EXPLORATIONS -May 8, 2002: Hubble's New Camera
By Paul Thompson
VOICE ONE:
This is Mary Tillotson.
VOICE TWO:
And this is Steve Ember with the VOA Special English program EXPLORATIONS.
Last week, the National Aeronautics and Space Administration released four new pictures. They were taken by
the Hubble Space Telescope’s new Advanced Camera for Surveys. Today we tell about the photographs the
camera took and the excitement they have caused among scientists who study the universe.
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VOICE ONE:
Holland Ford is a scientist at Johns Hopkins University, in Baltimore, Maryland. He
is also the leading scientist for Hubble Space Telescope’s new Advanced Camera
for Surveys known as A-S-C.
The new camera was expected to give the Hubble telescope ten times more power than the older camera on
Hubble. NASA scientists say the new camera is much better than expected.
Mister Ford said he and his team of scientists were shocked and surprised by Hubble ’s increased power. He said
the new camera is like having a new window that permits us to see the universe. He said this new window is very
large and extremely clear. Mister Ford said, “We can now see galaxy after galaxy.
”
VOICE TWO:
NASA released four photographs taken by the space telescope. One of the photographs shows the Omega
Nebula. There are hundreds of stars in this Nebula, surrounded by clouds of cold, dark hydrogen. Omega is also
called the Swan Nebula and is about five-thousand-five hundred light years away from Earth in the constellation
Sagittarius.
A photograph of the Cone Nebula was also released. It is a beautiful red color. It
shows a tall structure made of gas and dust with many bright stars near the top.
Another photograph shows two small galaxies named the Mice. They are three
hundred million light years away from Earth. They seem to be chasing each other.
However, they are about to crash together.
VOICE ONE:
Perhaps the most exciting picture shows a galaxy four-hundred-twenty-million light-
years from Earth. The galaxy is called the Tadpole. The Tadpole is a group of stars
that seems to be spinning in space, surrounded by clouds of gas. It has a long tail of
stars that follow behind it. The galaxy is shaped like a tadpole, which is a small,
developing toad or frog with a big head and long tail. NASA says the galaxy has this
unusual shape because it is really two galaxies that crashed into each other millions
of years ago.
The photograph of the Tadpole Galaxy is extremely
beautiful. Mister Ford was quick to say that the photographs were much more than just
pretty pictures. He said the new photographs taken by the A-S-C of the Tadpole show
about six -thousand other galaxies behind it. This is about two times as many as could
be seen by Hubble ’s earlier camera. Hubble first photographed the Tadpole Galaxy in
nineteen-ninety-five.
Mister Ford said some the galaxies behind the Tadpole are more than ten-thousandmillion
light years from Earth. He said this is almost at the edge of the universe that we
can observe. He also said new photographs provide huge amounts of new and valuable
information.
VOICE TWO:
NASA says the new Advanced Camera for Surveys has such great power because it is able to gather very small
amounts of light that come from extreme distances. This amount of light is so small that it can not be seen by the
human eye. The A-S-C takes photographs by gathering these small amounts of light for several hours at a time. It
can then produce a photograph from all the light that has been gathered.
The A-C-S carries equipment that can control light that enters the camera. It does this by placing different pieces
of glass in front of the eye of the camera.
The A-S-C can take photographs of a much larger area than the earlier camera. This will let space scientists see
much larger areas of the universe.
The new camera records what it sees in electronic information called megapixels. This is similar to the electronic
information recorded by electronic or digital cameras that anyone can buy.
The more magapixels a camera has the better the quality of the photograph. Most digital cameras that can be
bought today in a photography store use two to four magapixels to record a picture. Hubble’
s new camera
records with sixteen million magapixels. This means the A-S-C photographs show sharp details of objects farther
away than have been seen before.
VOICE ONE:
Astronomers say the new A-S-C will make it possible to look so far back in time that they can study how stars
and galaxies appeared as they were forming. It will also let astronomers study how these galaxies have changed
through time.
Astronomers also hope to use the new Advanced Camera for Surveys to make maps of galaxies. These maps will
show how different galaxies develop and are held together. They will help researchers better understand how the
universe is expanding. The maps also will permit astronomers to search areas near distant stars for planets that
are similar to Earth.
((MUSIC BRIDGE))
VOICE TWO:
The new Advanced Camera for Surveys is just one of many devices that were repaired or placed in the space
telescope in March. The work was done by the crew of the Space Shuttle Colombia.
The Hubble Space Telescope is the first scientific instrument ever designed to be repaired and rebuilt by
astronauts who work in space. Ninety percent of its parts can be repaired or replaced by space shuttle astronauts.
Besides the A-S-C, the space telescope also received new equipment so it can make electric power from sunlight.
Radiation and small space objects had damaged the old power supply equipment.
The new equipment looks like large wings. The wings are called solar arrays. The new solar arrays are smaller
than the ones they replaced, but they produce twenty-seven percent more power.
VOICE ONE:
Hubble’s electric power control device also was replaced. It now lets the telescope use all of the increased
power provided by the new solar arrays.
Astronauts repaired an instrument called the Near Infrared Camera and Multi-Object Spectrometer. They
replaced the cooling system that the camera needed to operate. A NASA spokesman says the new cooling system
is working well. They hope to release the first photographs from this camera in June.
VOICE TWO:
The space shuttle crew also successfully repaired Hubble ’s communications system and its computers. NASA
says the only repair problem that remains involves the devices that are used to point the telescope at distant
objects.
The Hubble’s pointing system is extremely important. It is used to find and lock the telescope on objects so
they can be studied. The pointing system has a small computer that looks for any movement or mistakes forty
times a second. If movement occurs, spinning wheels change speeds to bring the telescope back into the correct
position.
NASA says the pointing system may have a shorter working life than expected. Experts say it could fail because
it uses more electricity than it should. A second device can be used if the first one fails.
((MUSIC BRIDGE)
)
VOICE ONE:
The Hubble Space Telescope is an eye in space that lets people around the world see pictures of the distant
universe. It orbits six -hundred kilometers above the Earth.
The telescope works twenty-four hours a day, seven days a week helping astronomers unlock the secrets of the
universe. It provides information and photographs of distant parts of the universe that cannot be seen from Earth
because of clouds or atmospheric conditions.
The Hubble Space Telescope has provided thousands of photographs of distant objects in the universe. Many of
these objects are millions of light years away from Earth. The space telescope has provided evidence of the birth
of stars and their deaths.
A NASA official says the space telescope has provided twelve years of great science and wonderful pictures. Yet,
he said, the new camera has already shown us that what we will see in the future will be even more exciting.
VOICE TWO:
If you have a computer that can link with the Internet, you can see several thousand photographs taken by the
Hubble Space Telescope. The four new ones taken by the Advanced Camera for Surveys are among them.
Have your computer search for the word Hubble. That is H-U-B-B-L-E. Your computer will provide several Web
sites that will permit you to see millions of kilometers into our universe.
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)
VOICE ONE:
This Special English program was written by Paul Thompson. It was produced by Cynthia Kirk. Our studio
engineer was Darryl Smith. This is Mary Tillotson.
VOICE TWO:
And this is Steve Ember. Join us again next week for another EXPLORATIONS program on the Voice of
America.
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