing missions, is approximately $20 billion (adjusted for inflation to 2021 dollars).

  10. Hubble’s curved mirror focuses starlight and is located deep inside the telescope, protected by its long tube-like structure. With no atmosphere around Hubble and its protective housing, there is no risk of dust or corrosion reaching inside and therefore the mirrors need no cleaning.