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SCIENCE IN THE NEWS - Flight to Service Hubble Telescope Could Take Place in Early 2008

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VOICE ONE:

This is SCIENCE IN THE NEWS in VOA Special English. I'm Doug Johnson.

VOICE TWO:

And I'm Faith Lapidus. This week: The future suddenly looks brighter for the Hubble Space Telescope.

VOICE ONE:

Move over, Mickey Mouse -- meet the Cypriot mouse.

VOICE TWO:

Also, a technology report on a new cookstove for refugee camps in Darfur.

VOICE ONE:

And we tell you about a water-purifying device called the LifeStraw.

(MUSIC)

VOICE TWO:

Hubble Space Telescope
Hubble Space Telescope

The American space agency has decided to extend the life of the Hubble Space Telescope.

The orbiting observatory is sixteen years old. Over the years, space shuttle astronauts have flown to the Hubble four times to make repairs and improvements. A fifth visit had been set for last year.

But in two thousand four, NASA's administrator at the time, Sean O'Keefe, vetoed the plan. He said it would be too risky. At that time all shuttle flights were suspended following the loss of the shuttle Columbia in two thousand three.

What about designing a robotic spacecraft to repair Hubble? Studies showed that would be too costly and too complex to attempt by two thousand seven. Engineers thought Hubble could fail next year because of weakening batteries and aging gyroscopes. The gyroscopes are part of Hubble's guidance system. They help keep the telescope pointed in the right direction.

Now, the current NASA administrator has renewed plans to send a shuttle crew on another Hubble repair flight. Michael Griffin announced the decision last week. He said he would not have agreed to it if he did not believe the plan could succeed, and succeed safely.

VOICE ONE:

NASA, the National Aeronautics and Space Administration, is preparing to retire its space shuttles. But before then, under the new plan, the shuttle Discovery will fly to the Hubble telescope. It could happen as early as May of two thousand eight. The seven-member crew will carry out repairs and add new equipment, including two new camera instruments. The hope is to keep Hubble operating until two thousand thirteen.

NASA chief Michael Griffin says the repair mission can wait until two thousand eight. Engineers have found ways to extend the life of Hubble's batteries and gyroscopes. But even if those systems fail before then, he says, Hubble could operate in a so-called safe mode until the astronauts arrive.

The telescope orbits six hundred kilometers above the Earth. Its images of the universe have led to a great many discoveries.

Michael Bakich at Astronomy magazine was among those very happy at NASA's decision. He calls the Hubble Space Telescope one of the great machines of all time.

(MUSIC)

VOICE TWO:

You are listening to SCIENCE IN THE NEWS in VOA Special English.

Thomas Cucchi is a French archeologist working at Durham University in England. He is an expert on the history of house mice.

Two years ago, he was on the island of Cyprus examining fossil remains of mice that lived during the Stone Age. He was comparing their teeth with those of modern European house mice. In the process, he identified a population of mice that live on Cyprus but are different from other European mice.

The archeologist says they must have arrived on Cyprus before the island broke away from the mainland. He says the mouse colonized and changed to survive the Cypriot environment several thousand years before humans arrived. Humans are believed to have settled on the island ten thousand years ago.

VOICE ONE:

Photo released by Durham University of Mus cypriacus, the newly identified mouse species on Cyprus
Photo released by Durham University of Mus cypriacus, the newly identified mouse species on Cyprus

Genetic tests at the University of Montpellier in France confirmed that the mouse is a different species. The scientific name is Mus cypriacus. It has a bigger head, ears, eyes and teeth than other European mice. Still, most people might mistake it for one of the common European house mice that also live on the island.

But Thomas Cucchi calls it a living fossil. He and other scientists described the new mouse in a report earlier this year in the publication Zootaxa. He says the mystery behind its survival offers a new area of study. He notes that most mammals disappeared from Mediterranean islands after humans arrived. The exceptions are two kinds of shrews, and now this mouse.

Mammals are warm-blooded creatures that have hair and drink milk from their mothers. The new species of mouse is one of about twelve kinds of mammals discovered in the world in the past few years. But the discovery of a new mammal species in Europe surprised scientists.

Mister Cucchi says new mammal species are mainly discovered in areas like Southeast Asia. They are generally found in areas where few people live and where scientific visits are rare. He notes that scientists generally believed that all the mammals in Europe had already been identified.

(MUSIC)

VOICE TWO:

Scientists have designed a cookstove that could make life a little easier for refugees in the Darfur area of Sudan. It might also help reduce the loss of forests in poor countries where trees are cut down as fuel for cooking fires. The scientists are from the Lawrence Berkeley National Laboratory and the University of California, Berkeley.

Two of them, Ashok Gadgil [ah-SHOKE GAD-gil] and Christina Galitsky, went to Darfur late last year. They found that many refugee families were missing meals for lack of fuel.

The light metal stove uses only about one-fourth as much wood as the cooking method currently used in the camps. That method is known as the three-stone fire. Less need for fuel would mean less need for women to leave the camps to search for wood and risk being attacked in violence-torn Darfur.

VOICE ONE:

Since that visit, the researchers have improved the stove. Now they are trying to set up production. They estimate that the stoves could be built locally in Darfur for about fifteen dollars each. They say about three hundred thousand are needed. The hope is to begin producing five thousand stoves by the end of the year.

Ashok Gadgil says his team agrees with aid organizations that the stoves should not be given away free of charge. If they are free, he says, they will be undervalued. People might then try to sell them for the value of the metal. The scientists say microlending programs could help people buy the stoves with loans if they do not have enough money. And people could use borrowed money to start their own stove-building business.

VOICE TWO:

San Francisco area members of Engineers Without Borders-USA are providing engineering support for the project. The groups working on the Darfur Cookstoves Project are also seeking donations to support their work.

The project has a Web site. The address is darfurstoves.lbl.gov.

VOICE ONE:

During the nineteen nineties, Ashok Gadgil invented a water-purifying system that won awards for its design. The system is called UV Waterworks. It uses ultraviolet light to disinfect water of viruses and bacteria. And it can be powered by a car battery or energy from the sun.

Now there is another award-winning water-purifying device on the market. The Vestergaard Frandsen Group, a Danish company with headquarters in Switzerland, invented the LifeStraw last year. The LifeStraw won an award from a nonprofit organization in Denmark that honors designs to improve life.

VOICE TWO:

The LifeStraw is a thick plastic tube twenty-five centimeters long. You place one end into water and drink from the other. The water passes through a series of filters to catch extremely small particles. Iodine and active carbon are also used in the cleaning process. It takes about eight minutes to filter one liter.

Vestergaard Frandsen says the LifeStraw kills organisms that spread diarrhea, dysentery, typhoid and cholera. The device filters most bacteria and parasites. But it has limits, including against viruses. Also, it does not remove arsenic or other heavy metals from water.

VOICE ONE:

The LifeStraw costs about three dollars. It can be worn on a string around the neck. It has a lifetime of up to seven hundred liters, or about one year.

The company notes that each day, worldwide, more than six thousand children and adults die from unsafe drinking water.

(MUSIC)

VOICE TWO:

SCIENCE IN THE NEWS was written by Jerilyn Watson and Jill Moss. I'm Faith Lapidus.

VOICE ONE:

And I'm Doug Johnson. Learn more about science, and download transcripts and MP3 files of our programs, at www.unsv.com And join us again next week for more news about science in Special English on the Voice of America.

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