(THEME)

VOICE ONE:

This is Science in the News, in VOA Special English. I'm BobDoughty.

VOICE TWO:

And I'm Sarah Long. This week: meet Sedna the planetoid.

VOICE ONE:

Learn how satellites may give early warning of disease outbreaks.

VOICE TWO:

Also, a study of sexually transmitted diseases in youngAmericans.

VOICE ONE:

And a report on World TB Day, all coming up.

(THEME)

VOICE TWO:

Scientists have found an objectfar away in our solar system. They say it is planet-like. They arecalling it a planetoid.

The red object is thirteen-thousand-million kilometers fromEarth. But it will get ten times farther. It is the most distantobject known to orbit the sun. The discovery means that the solarsystem is bigger than scientists thought.

NASA, the American space agency, helped pay for the research.Michael Brown of the California Institute of Technology, Caltech, inPasadena led the team. Chad Trujillo of Gemini Observatory in Hilo,Hawaii, also took part. So did David Rabinowitz of Yale Universityin New Haven, Connecticut.

VOICE ONE:

The three scientists first saw theobject in November though a telescope at the Palomar Observatory inCalifornia. They named it Sedna, after a goddess of the Inuit peopleof the Arctic. Tradition says she lived in an icy cave at the bottomof the ocean and created the sea creatures of the Arctic.

But Sedna the planetoid is in a much colder place. The scientistsestimate the surface temperature at about two-hundred-forty degreesbelow zero Celsius. When Sedna is even farther from the sun, thetemperature drops close to what scientists call absolute zero. Thisis minus two-hundred-seventy-three degrees Celsius. In theory, thisis as cold as cold can get.

VOICE TWO:

So why is Sedna called a planetoid, and not our tenth planet?Mostly because of its size. The scientists measure Sedna at aboutone-thousand-seven-hundred kilometers around. This is abouttwenty-five percent smaller than the smallest planet, Pluto.

Sedna also has an unusual orbit. The shape is much moreelliptical than the orbits of most of the planets. Picture a circlestretched far from two opposite points.

So how far away does Sedna get? Consider it this way: Sedna takesmore than ten-thousand years to travel around the sun. Earth takesone year.

VOICE ONE:

Michael Brown at Caltech says the planetoid is evidence of whatscientists call the Oort Cloud. This is an area of comets that orbitthe sun, at least in theory. But others think Sedna is more likelypart of the Kuiper Belt. This is an area of asteroids and otherobjects in orbit.

Either way, the scientists all seem to agree that Sedna may tellmuch about the history of our solar system.

(MUSIC)

Here on Earth, NASA scientists think satellites can tell when andwhere diseases might appear. The idea is to look for environmentalconditions that increase populations of insects like mosquitoes thatspread malaria.

VOICE ONE (CONT):

Ronald Welch works at the NASA Global Hydrology and ClimateCenter in Huntsville, Alabama. Mister Welch says scientists andhealth workers are now visiting places where diseases have alreadyappeared. They are also studying satellite images to see how theseareas look from space.

NASA says a Russian scientist, E.N. Pavlovsky, first expressedsuch an idea in the nineteen-sixties.

VOICE TWO:

Ronald Welch is working with health officials in India to developan early warning system. They are working in an area of more thanfour-hundred villages south of New Delhi. Mister Welch says the hopein the near future is to provide about a one-month warning before amalaria outbreak.

Mosquitoes lay their eggs in water. Satellites would find an areawith a lot of rainwater on the ground. Scientists also know thattemperatures must be at least eighteen-degrees Celsius for thedisease to survive in the mosquitoes. When conditions seem right formalaria to appear, workers would go to the area. They would spraychemicals to kill the young mosquitoes before they leave the water.

(MUSIC)

VOICE ONE:

This is Science in the News, in VOA Special English.

Wednesday, March twenty-fourth, is World TB Day. TB is the lungdisease tuberculosis. India will lead the observance this year withpublic health events. Health experts say a new person is infectedwith TB somewhere in the world every second. Then they spread thebacteria through the air when they cough or sneeze.

The problem is even more serious among refugees. The World HealthOrganization says half of all refugees may be infected with TB.Refugees often live in crowded conditions and do not have enoughfood or health care.

Many people leave refugee camps to look for work or familymembers, or to return home. If they start treatment in the camp, butdiscontinue it when they leave, the infection may stay in theirbodies. Then the disease becomes harder to cure, and easier tospread.

VOICE TWO:

Medicine can take six to eight months to cure TB. But doctors saya person who takes the medicine stops infecting other people inabout two weeks.

The World Health Organization says refugees with TB should take acombination of four medicines for at least two to three months. Thenthey are close to being cured and will not spread the infection.

Tuberculosis in children may affect any part of the body.Children should be examined for TB if they are sick for more thanten days. Weight loss and a lack of energy are two possible signs.Children should also be examined if they live close to someone withTB.

VOICE ONE:

Experts say mothers who are infected with TB should continue tobreastfeed their babies. Mother's milk helps protect babies againstdisease. Babies may die from other diseases if they stop nursing.

Also, health workers urge people to cover their mouth when theycough. And people should not discontinue their medicine when theybegin to feel better. They must continue to take the medicine tokill all the germs.

(MUSIC)

VOICE TWO:

Now we talk about another way diseases are spread.

Researchers have just published a study of sexually transmitteddiseases in the United States in two-thousand. They say there werenineteen-million new cases that year. Almost half were in peoplebetween the ages of fifteen and twenty-four. Yet people in this agegroup represent only twenty-five percent of what the researcherscall the sexually experienced population.

Researchers from the Centers for Disease Control and Preventionwrote two reports. Both appear in Perspectives in Sexual andReproductive Health, published by the Alan Guttmacher Institute.

Sharon Camp heads this non-profit group in New York. She saysmost young people are sexually active. However, she says many arepoorly equipped to prevent infections or to seek testing andtreatment.

VOICE ONE:

The researchers say nine-million infections were reported inyoung people in two-thousand. They estimate the cost to treat thesepeople over their lifetimes could reach more thansix-thousand-million dollars. Most of the cost is connected to thetreatment of H.I.V., the virus that causes AIDS.

But AIDS is not the only threat from sexually transmitteddiseases. Three other diseases represent almost ninety percent ofall new cases among people in the United States age fifteen totwenty-four.

One is the human papillomavirus. H.P.V is usually harmless andgoes away. But some forms can cause cervical cancer and otherconditions. The two other diseases are trichomoniasis and chlamydia.Doctors treat these with antibiotics. Yet many people never knowthey have a sexually transmitted disease, unless they go for a test.

VOICE ONE:

Health experts and a group of young people prepared a separatereport released by the University of North Carolina.

It says programs that only teach young people not to have sexuntil marriage will not control the spread of disease. In January,President Bush proposed a one-hundred-percent increase in federalmoney for programs that teach abstinence.

The report says young people need to learn about abstinence. Butit says they also need realistic advice about other ways to preventinfection.

(THEME)

VOICE TWO:

SCIENCE IN THE NEWS was written by Caty Weaver, Paul Thompson,Karen Leggett and Cynthia Kirk, who was also our producer. I'm SarahLong.

VOICE ONE:

And I'm Bob Doughty. Join us next week for more news aboutscience, in Special English, on the Voice of America.