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Hubble Space Telescope

Hubble Space Telescope's Name: 
NASA named the world's first space-based optical telescope after American astronomer Edwin P. Hubble (1889–1953). Dr. Hubble confirmed an "expanding" universe, which provided the foundation for the Big Bang theory.

Cool Fact:
Scientists believe our universe began with a “big bang” some 13.7 billion years ago. If all the events in the history of the universe until now were squeezed into 24 hours, Earth wouldn’t form until late afternoon and humans would have existed for only 2 seconds.

Hubbles Space Telescope Mission: 
  • Launch: April 24, 1990 from space shuttle Discovery (STS-31)
  • Deployment: April 25, 1990
  • Mission Duration: Up to 20 years
  • Servicing Mission 1: December 1993
  • Servicing Mission 2: February 1997
  • Servicing Mission 3A: December 1999
  • Servicing Mission 3B: February 2002
Hubbles Space Telescope Size: 
  • Length: 43.5 ft (13.2 m)
  • Weight: 24,500 lb (11,110 kg)
  • Maximum Diameter: 14 ft (4.2 m)
    Hubble is nearly the size of a large school bus—but it can fit inside a space shuttle cargo bay.
Cost at Launch: 
$1.5 billion

Spaceflight Statistics:
The Hubble Space Telescope whirls around Earth at a speed of 5 miles per second. If cars moved that fast, a coast-to-coast trip across the continental United States would take only 10 minutes. Orbit: At an altitude of 307 nautical miles (569 km, or 353 miles), inclined 28.5 degrees to the equator (low-Earth orbit)

  • Time to Complete One Orbit: 97 minutes
  • Speed: 17,500 mph (28,000 kph)


Optical Capabilities: 
Hubble Can’t Observe: The Sun or Mercury, which is too close to the Sun.
  • Sensitivity to Light: Ultraviolet through infrared (115–2500 nanometers)
  • First Image: May 20, 1990: Star Cluster NGC 3532
The most frequently observed celestial object is Earth. Earth is observed regularly for calibration—to make sure that all the charge-coupled detectors (CCDs) are working properly. The images from these "test" observations show no detail.


Data Stats: 
Hubble transmits about 120 gigabytes of science data every week. That's equal to about 3,600 feet (1,097 meters) of books on a shelf. The rapidly growing collection of pictures and data is stored on magneto-optical disks.

Power Needs:

  • Energy source: the Sun
  • Mechanism: two 25-foot solar panels
  • Power usage: 2,800 watts
In an average orbit, Hubble uses about the same amount of energy as 28 100-watt light bulbs.


Pointing Accuracy: 
In order to take images of distant, faint objects, Hubble must be extremely steady and accurate. The telescope is able to lock onto a target without deviating more than 7/1000th of an arcsecond, or about the width of a human hair seen at a distance of 1 mile. Pointing the Hubble Space Telescope and locking onto distant celestial targets is like holding a laser light steady on a dime that is 200 miles away.

Hubble Space Telescope's mirrors:

  • Primary Mirror
    • Diameter: 94.5 in (2.4 m)
    • Weight: 1,825 lb (828 kg)
  • Secondary Mirror
    • Diameter: 12 in (0.3 m)
    • Weight: 27.4 lb (12.3 kg)
Hubble's two mirrors were ground so that they do not deviate from a perfect curve by more than 1/800,000ths of an inch. If Hubble’s primary mirror were scaled up to the diameter of the Earth, the biggest bump would be only six inches tall.

Power Storage:

  • Batteries: 6 nickel-hydrogen (NiH)
  • Storage capacity: equal to 20 car batteries

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