This transcript is provided as a service; there may be some variation between it and the program as broadcast.
MUSIC: "Our World" theme
Straight ahead on "Our World" ... What is a planet? A proposed new definition ... The missing moon tapes ... and collecting plants in an age of high-tech botany ...
MYLES: "When you're collecting plants, it's a perfect record of the vegetation. So you can say 'this plant grew at this location at this time, and here is the plant.' That's good data!"
Those stories, post-traumatic stress disorder in Vietnam veterans, the International AIDS Conference, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
For several years now, there has been debate in the astronomy community over whether the ninth planet, Pluto, really is a planet. In many ways Pluto is an anomaly, a tiny body way out there past Jupiter and the other giants. And its orbit is tilted with respect to the flat plane of the rest of the Solar System. Then, scientists started discovering other similar bodies in the far reaches of our Solar System ? including at least one even larger than Pluto.
So what, exactly, is a planet?
The International Astronomical Union (IAU) set up a special committee on planet definition, including Prof. Richard Binzel of MIT. We reached him in Prague, where he explained the committee's proposed definition.
BINZEL: "The new definition of a planet is an object that is large enough and massive enough that its own gravity can pull it into a spherical shape. Period.
Q: That's it?
BINZEL: "It also has to be orbiting around a star."
Q: OK, so it's a general definition that would apply to our solar system and and any other as well.
BINZEL: "That's right. The goal of this definition is to apply not only to our solar system, but to other solary systems as well."
Q: Under this definition, does Pluto remain a planet.
BINZEL: "Yes Virginia, Pluto is a planet."
Q: Why is a new definition of a planet needed?
BINZEL: "The last decade has seen a revolution in our understanding of the solar system, particularly the far reaches of the solar system. We now know that out beyond Neptune ? in fact, out beyond Pluto ? is a zone of bodies, literally thousands of bodies out there that are basically like a third region to our solar system. And in that region we know that there are many Pluto-like objects remained to be discovered."
Q: And these are the plutons?
BINZEL: "These Pluto-like planets that are out beyond Neptune are now proposed to be called plutons, which just means they're Pluto-like planets."
It turns out that, under this draft definition, there would be a total of 12 planets ? the nine we've known since Pluto was discovered in 1930, plus the one that's officially called 2003 UB313 (but informally known as Xena), Ceres, and interestingly enough, Pluto's own moon, Charon.
The proposed new definition of a planet could upset traditionalists, with three new planets added immediately and the potential of many more in the years to come. But Binzel says the new definition is based solidly on science.
BINZEL: "In our committee we tried to find what were the most important fundamental principles that could be used to define a planet, and gravity and the ability of gravity to pull a body into a spherical shape seemed to be the most fundamental physical principle to decide whether or not something is a planet. ... This is a revolution in our understanding of the solar system in terms of understanding the complexity of our solar system, particularly the outer solar system, and this is not your father's solar system. This is a new view of the solar system that tells us there are now 12 planets, and there are sure to be more."
MIT Professor Richard Binzel, a member of the International Astronomical Union Planet Definition Committee, spoke with us from the IAU meeting in Prague. They'll vote on the proposed definition of a planet next week.
The U.S. space agency NASA this week conceded it has lost track of some of the original master tapes containing data from the Apollo lunar program, including the video of astronaut Neil Armstrong's first steps on the moon in 1969.
ARMSTRONG: "That's one small step for man one giant leap for mankind."
For technical reasons, the Apollo video was transmitted in black-and-white at 10-frames-per-second, much lower quality than broadcast television. NASA official Richard Nafzger said the actual images carried on live TV here in the U.S. and around the world were photographed by a television camera off a monitor.
NAFZGER: "What the American public saw was live TV of the first step on the moon, and it was pretty good, but nowhere near as good as we can do today with the digital technology we could use on the original tapes to convert it to broadcast TV."
NASA thinks the missing reels - they don't want to call them lost - the missing reels may be among a collection of as many as 13,000 Apollo tapes that they think may be located at the Goddard Space Flight Center. But Richard Nafzger says he's confident the tapes' whereabouts are documented ... assuming they can find the documents.
NAFZGER: "Again, I would reiterate that nothing happened. It's a matter of being able to take the time and logically go through the records of 37 years to find out where they are. It would be nice if we could put our finger on them without even thinking."
Officials will be stepping up the search for these priceless artifacts of an important moment in history. In the meantime, though, they seem a little embarrassed.
VOA health reporter Jessica Berman has been in Toronto this week, covering the Interantional AIDS Conference, and she's on the line with us now. Jessica, I guess the first question has to be, were there any big breakthroughs announced?
BERMAN: Well I think, Art, one of the most exciting developments to come out of the AIDS Conference here in Toronto has to do with a group of HIV-infected individuals, what they're calling 'elite controllers.' Now, these are people who are infected with HIV, who have very, very low levels of HIV in their system, who for whatever reason ? and this is the big mystery ? never actually become ill with the disease. And they estimate that about one in 300 individuals are with the situation. Now, at Harvard University, they're now recruiting a group of these so-called elite controllers to do a genetic study, to see if they can figure out why exactly it is so-called elite controllers never do become sick.
Q: And the hope is they'll be able to learn, perhaps, something that can help the other 299 out of 300?
Q: You know, for many people in wealthy countries, HIV/AIDS has become a serious but treatable condition. Of course that's not true in many other countries where medicines and treatments have not been available. The conference theme this year is Time to Deliver. What does that refer to.
BERMAN: You know, when this epidemic first started 25 years ago, there was a lot of optimism that a vaccine would be developed and a cure would be found and everything would be fine. Well, that hasn't really happened. And so this time around, conferees and people in the international AIDS community wanted to focus on something that's achievable. They want to turn the tide of HIV infection, and they want to do it with proven strategies, such as education, prevention, universal access to treatment, to care. Microbicides are something that, while we don't have or there is no microbicide at this point that works, it's something that conferees here believe is achievable in the short term, more accessible than a vaccine at this point.
Q: In terms of the role of women in preventing the spread of HIV ? and you talked about the microbicides ? what about the behavioral issue of women in relationships. Was that a subject of conversation at the conference?
BERMAN: It's constantly a subject of conversation at the conference, the role of women and men in relationships. And I think a big theme here at the conference ? actually the major theme ? is empowering women. So one of the themes of this conference was getting women to have more of a say and to take control of their lives and their bodies in a way that it can have an effect on stopping the spread of HIV.
Q: I guess you'd have to say the least-empowered people with HIV and people at risk are children. And the WHO's top AIDS official [Dr. Kevin De Cock] on Wednesday said that only about 10 percent of the children who need anti-retroviral drugs are getting them out of two million estimated children with HIV. What sort of attention did children get at this conference?
BERMAN: Well children are getting a fair amount of attention because, as you say, they really don't have much of a voice. And in many countries, children are orphaned because of HIV. Their parents have died, and getting access [to treatment] is, at best, a difficult thing, and if you're a small child and you don't have an advocate, you're even less likely to get that treatment, but at least attention is being paid here at the conference to that difficult situation.
Q: HIV/AIDS doesn't exist in a vacuum. There, obviously, are social and economic factors involved in many places. Behavioral issues. But also, other diseases are linked to HIV and AIDS, and we talked about this earlier before we went on the air: can you talk about the relationship between tuberculosis and HIV/AIDS.
BERMAN: Absolutely. About a third of people with HIV eventually become infected with tuberculosis. So there is a recognition here that you have to treat both HIV and tuberculosis at the same time as if it were the same problem. The other thing is, this conference talked about treating people prophylactically. In other words, giving them something before they get sick to prevent them from developing tuberculosis. What you would do is, you would treat people with HIV with an old standby tuberculosis drug called isoniazid. And it costs pennies for a treatment regemin, and a six-month course reduces the risk of tuberculosis in somebody who's infected with HIV by around 75 percent.
Q: That sure sounds like a cost-effective approach. VOA correspondent Jessica Berman at the International AIDS Conference in Toronto. Jessica, thanks very much.
BERMAN: My pleasure.
MUSIC - "Zero Patience" from the film Zero Patience: A Movie Musical About AIDS
And you're listening to VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.
America's Vietnam War ended more than 30 years ago. Of the millions of U.S. military veterans who served in the area, a significant number later developed symptoms of post-traumatic stress disorder, or PTSD.
Two large government studies published in 1988 came to very different - and controversial - conclusions about the extent of PTSD.
Now, a new study published this week in the journal Science and based on some of the same data, came to a conclusion somewhere between the earlier studies, finding that as of 1988 ? more than a decade after the war ended ? almost one out of 10 Vietnam veterans was suffering symptoms of PTSD, and that almost 20 percent had experienced it at some point.
The study was led by Dr. Bruce Dohrenwend of the New York State Psychiatric Institute, who said that, even more than the previous studies, he found a strong link between how horrible the troops' experience was, and the liklihood of having PTSD.
DOHRENWEND: "We showed probably an even stronger dose-response relationship - a very important finding because you know it's as near as you can come to a demonstration of a causal relationship in an observational study like this."
Symptoms of PTSD include nightmares and flashbacks. The Vietnam War may be ancient history for some, but Dohrenwend says his research still has resonance today.
DOHRENWEND: "Exposure to traumatic events aren't limited to the war zones. At least some of this is going to carry over to experiences with traumatic events in civilian life. But more directly and more probably of current note is that the Vietnam war is history, but the wars in Iraq and Afghanistan are not."
This study was based on data from the 1980s. A companion article by Harvard psychologist Richard McNally says increasing numbers of veterans have been seeking disability payments for PTSD in recent years. McNally points out that post-traumatic stress disorder among veterans of controversial wars is itself surrounded by "controversy," but he stresses the importance of having the best possible science as a basis for helping those victimized by PTSD.
Next, we head for the US-Canada border and Campobello Island, where decades ago President Franklin D. Roosevelt loved to visit. Today, it's a place where botanists study plant life. As in most all sciences, there is a lot of high technology involved in botany, but as we hear from VOA's Adam Phillips, there's no substitute for good, old-fashioned plant collection.
PHILLIPS: It is a clear, warm summer morning on Campobello Island, in the central Acadia Forest system, a vast tract of wilderness stretching nearly many hundreds of kilometers from New York State to Nova Scotia in Canada, and Peter Romkey is in his element. As director of the K.C. Irving Environmental Science Center at Canada's Acadia University, it is Romkey's job to oversee the students and others who will be collecting plants here, and then to compare those plants to the 300,000-plus specimens already in the university's collection, some of which date back to the 1850s.
ROMKEY: "And what you can do is you can look at the leaf size. You can look at the size of the plant. You can look at the stomata. In some instances you can sequence the material ? the DNA sequence of the plant that was collected in 1850, and compare it with the same plant found in the same area, in 2006."
PHILLIPS: Romkey says the study may help determine how the plants in the Acadia system are changing, due to global warming, for example.
ROMKEY: "What is it gonna look like a hundred years from now? Are we gonna have problems with one species over another? Are those species economically important to man, or are those species environmentally important to man? And that is this whole sense of this ecosystem and community study."
PHILLIPS: Any forest system is indeed a vast community of species. Nearby, Acadia University botany student Ben Myles stoops by a stand of Spirea alba or meadowsweet, a common low-lying plant with creamy white five-petaled flowers. He has his wooden pressed-specimen holder, with its blotting paper, its protective polyethylene sheets and its vice-like leather straps. Myles explains to an onlooker that he must make careful notes of the habitat in which the meadowsweet was found before cutting the specimen.
MYLES: "We are basically on the roadside right now, and the main forest is white spruce and larch. Then you'd also say associated species. So any of the shrubs that are growing along with it ? I'd mention those as well, the clover and stuff, underneath. You just want to give as much general information about where the plant is growing as you can."
ONLOOKER: "Do you always have to get it like this when it's in full bloom?"
MYLES: "It doesn't necessarily have to be. You want representatives. You want 'no flowers.' You want flowers in bud, flowers that are open. You want fruits. So here it is. You put it in its layer with the blotter paper on top of it. Then that cardboard, then you squish it all down, put the other piece of wood on top, and then strap her up. Usually we step on it to get it really squished. There we go! Then we've got our speciman. When you collect plants, it's a perfect record of the vegetation. So you can say 'this plant grew at this location at this time, and here is the plant.' That's good data!"
PHILLIPS: When it comes to nature, however, one cannot be complacent. Peter Romkey reminds us that, like the plants they contain, forests themselves are always evolving.
ROMKEY: "Generally speaking, when you get a dense thick forest like we're standing in, a few years ago, it would have been very shady here with just maybe a few needles and some mushrooms. And now the trees are starting to mature and individual trees are falling out. Like you can see a nice brightly lit hole beside us. And in there, the grasses and the mosses will come in first, when it lightens up a little. And you can actually see a little oak tree over there and a poplar tree. This is false holly. And these are shrubs that come in only when enough light is produced in a forest. This forest is in a state of transition."
PHILLIPS: Like all forests, the complexity of the relationship among species in the Acadia Forest is as daunting as it is beautiful, and there is widespread concerns over what humanity's effect on the climate has been and will be. Yet Peter Romkey remains hopeful.
ROMKEY: "We are the first organism in the history of the world that has the ability to change the way we do things ? to improve, conserve or preserve our environment. I am an eternal optimist. We've made some messes and we're fixing them up and we'll make more messes and we'll fix those up, but I think in the long run, I think we're gonna be okay!
PHILLIPS: On Campobello Island, on the U.S.-Canada border, I'm Adam Phillips reporting for Our World.
Time again for our Website of the Week, when we showcase interesting and innovative online destinations. This week we pick up our space theme again with a website that uses images from the Hubble Space Telescope in the service of science education.
EISENHAMER: "Amazing Space is designed to use the imagery and data from the Hubble Space Telescope to bring current science into [kindergarten to 12th grade] classrooms."
Bonnie Eisenhammer heads the formal education department at the Space Telescope Science Institute, creator of the Amazing Space website at amazing-space.stsci.edu. The site is designed for kids, high school age and younger, and includes a host of activities for learning about space, and science in general.
There's a lot to read on the site, but you can also learn using the cool interactive features on Amazing Space....
EISENHAMER: "Where you can actually use Hubble data and imagery in an interactive way. You can shoot a comet at Jupiter to see if you can hit or miss it using all the science concepts that you need to do that. So there's fun in interactive ways to engage in science."
Another feature you might enjoy is the monthly animated guide to the night sky.
TONIGHT'S SKY: "Stargazing on a hot August night reveals a multitude of wonders in the southern sky. The center of our Milky Way galaxy lies in the direction of the great constellation Sagittarius, the archer."
Amazing Space also has special resources for teachers who want to bring some of the latest, real-world science into their classroom.
EISENHAMER: "It's current science that, for educators, they'll never see in a textbook for quite a while, if it ever gets there. And it's a way to infuse the system with new thinking, new science that otherwise, they'd have to wait [for]."
The latest astronomy to help teachers and excite students at the Amazing Space website, amazing-space.stsci.edu, or get the link from our site, voanews.com/ourworld.
MUSIC: "Our World" theme
That's our show for this week. If you'd like to get in touch, email us at firstname.lastname@example.org. Or use our postal address -
Voice of America
Washington, DC 20237 USA.
Faith Lapidus is our editor this week. Eva Nenicka is our 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.