SCIENCE IN THE NEWS(在线收听

SCIENCE IN THE NEWS - October 29, 2002: Distant Object in Solar System / Physicist Dismissed Over
Claims / Biological Pacemaker


VOICE ONE:
This is Steve Ember.
VOICE TWO:
And this is Bob Doughty with Science in the News, a VOA Special English program about recent developments


in science. Today, we tell about a new object discovered far away in the solar system. We tell about a physicist
who was dismissed for scientific wrongdoing. And we tell about the development of a biological device to help
the heart beat normally.

((THEME))
VOICE ONE:


American astronomers have discovered a new object in our solar system, further
away from Earth than the planet Pluto. It is the largest object discovered in the solar
system since the discovery of Pluto in nineteen-thirty. It is also the farthest object in
the solar system to be seen by a telescope. Scientists call the object “Quaoar”
(KWAH-o-ar). It is about half the size of Pluto, too small to be considered a planet.

Scientists estimate that Quaoar takes about two-hundred-eighty-eight years to orbit
the sun. Astronomers call the area beyond Pluto the Kuiper (KY-per) Belt. It is a
distant and dark area that contains objects that are made mostly of frozen gases.

VOICE TWO:

Two astronomers from the California Institute of Technology made the discovery in June. They used a telescope
at Mount Palomar Observatory near Pasadena. However, Chadwick Trujillo (tru-HE-oh) and Michael Brown did
not announce their discovery immediately. Instead, they gathered more information about the object. They used
the Hubble Space Telescope to discover the size of the object. They also found what the new object was made of.

Mister Brown and Mister Trujillo found that Quaoar is made of ice and rock. It contains substances like carbon
dioxide, methane and even water. However, it is so far from the sun that even gases like carbon dioxide are
frozen solid.

The astronomers chose the name Quaoar from the Native American tradition of the Tongva people. They once
lived near Los Angeles and not too far from the observatory where Mister Trujillo and Mister Brown discovered
the object. Quaoar means the “great force of creation”
in the Tongva language.

VOICE ONE:

The discovery of Quaoar has again raised questions about Pluto. Astronomers are no longer sure that Pluto
should be considered a planet. Quaoar appears to be very similar in size and material. Pluto and Quaoar might
represent a separate kind of object from the Kuiper Belt. Astronomers are considering changing what they call
Pluto. Instead of a planet, it may be called a Kuiper Belt object in the future.

Yet there are differences between Pluto and the new object. Pluto is two-thousand-three-hundred kilometers
across. Quaoar is only about one-thousand-two-hundred kilometers across. Pluto has a moon, called Charon,
which is about the size of Quaoar itself. However, some scientists consider these differences unimportant.

VOICE TWO:


The discovery of Quaoar may be part of a historic change in the way astronomers think about the solar system. A
similar change happened in eighteen-oh-one. That year, the astronomer Guiseppe Piazzi in Palermo, Italy,
discovered what he thought was a planet.

Mister Piazzi found an object moving in between the orbits of Mars and Jupiter. He suggested the name Ceres.
Within a few years, other astronomers discovered more small objects at about the same distance from the sun as
Ceres. Today, we call these small objects, made of rock and metal, asteroids. Quaoar also may be one of many
new discoveries.

VOICE ONE:

Mister Trujillo and Mister Brown believe there may be twenty more objects like Quaoar in the solar system. Most
astronomers believe there are many more objects to be discovered in the distant Kuiper Belt. Perhaps Pluto is
only the first of many similar objects orbiting in the darkness far beyond the sun. Astronomers would then have
to change the current model of the solar system.

((MUSIC BRIDGE))

VOICE TWO:

Investigators have found that claims made by scientists at a top American research laboratory were not based on
fact. The investigators dismissed results from a number of studies published between nineteen-ninety-eight and
two-thousand-one.

Some of the claims once were said to be major developments in the study of physics. They included a claim that
the scientists had created the smallest device to carry electrical current ever made.

VOICE ONE:

Bell Labs in Murray Hill, New Jersey, ordered the investigation in May after other scientists raised questions
about the claims. Bell Labs appointed a committee to investigate twenty-four accusations of scientific
wrongdoing.

The committee identified at least sixteen examples of scientific wrongdoing. It placed the
blame on one Bell Labs physicist, Jan Hendrik Schon (YAHN HEN-drick SHERN).
Mister Schon told the committee that he had no written records of the laboratory
experiments. He also said much of the information in his computer had been destroyed.

VOICE TWO:

The investigators found that Mister Schon used information from earlier work to support
his findings. They said he did this without the knowledge of the other scientists involved
in the experiments. The investigators noted that Mister Schon and his group produced an
average of one scientific paper every eight days. For most scientists, a few papers a year is considered productive.

After the committee’s report was released, Bell Labs immediately dismissed Jan Hendrik Schon from his
position. He was once thought to be a future Nobel Prize winner. After his dismissal, Mister Schon admitted he
had made mistakes in his scientific work. He said he regretted those mistakes. He also said he believes the results
reported in the studies are real.

The incident has damaged the work of the other Bell Labs scientists who failed to report any problem. It also is
bad news for Lucent Technologies, the company that operates Bell Labs. The company has been struggling with
a series of financial problems during the past two years.Other scientists have criticized the magazines that
published the results. Critics say the publications moved too quickly to report on the studies.

((MUSIC BRIDGE))

VOICE ONE:

A healthy human heart normally has a small group of special cells called pacemaker cells. Pacemaker cells



produce an electrical current that causes the heart to beat. However, old age or disease can cause these cells to
fail. Doctors use electronic pacemaker devices to fix the problem. In the United States, the small devices are
placed in about two-hundred-fifty-thousand patients each year.

Now, scientists in the United States have used genetic engineering to create a kind of biological pacemaker in
guinea pigs. Their findings suggest that genetically engineered heart cells could one day be developed for
humans. Such cells could possibly replace the electronic pacemakers currently used in many patients with heart
disease.

VOICE TWO:

Scientists at Johns Hopkins University in Baltimore, Maryland, led the new study. They found they could use the
chemical potassium to trick normal heart cells in guinea pigs to act like pacemaker cells. Most heart muscle cells
do not have the right level of potassium to produce electricity on their own.

Nature magazine reported that the scientists used a virus to carry a gene that changed the balance of potassium.
They injected the virus into the heart cells of guinea pigs. A few days later, some of the heart muscle cells in the
animals began to act like pacemaker cells.

VOICE ONE:

Eduardo Marban (mar-BAN) was a member of the Johns Hopkins team. He said the research may lead to new
treatments for people who need electronic pacemakers. He said it may be possible in the future to recreate
pacemaker cells in humans. Or scientists may be able to develop other pacemakers that are part electronic and
part biological.

Doctor Marban said a biological pacemaker should be able to react to the body’s changing needs. He noted that
an electronic pacemaker, in its simplest form, does not.

The scientists said that more work needs to be done before a biological pacemaker can be tested in humans.

((THEME))

VOICE TWO:

This SCIENCE IN THE NEWS program was written by Mario Ritter and George Grow. It was produced by
Cynthia Kirk. This is Bob Doughty.

VOICE ONE:

And this is Steve Ember. Join us again next week for more news about science in Special English on the Voice of
America.


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