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Why
do we need a space telescope?
Ever since 1609 when Galileo used first used a telescope
to view the night sky, humans have been building ever
larger and better telescopes which allowed us to see
farther and farther out into space. Objects that were
once invisible came into view, and with each advance in
technology we were able to discover and examine objects
located at greater distances from the earth.
But there was a serious problem that hindered
astronomers in their efforts to see vast distances: the
earth's atmosphere. The atmospheric gases distort light
as it passes through them. This phenomenon is what gives
stars their "twinkle". It also blurs the images of
distant objects viewed through a telescope.
Ever since the 1940's, astronomers have dreamed of
placing a telescope in space where they would be
unaffected by the atmosphere. In the 1970s, NASA and the
European
Space Agency started a joint venture to build a
space telescope and place it into orbit around the
earth.
It was decided that the remarkable device would be named
after Hubble in recognition for his numerous
contributions to the science of astronomy. The
astronauts aboard the space shuttle Discovery
successfully placed the Hubble Space Telescope
into orbit some 380 miles above the earth's surface on
April 25, 1990.
The Hubble Space
Telescope is seen during servicing in a 2002 file photo. NASA
managers debated on Friday whether to risk a space shuttle flight on
a mission to extend the life of the Hubble Space Telescope.
(NASA/Handout/Reuters)
The
Hubble Space Telescope is shown in this 2002 file photo.
(AP Photo/NASA, FILE)
Astronaut
Richard Linnehan attaches light shields to the Hubble telescope in a
Monday, March 4, 2002 file photo, as shown in this image from
television. The fate of what some scientists call 'the people's
telescope' is up in the air again as NASA decides in the next week
or two whether to squeeze in a last shuttle repair mission to give
the Hubble Space Telescope several more years of life. (AP
Photo/NASA TV, File)
This image from
NASA's Spitzer Space Telescope and provided Thursday Oct. 26, 2006
shows the scattered remains of an exploded star named Cassiopeia A.
Spitzer's infrared detectors 'picked' through these remains and
found that much of the star's original layering had been preserved.
In this false-color image, the faint, blue glow surrounding the dead
star is material that was energized by a shock wave, called the
forward shock, which was created when the star blew up. The forward
shock is now located at the outer edge of the blue glow. Stars are
also seen in blue. Green, yellow and red primarily represent
material that was ejected in the explosion and heated by a slower
shock wave, called the reverse shock wave. (AP Photo/NASA)
An artist's
impression shows a unique type of exoplanet discovered with the
Hubble Space Telescope. The planet is so close it to its star that
it completes an orbit in 10.5 hours. The planet is only 750,000
miles from the star, or 1/130th the distance between Earth and the
Sun. The Jupiter-sized planet orbits an unnamed red dwarf star that
lies in the direction of the Galactic Centre; the exact stellar
distance is unknown. (Schaller/Handout)
This Hubble
image of the Antennae galaxies is the sharpest yet of this merging
pair of galaxies. As the two galaxies smash together, billions of
stars are born, mostly in groups and clusters of stars. The
brightest and most compact of these are called super star clusters.
(REUTERS/NASA, ESA/Hubble, and B. Whitmore (Space Telescope Science
Institute)/Handout)
The
Andromeda spiral galaxy is shown in this infrared image
taken by NASA's Spitzer Space Telescope and released by
on October 18, 2006. Astronomers have new evidence that
the Andromeda spiral galaxy was involved in a violent
head-on collision with the neighboring dwarf galaxy
Messier 32 (M32) more than 200 million years ago.
(REUTERS/NASA/JPL-Caltech/D. Block (Anglo American
Cosmic Dust Lab, SA)/Handout)
The Orion Nebula
God's work is so awesome, isn't it?
This
image of the Orion Nebula, taken by NASA's Spitzer and
Hubble Space Telescopes and released November 7, 2006,
shows an infrared and visible-light composite that
indicates that a 'gang' of four monstrously massive
stars at the center of the cloud may be the main
culprits of mayhem in the familiar Orion constellation.
The stars are collectively called the 'Trapezium' and
can be communally identified as the yellow smudge near
the center of the image. Swirls of green in Hubble's
ultraviolet and visible-light view reveal hydrogen and
sulfur gas that have been heated and ionized by intense
ultraviolet radiation from the Trapezium's stars.
REUTERS/ NASA/JPL-Caltech/T. Megeath (University of
Toledo) & M. Robberto
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