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Straight ahead "Our World," The latest from the Huygens mission to Saturn's moon Titan ... Decoding the honeybee genome ... and a modern explanation for an ancient mass extinction.
WARD: "We are seeing, really, an age of mammals at 250 million years ago that is stopped dead in its tracks, literally and figuratively by what I consider a global warming catastrophe."
Those stories, door-to-door flu vaccinations and our Website of the Week. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
One week after the Huygens space probe landed on distant Titan, European and American scientists have revealed startling new information about this largest and most mysterious moon of the planet Saturn, including evidence of flowing streams and liquid methane rainfall. Lisa Bryant has more on these exotic yet earth-like characteristics, described Friday by scientists at the European Space Institute in Paris.
BRYANT: Just a week ago, scientists were applauding the successful landing of the space probe, which plunged through the murky, chilling air of Titan to land on a spongy surface they described as wet sand or soft clay. It appears a mysterious, pinkish orangey world. Pictures sent by the probe showed a flat terrain with fist-sized objects that researchers described as
chunks of ice.
Now, scientists have been able to sift through dozens of images sent by the Huygens space probe over the space of several hours before its batteries went dead. Martin Tomasko, one of the principal investigators for the Titan project, describes some of the grainy, black and white images to reporters.
TOMASKO: This is a field of view one kilometer across and you see this very rugged terrain.... We see a ridge system ....
The pictures show spidery dark lines etched on Titans surface. There are also lighter areas. They appear a mystery to ordinary viewers. But the projects scientists believe they are rivers, streams and channels of liquid. Only the liquid isn't water, which would be frozen solid on Titan, where it's around 170 degrees below zero. Instead, the evidence is that it's liquid methane. Scientists even believe it rains methane regularly on this far-off moon, located a four billion kilometer journey through the Solar System from earth. Only it's methane rain.
And that's not all. There appears to be stuff like dirt on Titan, and large chunks that are similar to rocks. Scientists believe the sandy substance is in fact shards of crushed ice on Titan. The rock-like substances are larger chunks of ice.
Titan seems vastly different from our home planet, but European Space Agency mission manager Jean-Pierre Lebreton says he is struck by the similarities.
LEBRETON: "Our new picture of Titan is really fascinating. And what we are seeing is earth-like processes on Titan. But the big difference is the ingredients are somewhat different. The liquid on Titan is methane; the liquid on earth is water. The rocks on earth are silicate. The rocks on Titan are ice blocks. And the dirt on earth is our dirt. The dirt on Titan is organic matter."
BRYANT: Only a week after receiving date from the Huygens probe, the scientists findings are still preliminary. They say it will take weeks and months to sift through the rich trove of data sent by the space probe. And they say many mysteries remain.
The Titan landing is a joint project by European and American scientists. It took the Huygens probe seven years to reach the planet, traveling aboard the Saturn probe Cassini. And it took Huygens more than two hours to float down to Titan's surface, slowed down by parachutes.
Scientist Martin Tomasko says the probe seems to have settled in a dry corner of the planet -- similar to parts of Africa, or the United States.
TOMASKO: "The region we landed in is more typical of arid regions on the earth. We don't think we have open pools of liquid methane, but the methane kind of sinks down into the surface material, into the sand, if you will. It's more like Arizona, or a place like that, where the river beds are dry most of the time."
BRYANT: Because the probe landed on only one area of Titan, scientists have no idea whether it's representative of the entire moon, or whether there are more humid regions elsewhere.
The Titan findings mark a coup for the 15-country European Space Agency, which worked in collaboration with Americas NASA. The Europeans are also savoring an earlier success of a Mars mission, which produced photographs, which its scientists say offer the most direct evidence that water in the form of ice may exist on that planet. And scientists Friday suggested it might be possible to explore Titan in the future with a moving rover.
CHIMES: Also in Europe, Airbus this week unveiled the world's newest and biggest passenger jet, the A-380.
At an elaborate ceremony unveiling the plane, French President Jacques Chirac declared it a "technological feat," although in fact the difference between the A-380 and other recent jets is more its size, than revolutionary technology. The A-380's most obvious difference from other planes is the second, full-length passenger deck. The plane is 73 meters long, with a 79-meter wingspan and a 24-meter high tail. When it begins passenger service it will carry 555 people on non-stop trips one-third of the way around the world.
As scientists explore the human genome in an effort to better understand human health, they are getting insights from unexpected sources. As VOA's Rosanne Skirble reports, the newly-revealed genetic blueprint of the honeybee is pushing the field of comparative genomics in new directions.
SKIRBLE: When Kent Hackett talks about honeybees, he compares them in glowing terms to hard-working domestic farm animals. Mr. Hackett coordinates programs on bees and pollination for the U.S. Department of Agriculture Research Service. He says honeybees play a starring role on the farm.
HACKETT: "They pollinate ninety plus crops in the United States. In fact honeybees make eating fun. They pollinate the crops that make dinners delicious."
SKIRBLE: Such as almonds, blueberries and alfalfa.
HACKETT: "So we study bees in order to increase pollination of important crops that we love to eat as well as to control the different diseases that are setting bees back."
SKIRBLE: The laboratory in Beltsville, Maryland is among five USDA bee research facilities in the United States. From the window on the second story of the laboratory building, Jay Evans looks out over two dozen beehives - white wooden boxes that stand out against the facility's winter-idled fields. Two hundred colonies are scattered in seven other Beltsville field locations. In this season's suddenly cold temperatures, bees have gone into a slowed-down winter housekeeping mode.
But the humans studying them are very busy. Mr. Evans directs technicians as they pour over data to identify disease resistance traits in the honeybees. Jay Evans points to a long series of numbers or gene sequence represented on his computer screen.
EVANS: "What we have here is an alignment of a honeybee gene, an as-yet described gene, that has a strong match to a strong immune gene in a fruit fly."
SKIRBLE: This work in comparative genomics is relatively new. The honeybee genome project - supported by the USDA and the Human Genome Research Initiative - began in 2003. The completed sequence is one-tenth the length of the human genome and includes 15,000 genes. Entomologist Jay Evans is on a mission to explore connections with disease in honeybees.
EVANS: "Right now we are trying to find out which aspects of the immune response in bees are weak points -- they share an immune response with other organisms, such as ourselves -- which aspects of that response are weak points, are susceptible to failure when the bees are exposed to disease. And we can do that by connecting the genes in bees to known genes involved with this response in other organisms, and also by simple genetic experiments in the laboratory. Ultimately, it always gets back to a laboratory exercise, but we are narrowing the candidates involved with this trait down from perhaps thousands to ten or twenty genes."
SKIRBLE: Jay Evans hopes the results will translate into breeding more disease-resistant bees. It has also connected entomologists to a larger research community.
EVANS: "We are all studying some of the same disease pathways in bees, in cows, in humans, and using that we can all share information. We have collective databases. We're able to really speed up the research simply because we're all speaking a similar language and in many ways conducting the exact same experiments on our organisms of preference."
SKIRBLE: It might not be a coincidence of nature that the temperature inside a beehive is similar to that of the human body. Entomologist Jay Evans says as scientists look more closely at the genetics of the honeybee they are beginning to see more of themselves.
MUSIC: Flight of the Bumble Bee (Klazz Brothers & Cuba Percussion)
Honeybees, of course, produce honey, a sweetener that many people use in hot tea when they have a cold or flu.
Across the United States, a shortage of flu vaccine has prompted health officials to limit its distribution to people considered at highest risk for the contagious disease, formally known as influenza. The World Health Organization estimates the flu kills between a quarter-million and a half-million people worldwide each year.
Often, poor city residents don't have access to doctors or clinics where they could get their shots. But VOA's Adam Phillips reports on one group that is working to solve that problem -- by taking free flu vaccine right to people's homes.
PHILLIPS: It is ten in the morning in Spanish Harlem, a rambling Manhattan ghetto with such a large Latino population that the local McDonald's restaurant plays Puerto Rican music for its diners.
But the five Project Viva workers huddled at a corner table don't seem to notice the music. They are busy deciding which nearby apartment buildings they will visit this morning in their ongoing door-to-door campaign to give free flu shots to area residents.
GLIDDEN: "There has always been a disparity in health care services between the wealthy and parts of the community that are less affluent."
PHILLIPS: That's Kay Glidden, a research nurse with the New York Academy of Medicine, the non-profit organization that runs the Viva Project. She says the rationale behind the vaccination campaign is to head off a possible flu epidemic in communities already weakened by chronically inadequate health care:
GLIDDEN: "… We found in our study that several neighborhoods have very poor access to medical care and the rate of vaccination is very low among adults. Facilities are not available, transportation to get to the facilities isn't available, insurance is almost non-existent, or if they have families to take care of, they don't have a lot of free time to go looking for resources. So they go without."
PHILLIPS: Not everyone will accept the flu shots Project Viva is offering. Outside in the frigid air, while the team walks to its first destination, Jose Sanchez, one of Project Viva's interview outreach workers, and Sarah Sisco, the Project Director, explain why people living on the legal or economic fringes often turn health workers away at the door, or need coaxing before they agree to a flu shot.
SANCHEZ: You have a lot of 'wheeling and dealing' and goings-on with prostitution and stuff like that.
PHILLIPS: So people are suspicious.
SANCHEZ: Of course, of course. I would be. People coming to the door with yellow jacket? I would be.
SANCHEZ: You know, you get a knock on the door, [and] even if you see a friendly face, not everyone is going to say "Sure let me roll up my sleeve and let me inject you with something." So we've taken great pains to make sure that that legitimacy is conveyed from the first second that we knock on the door.
PHILLIPS: Outside an apartment on the third floor of a badly dilapidated tenement building, Mr. Sanchez explains why he thinks that undocumented immigrants seem to be most likely to agree to a flu shot.
SANCHEZ: "An immigrant is appreciative of the fact that we are coming to their door and with something that's never been done before and for free. And we don't ask anything of them. We don't ask their name. We don't ask for any money or anything. All we ask is to take the simple survey, five minutes, and you get the shot."
PHILLIPS: The anonymous survey is a key part of Project Viva. It asks people simple, essential questions -- whether they are working or not, how frequently they see a doctor, whether they have HIV/AIDS. Their answers are compiled by researchers at the New York Academy of Medicine into a database that helps the Academy target its public health outreach more effectively.
The man at the door, like most of his neighbors, agrees to take the survey and get a shot.
Outreach worker Jose Sanchez says the bottom line is that in poor neighborhoods like New York's Spanish Harlem, struggling families who might otherwise have gone without life-saving health care are getting it.
SANCHEZ: "So us [our] helping them can only be a good thing."
PHILLIPS: You smile when you say that.
SANCHEZ: Absolutely. Yesterday we did an 86-year-old man and he was happy to see us and that makes it worthwhile!
PHILLIPS: For Our World, this is Adam Phillips in New York.
If you're listening to Our World, chances are you're interested in space exploration. Whether it's the Huygens probe to Titan or the rovers on Mars or the International Space Station, it's hard to match the awe of discovery and the cutting-edge technology that is literally out of this world. To keep up with developments in space, you might want to surf over to our Website of the Week with an easy-to-remember name, Space.com.
DUIGNAN-CABRERA: "I think what we offer, what other sites can't offer, is a history of covering space. We work in collaboration with Space News, our sister publication, which is an aerospace industry newspaper, and the combined reporting staffs have a history of covering space of almost 50 years."
Anthony Duignan-Cabrera is the managing editor of Space.com. Much of the information on Space.com can be found on other websites, such as NASA.gov, but Mr. Duignan-Cabrera says his site goes beyond that.
DUIGNAN-CABRERA: "Well the NASA website's just going to tell you what they found. We're going to be able to go in with a little insight to say, well they found this, or they did such-a-thing, but remember they were working on this and that didn't work. So we're able to keep in mind the bigger picture and inform the reader of that."
One thing you immediately notice about Space.com is that the graphic design has a futuristic look, like you might see in a science fiction movie or TV show.
DUIGNAN-CABRERA: We think that space should be cool, and I think NASA I think actually has kind of followed our lead in recent years, and now their site is actually more interactive and a lot more streamlined and a lot cooler. And that's the strength of Space.com is that it fires the imagination by presenting space and related subjects in an imaginative way."
What I like about Space.com is that it goes beyond the headlines. You'll find information about the latest news of course, but there are also stories about feeding astronauts on the long flight to Mars; a space trivia quiz; a schedule of upcoming launches; even a section on SETI -- the search for extra-terrestrial intelligence. If you want to explore space from the comfort of your computer, surf on over to Space.com, or get the link from our site, voanews.com/ourworld.
Sixty-five million years ago, it's now widely believed, an asteroid slammed into earth, abruptly changing climatic conditions on the planet and leading to the extinction of much of Earth's life, including the dinosaurs.
An earlier, even bigger mass extinction -- this one 250 million years ago -- has also been blamed on a comet or asteroid, but now evidence is emerging that the cause may have been something familiar from today's headlines: global warming.
In some of the latest research, a group led by Professor Peter Ward of the University of Washington in Seattle studied both geological and fossil evidence. He says that evidence of the mass extinction 250 million years ago looks very different from the record left when the dinosaurs went extinct. Certain mineral evidence of an asteroid impact does not appear in 250-million year old rocks. The timetable was also very different. The earlier extinction, 250 million years ago, started with slow changes over millions of year, then speeded up.
WARD: "The highest rate of extinction seems to be occurring over of a period of about 10,000 years. Now, if you say 10,000 years to a geologist, they go, wow! That was fast! Well, that's about the amount of time it took to do this really nasty mass extinction. At the end of the Age of Dinosaurs, the extinction may have taken months, not 10,000 years."
So what sort of animal was it that went extinct 250 millions years ago? Well, all kinds, but the most noticeable would be what scientists technically classify as "pre-mammals."
WARD: "But were we to see them, I think we would recognize them as being mammals. They're probably hairy. They look very much like dogs or wolves or sheep. And there were a lot of them. They are the fauna that gets slaughtered. And what takes their place are dinosaurs. So we are seeing, really, an age of mammals at 250 million years ago that is stopped dead in its tracks, literally and figuratively by what I consider a global warming catastrophe."
Working in the Karoo Basin of South Africa, Professor Ward found no evidence of a comet or asteroid impact. What they did find, instead, was evidence that the climate was changing, including less oxygen and more carbon dioxide in the atmosphere.
WARD: "Instead of cars back then, there were enormous volcanic eruptions, but on a scale that would just be unprecedented today. These are big fissures in the Earth where liquid lava just pours out, and as it does so, enormous amounts of carbon dioxide go into the sky."
About one-third of Siberia, for example, is covered with lava from this period, suggesting the extent of these eruptions. The other source of CO2 resulted from a drop in sea level, which exposed sea sediment which released methane, a powerful greenhouse gas, and also reduced the amount of oxygen in the atmosphere.
Although policymakers and scientists debate the threat of global warming, atmospheric concentration of greenhouse gases such as carbon dioxide are increasing. Professor Ward says among the life forms most vulnerable to climate change are food crops, which have been bred for productivity, not necessarily survival in a changing climate.
WARD: "Global warming affects plants. The plants we care most about are our crops. We better damn be sure that we do not perturb crop yields."
Professor Peter Ward of the University of Washington. His paper was published this week in the online journal Science Express, and will be coming out soon in the print edition, Science.
That's our show for this week. If you've got a question about science, technology, health or the environment, we'd like to answer it. And we've got a VOA gift for you -- IF we use your question on the program.Email us at email@example.com. Ourworld is all one word. Or write us at -
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Our World is edited this week by Rob Sivak. Our technical director is Eva Nenicka. Jai Wallace is our assistant director this week. And this is Art Chimes, inviting you to join us online at voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology...in Our World.