MUSIC: "Our World" theme
Straight ahead on "Our World" ... NASA's latest steps toward a return to the Moon... America's threatened bird species ... and heartbreak and your heart:
GLASSMAN: "After heart attack, depression increases the risk that you'll die [by] 350 percent. It is as strong a risk factor as the strongest single medical risk factor."
Those stories, worrying about black holes, a year-end guide to some hot consumer electronics, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
On Wednesday, NASA announced the award of the last major contract for the Ares I rocket, part of the next-generation system that will carry humans into space after the shuttle fleet is retired in a few years.
The Ares rocket and the Orion crew capsule that it will blast into space are part of the U.S. space agency's Constellation program aimed at sending astronauts back to the Moon and then to Mars.
The target date for a moon landing is 2020, almost 50 years since the last Apollo astronauts visited the moon.
Although the general outlines of the mission are shaping up, NASA still hasn't decided whether the Orion spacecraft will return to an ocean spashdown, as American spacecraft did in the 1960s and '70s, or end their mission on dry land, as the Soviets have done.
"The simple answer is, we have not picked a landing mode for the Orion yet. Both options are still on the table."
NASA Associate Administrator Rick Gilbrech told reporters there are plusses and minuses in both approaches. Constellation program manager Jeff Hanley says the first test flights will land in water until they are confident that the guidance system is sufficiently reliable and accurate for a pinpoint landing.
HANLEY: "If you're going to land on land eventually, you want to be able to have proven the guidance system fairly robustly, because the consequences of landing short [of your target] in the Western United States ? in other words, landing in the mountains or landing on San Francisco ? the consequences are pretty grim."
As that suggests, flying to the Moon, let alone Mars, is something that NASA plans to do step-by-step, including flights to the International Space Station some five years before attempting to land on the Moon.
NASA is taking an incremental approach to human space exploration ? much as it did in the 1960s, first with the Mercury, then Gemini, and then Apollo manned spaceflight programs ? starting now with the International Space Station, the ISS, but moving more slowly because NASA today lacks the Cold War-fueled budget of the Apollo era.
HANLEY: "If you look at that whole program, from Mercury on through the Apollo program, it was an incremental buildup in capability. That's exactly what we're doing here. ISS is our Mercury for going to Mars. Lunar outpost is our Gemini. And of course, going to Mars is the ultimate Apollo for this generation. The challenge is how to do it on budgets that Apollo didn't have to deal with."
As it plans to send humans to the Moon, NASA isn't forgetting robotic exploration. The Lunar Reconnaissance Orbiter is set to launch in about a year to study and measure the Moon from orbit. Riding on the same rocket will be another unmanned mission called LCROSS, or Lunar Crater Observation and Sensing Satellite. The two-ton upper stage of the rocket it arrived on will crash into a crater near the moon's south pole, and the LCROSS satellite will fly through the material that is ejected, studying the lunar soil and looking for signs of water.
MUSIC: Ray Brown, Monty Alexander & Russell Malone ? "Fly Me to the Moon"
Time again to reach into the Our World mailbag to answer a listener science question.
We have an email from Uchenna Ezeani in Jos City, in Nigeria who wants to know about black holes. Specifically he's wondering about the possibility of a black hole destroying Earth.
As if we didn't have enough things to worry about.
Well anyway, to help us learn more about black holes we have James Trefil, a physics professor at George Mason University in Fairfax, Virginia.
Thanks for joining us today, professor.
TREFIL: "My pleasure."
Q: Before we get to the destruction of our planet, let's back up a bit. What is a black hole?
TREFIL: "Right now you're sitting on the Earth, and the entire Earth is pulling you down. That's the force of gravity, and that's what gives you weight. Now, if you imagine taking the whole Earth and just shrinking it to half its size, keep the same amount of mass but shrink it to half its size and make it more compact, that force of gravity will go up by a factor of four. And you keep shrinking it, the force of gravity keeps going up.
"Right now if you threw a ball up, the force of gravity would make it fall back down to the Earth, unless you threw it at 7 miles a second, that's 10 kilometers a second. If you threw that fast ? that's called escape velocity ? it would get away from the planet.
"Now as you shrink the Earth, that escape velocity keeps going up and keeps going up and keeps going up, and when you get down ? actually, for the Earth it would have to be something almost microscopic in size ? but cram everything into that size, then nothing gets out. And this is an object that we call a black hole. And what that means is that everything that falls into it through the force of gravity but nothing can get out, and by definition if something absorbs all the light that falls on it, it's black, which is where the name comes from."
Q: Well, it seems, then, if they are black, if the light can't escape they would be difficult to detect.
TREFIL: "They are. In fact they were first predicted just a few years after Einstein published a general theory of relativity. I think they were predicted in 1919, and it wasn't until the '70s that people really began to get evidence that they actually existed. We know of a couple of different kinds.
"For example at the center of the Milky Way, our own galaxy, there's a black hole that has a mass of about a million suns. It's a big thing; we can't see directly, but what we see is stuff falling into it. The stuff falls in, it collides, emits x-rays, it gets very hot, and we can detect that. And it looks like most galaxies have these kind of black holes at their centers.
"The other way you get black holes ? and these are the ones that usually come into science fiction ? is if you get very big stars getting near the end of their life, they explode what's called a supernova, and the remnant that's left behind can be a black hole."
Q: So, what is the event horizon?
TREFIL: "When you get to the event horizon, which is ? you think of it as the boundary of the black hole ? once you're inside that, you never get out. And that's what it is."
Q: If the black holes are swallowing everything around them, they must have swallowed up planets as these stars collapse?
TREFIL: "Well, not necessarily. Think of the solar system. The sun sits at the center, and it exerts this big gravitational force. The planets go in orbits and they don't fall into the sun. And if you're outside the event horizon, a black hole is just something that exerts a force of gravity, so what falls in is dust and small bits of debris that kind of clogs up and heats up and gives us x-rays, which we can detect."
Q: Is there a way of predicting, to get back to our listener's question, is there a way of predicting what will happen in our solar system with our sun?
TREFIL: "Well, our sun will not become a black hole; it's much too small. It will become what's called a white dwarf."
Q: Do black holes stay where they are? Is there the possibility of a traveling black hole?
TREFIL: "Well yeah, I assume this is what your letter writer had in mind. And the idea would be that if there is one out there ? of course we can't see it, so we wouldn't know ? is there one out there with our name on it? Well, I guess I'd answer the question this way: if you make your list of things to worry about and this is at the top, you're pretty good shape."
Q: If we have a black hole that's floating around in space; and it's sort of in our neighborhood but not really close enough to suck us in, what effect would that have on earth?
TREFIL: "Well, if it got inside the Solar System, it could mess up the orbits of the planets. It would be like having another star around [in our solar system]. If it's farther out you might be able to detect it because the black hole would bend light; the positions of stars would look like they were changing. It would be like looking through water or something at the stellar background. So I suspect if it was that close, you would know it was there."
Q. In any event the probability is quite small?
TREFIL: "As I said, if this is all you've got to worry about, you're in very good shape."
Q: Professor James Trefil of George Mason University. He's the author of a lot of books including his latest, "Why Science?" about the need for scientific literacy. Thanks for much for joining us.
TREFIL: "Thank you."
We'll be sending a special VOA gift to listener Uchenna Ezeani in Nigeria for asking us about black holes. If you've got a science question, please send it in. If we use it on the air we'll have a gift for you, too. Email it to email@example.com, or listen for our postal address at the end of the show.
Time again for our Website of the Week, when we showcase interesting and innovative online destinations.
Some of our favorite websites belong to America's great museums, and this week we invite you along on a virtual visit to Chicago's famed natural history museum.
MEYER: "The Field Museum website at fieldmuseum.org is a website that introduces the public to not only our current, past, upcoming exhibitions, but also introduces the world to our renown research and collections."
Allyson Meyer is web manager of FieldMuseum.org, which features some 27,000 pages dealing with everything from butterflies to the sounds of traditional musical instruments, or, in their newest exhibit, the history of maps.
The Field Museum is also a research institution, and the website opens a window on the work of the scientists out on expeditions.
MEYER: "So when a scientist goes in the field to do research, you can follow their day-to-day progress as they make new discoveries, and you can see it on the fly through photos [and] video. We've done an occasional few live, even, webcasts."
One of the museum's icons is its famous Tyrannosaurus Rex dinosaur skeleton, named Sue. According to the museum, it's the world's largest, most complete and best-preserved T. rex.
MEYER: "There's a great, in-depth look at the history of Sue, where she was found, all her connections around the world. You can go online and there's an interactive that tells you about what other things ? plants, fossils ? were found with Sue when she was discovered. But the website also gives you a deep understanding of why she's so important and what's unique about her."
Now, seeing the skeleton of a seven-ton dinosaur online certainly isn't the same as seeing it in person. But if you visit on your computer there are puzzles and games and other interactive features, and of course you can do it from home, school or your nearest Internet cafe.
Our Website of the Week is FieldMuseum.org, or get the link from our site, voanews.com/ourworld.
MUSIC: T. Rex ? "Get It On (Bang A Gong)"
It's VOA's carefully-curated science and technology magazine, Our World. I'm Art Chimes in Washington.
Twenty-five percent of all bird species in the United States are at risk of extinction, according to a report by the National Audubon Society and the American Bird Conservancy, the nation's leading bird conservation groups. As VOA's Rosanne Skirble reports, WatchList 2007 focuses on America's most imperiled birds in an effort to prevent their permanent disappearance.
SKIRBLE: These are the calls of birds in trouble:
WatchList 2007 names 178 of the most endangered birds in the United States. Audubon President John Flicker blames their decline on human activities.
FLICKER: "They are at risk from local habitat loss and from broader regional, national and global problems such as invasive species, unchecked development, sprawl, urban expansion and now in particular global warming."
SKIRBLE: Commercial fishing lines, wetland loss and offshore oil exploration threaten seabirds. American Bird Conservancy president George Fenwick says damage to breeding islands can rapidly wipe out a species.
FENWICK: "So if you have introduced alien mammals such as rats on a bird breeding island you can wipe out a population of hundreds of thousands of seabirds in a matter of a couple of years. And this has happened again and again and again, and because these seabirds are out of sight [and thus] out of mind, they don't get the attention that they deserve."
SKIRBLE: Nor do birds from Hawaii, Fenwick says. America's Pacific island state harbors 39 WatchList species in need of immediate conservation help. He says their fate is tied to just about every bad thing that can happen to birds including loss of habitat, invasive species, and avian malaria.
Some of the birds on WatchList 2007 overlap with those under the federal-administered Endangered Species List, which require requires government protection. The listing has saved birds threatened with extinction like the American bald eagle and the peregrine falcon.
But few species have been added in recent years. Audubon bird conservation director says Greg Butcher says WatchList 2007 helps to prioritize the needs.
FENWICK: "Above all the problems of these species and the habitats they share with us demand commitment, conservation plans to address their specific problems and the funding to make action happen."
SKIRBLE: Birdwatching, or birding engages between 40 and 60 million Americans. John Flicker with the National Audubon Society says tapping that constituency, as Audubon has done with its network of state and local chapters, can have an enormous impact.
FLICKER: "California residents spoke up loudly about lead shot recently, which caused the legislature and Governor Schwarzenegger to ban lead in the environment for producting the [California] condor. It was an historic act and that was a direct result of a public outcry and demand for, 'we've taken lead out of everything else, it's time to take it out of the environment."
BUTCHER: "I think that those political actions are actually tremendously important, and I think being political active is very empowering for people."
SKIRBLE: Audubon's Greg Butcher says people can start with personal action, such as by making their own backyard a healthier habitat for birds.
BUTCHER: "Pull out invasive weeds. Plant some of the native plants that are really important for the habitats there. I think if people can adopt local spots and we can encourage people to do that across the country and also encourage people to do that across the globe, it really is the case where people can act locally and affect the entire globe for bird populations."
SKIRBLE: Butcher says the fate of birds is closely tied to our own. He says their decline is a call to action to protect the species and the environment we share before it's too late. I'm Rosanne Skirble.
The lover who dies of a broken heart is a common fixture of the arts. But can hearts really be broken ? medically? ? by sadness or depression? Health reporter Rose Hoban has the answer.
HOBAN: Research over the last several decades is starting to prove that they can. There is a link between depression and subsequent heart disease, says doctor Alexander Glassman, a professor of psychiatry at Columbia University's College of Physicians and Surgeons. Glassman and others have followed heart attack patients who are depressed and gotten similar findings in these new studies.
GLASSMAN: "After heart attack, depression increases the risk that you'll die [by] 350 percent, three and a half-fold. It is as strong a risk factor as the strongest single medical risk factor."
HOBAN: Glassman led a panel to discuss depression and heart disease at this week's annual meeting of the American College of Neuropsychopharmacology. He and other scientists presented their ideas about how depression contributes to mortality. He says some reasons are obvious and have been known for some time.
GLASSMAN: "Depressed people don't listen to what their doctor says, they don't take their advice, they don't take their medicines. We can actually prove that. More depressed people were less likely to take their pills regularly."
HOBAN: But other ideas are new. For example, Glassman explains that immune reactions involving cytokines might damage the heart.
GLASSMAN: "Cytokines are agents in the body that mobilize an immune response to intruders, to bacteria, to viruses, to fungus and to foreign bodies. And depressed people have an increase in these cytokines."
HOBAN: Glassman says there are other new avenues of research that could pinpoint the relationships between depression and heart disease in the future. For now, he says, doctors need to take depression in their cardiac patients seriously and treat the problem aggressively. He also says family and friends of depressed patients should get more involved in their treatment, such as by making sure they take their medications and get to their doctors regularly. Because broken hearts can be mended. I'm Rose Hoban.
We're deep into the Christmas shopping season in America, with consumers doing battle at stores and online, looking for the best gifts at the best price. As he does every year at this time, VOA's Adam Phillips braved the crowds to find out what's hot in technology this year.
PHILLIPS: That's the sound of a game being showcased on the HP MediaSmart, the object of much consumer craving here at a Manhattan Best Buy, a national electronics chain that is doing brisk business this season. With its meter-and-a-half-wide screen, MediaSmart looks like a flat-panel television set. But as N'Gai Croal general technology editor for Newsweek Magazine put it, gaming and television are only two things this $2,300 baby can do.
CROAL: "It's essentially it's a PC computer inside of a television set to make it smarter. The idea is you can control all of your network media. So if you have movies stored on a laptop, and you have music stored on a desktop, as long as it's on your home network, you'd be able to access all of that from your TV through the remote so that you could watch it."
PHILLIPS: Croal says the HP MediaSmart is an example of so-called "agglomeration" in today's electronics design. That's where devices like TVs, music players and personal computers ? once bought and operated separately ? are combined into one unit. The aim, says Croal, is ease of use.
CROAL: "Absolutely. I mean, the trend towards accomparation makes it much easier for people toeaily access their control. I sort of look at this stuff and say 'is this something my mom could use?' And this is definitely something my mom could use! That's when I start looking at them a little more seriously."
PHILLIPS: Anyone's mom would enjoy the new Kodak EasyShare. It's a high-resolution digital camera small enough to fit into a hand purse, yet capable of snapping digital photos good enough to display on large, high definition TVs.
CROAL: It's currently being sold here for $279. And if you think back to the cameras they were selling two or three years ago, you wouldn't have all those features. It shows how people are finding ways to deliver more incredible features in the same size package for less money."
PHILLIPS: Interactive computer games are big again this year. Nintendo's Wii series is so popular that Best Buy has only a display model for buyers to ogle. It features a handheld device that sends a signal to the "virtual" you on the game screen that mirrors your movements. Already a big seller in Japan, Nintendo will soon introduce "WiiFit" to the American market. Croal says it's actually good for you.
CROAL: "And it comes with this thing that looks like a scale that you would step on to measure your weight. And it's a balance board and it can sort of measure shifts in position and weight. And they were going to use that essentially for workout activities ? for yoga, for push-ups, for sit-ups and for balance activities. And they sort of integrate it into the play."
PHILLIPS: But for Croal ? and hundreds of thousands of others, to judge from the sales ? the best new game is Rock Band by Electronic Arts. The kit allows you to put together a virtual band, play in it, and tour while learning to play lead and bass guitar, drums and sing superstar vocals.
CROAL: In order to get highest score possible, in order to get the most fans and unlock the various cities that you can tour, you really do have to play together. You have to pay attention to what your band mates are doing; you have to help each other out if one of you is not doing so well. And if you are doing well, you want to do well together.
Q: These other people you are cooperating with...?
CROAL: "They can be in your living room, right next to you, or they could be online. So it's a lot of fun.
PHILLIPS: It's a tough job, but someone's got to do it! N'Gui Croal is technology editor at Newsweek Magazine in New York. And at Best Buy Electronics in New York, this is Adam Phillips reporting for Our World.
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That's our show for this week. If you'd like to get in touch, email us at firstname.lastname@example.org. Or use the postal address ?
Voice of America
Washington, DC 20237 USA
Rob Sivak edited the program. Eva Nenicka is the technical director. 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.