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STS-125 Info Orb Text

STS-125 mission patch

STS-125 Mission Patch

The Hubble Space Telescope is on the STS-125 patch. The blue field of planets, stars and galaxies stands for the universe. The black background represents dark energy and dark matter in space. The red border around the crew members' names stands for the red shift of light that shows how the universe is expanding.
STS-125 crew

STS-125 Crew

The STS-125 crew will update and service NASA's Hubble Space Telescope. From the left are astronauts Mike Massimino and Michael Good, both mission specialists; Gregory C. Johnson, pilot; Scott Altman, commander; and Megan McArthur, John Grunsfeld and Andrew Feustel, all mission specialists.
Divers training with astronauts on the mock-up of NASA's Hubble Space Telescope


The STS-125 space shuttle crew trained for the 11-day spaceflight. The mission will improve Hubble by 10 to 70 times. Astronauts will make five spacewalks to install, service and update equipment. The crew also will replace batteries and gyroscopes. These upgrades and repairs should make Hubble continue to work for at least five more years.

Hubble orbiting above Earth with the blackness of space behind

Hubble Spacecraft

Hubble is not just a telescope -- it orbits like a spacecraft. Four antennae send and receive information between the telescope and the Flight Operations Team on Earth. Scientists communicate with the telescope via a system of satellites, similar to controlling a robot remotely.

Computer-animated drawing of Hubble attached to the space shuttle's robotic arm

Hubble Space Telescope

Hubble has been in space since April 1990. It is about the size of a large school bus. Every 96 minutes, Hubble completes an orbit about 350 miles above Earth. This distance is more than 100 miles higher than the International Space Station. On Aug. 11, 2008, Hubble made its 100,000th orbit around Earth.

Computer animation of astronauts installing the Wide Field Camera 3

Wide Field Camera 3

The STS-125 crew will install Wide Field Camera 3. The camera can detect three types of light: ultraviolet, visible and near infrared. UV is the kind of radiation that causes sunburn. Visible is the light that human eyes can see. NIR is the radiation seen with night-vision goggles. The new camera will produce images that are about 35 times better than the current camera's.

Cosmic Origins Spectrograph

Cosmic Origins Spectrograph

The crew will install a new instrument, the Cosmic Origins Spectrograph. It will allow the telescope to find low levels of light. A spectrograph captures the light of objects and breaks the light into colors. Scientists know the chemical elements that make up an object by these colors. The data from the COS will help reveal the origins of the universe.

Fine Guidance System being lifted

New Fine Guidance Sensor

Hubble has tools to help target an object. The STS-125 mission will install a refurbished Fine Guidance Sensor that will improve Hubble's "pointing control system." The FGS along with the gyroscopes will allow Hubble to aim steadily at an object. The result will make Hubble's aim so precise that using it will be like pointing a laser beam at a dime 200 miles away.

Computer animation of astronauts installing a Rate Sensor Unit that holds gyroscopes

New Gyroscopes

STS-125 astronauts will replace all six of Hubble's gyroscopes. Gyros always face the same direction, like the needle of a compass. They sense the telescope's angular motion and provide a short-term reference point to help Hubble zero in on its target. Two gyros are housed in each of three Rate Sensor Units.

One battery module holds three batteries

New Batteries

The astronauts will replace the telescope's six 125-pound nickel hydrogen batteries that have been in Hubble for 19 years. The telescope is in sunlight for about 61 minutes of its 96-minute orbit. Solar arrays power the electrical equipment and charge the batteries during this time. During the 35 minutes Hubble is in Earth's shadow (night), the batteries power the spacecraft.

The Sombrero Galaxy in infrared light

Hubble Pictures

Hubble is a space telescope. It provides dazzling images of the universe. Being in space lets Hubble take better pictures. Earth's atmosphere blocks out some electromagnetic radiation including X-rays and gamma rays. Infrared and ultraviolet rays are partly blocked. Above the atmosphere, space telescopes can see all wavelengths of light.

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