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MUSIC: Our World theme
Straight ahead on "Our World" ... Planning for a comet rendezvous, a high court ruling on sharing MP3s and videos over the Internet, and research on how sleep can help your memory ...
WALKER: "Evolution has created sleep for a very specific reason. We have to start to learn that we can't shortchange either our brain and our bodies of sleep. Because there are consequences."
Those stories, a space shuttle update, and more... I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
The U.S. Space Agency NASA has given the go-ahead to launch the space shuttle on July 13th, a week from Wednesday. The decision by NASA managers was announced this week after a two-day Flight Readiness Review.
This will be the first shuttle flight since February 2003, when the shuttle Columbia broke up as it was re-entering the Earth's atmosphere, with the loss of the shuttle orbiter and the deaths of all seven astronauts on board.
Since then, NASA has been working at improving the safety of the shuttle program, with special emphasis on the cause of the Columbia accident -- debris that broke off the shuttle assembly at launch, damaging a wing. But on Thursday, Associate NASA administrator Bill Readdy said safety improvements were not limited to that problem.
READDY: "We said, immediately after the accident, that we would find out what happened and we would fix it, and we would return to flying safely again. The scope of work was not limited to eliminating the proximate cause of the accident. We went literally from stem to stern on the[shuttle] vehicle, throughout ground processing and management of the program to make sure that we did come back smarter and stronger and safer as a result."
The decision to launch comes despite the conclusion of an independent panel that NASA has failed to meet three key safety requirements. NASA chief Michael Griffin was asked about that when he appeared before the House of Representatives Science Committee on Tuesday. VOA's David McAlary reports.
McALARY: A commission of independent aviation experts NASA asked to assess the safety upgrades says the agency has fallen short on some of them, but in general has made the three remaining shuttles safe enough to fly again. The commissioners praised the work NASA has done to advance shuttle safety and Mr. Griffin echoes that view.
GRIFFIN: "I believe I have acquired a pretty good picture of where we are with respect to the technical requirements to return to flight. I've been tremendously impressed with the work that the team has done executing those improvements. The flight readiness review for the next couple of days will either uncover exception to that statement or will endorse it."
McALARY: When shuttle flights resume, they will continue the process of building the International Space Station, which the United States operates with Russia with support from Europe, Canada, and Japan.
But a legal constraint could interfere with U.S. participation in the project. A five-year-old U.S. law forbids NASA to pay the Russian space agency for station services unless Washington confirms that Moscow has not provided Iran with missile or weapons technology in the previous year. This has not been much of a problem so far, but under current plans, the United States will rely on Russia for emergency escape transportation back to Earth for its crew members once the station is completed. The law would bar that service and, in effect, prohibit U.S. activities on the outpost except when a shuttle is docked there.
NASA administrator Griffin says this situation is a major reason why he wants to replace the aging shuttle fleet by 2010 with a more agile astronaut craft that will allow the United States to maintain its independence in space.
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Comets have long intrigued astronomers and lay people alike. Although bright comets may be beautiful objects that delight observers, they have also been thought of as "omens," presaging disaster. As recently as 1910, gas masks were sold to people who feared they would become ill when the Earth passed through the tail of Halley's Comet. Today, astronomers want to learn more about the composition of comets, which are thought to contain ice, rocks, iron and other materials. The University of Maryland has joined the U.S. space agency NASA in an extraordinary experiment in which a spacecraft will actually slam into a comet. A nearby spacecraft, plus amateur and professional astronomers here on Earth, are expected to observe the results of the Deep Impact mission. Keming Kuo wrote our report, which is read by Barbara Klein.
TEXT: The comet impact mission was suggested by two University of Maryland astronomers, Michael A'Hearn and Lucy McFadden, coinciding with the release of Deep Impact, a 1998 science fiction movie about a comet on a collision course with Earth. Professors A'Hearn and McFadden used the film name for their proposal, and in January, seven years later, NASA launched two spacecraft on a six-month, 430-million kilometer journey to meet with comet Tempel One on July 4. That's when the comet will be at the closest point to the sun in its orbit. As University of Maryland astronomer Lucy McFadden notes, it will require great precision.
McFADDEN: "It's a first-of-a-kind mission where we are actually doing an experiment in space, a controlled experiment in space, [like] hitting a bullet with a bullet, and watching it with a third bullet. Once they realize what the mission is, it's exciting."
TEXT: A day before impact, the spacecraft separates into two parts. The smaller section, called the impactor, will actually collide with the comet, as the other section, the flyby spacecraft, uses special cameras to observe the collision from about 500 kilometers away as it flies past at 37,000 kilometers per hour.
Many earthbound viewers will be watching when Deep Impact collides with comet Temple One. Elizabeth Warner, University of Maryland observatory director and liaison to amateur astronomers for Deep Impact, says the mission is turning astronomers - who normally just observe the skies - into active experimenters.
WARNER: "It's a really cool mission because we're actually going to be affecting an object out in space. Up until now, pretty much everything we've learned about space is by observing; [astronomy is] a very passive field. You can't learn everything just by looking, so it's going to be very neat to be able to affect something and be able to see its insides a little bit to learn more stuff."
TEXT: The "stuff" researchers hope to analyze includes data from the impact crater, expected to be the size of a football field - about 100 meters in diameter: its shape, depth, size, particles expelled, and chemical reactions. Ms. Warner says it's not unusual for comets and other celestial objects to collide in space, but it is rare to get a good look at such an impact.
WARNER: "We are basically recreating a naturally-occurring event that happens in the solar system. The only difference is, is that, rather than having two unknowns - two comets hitting each other or an asteroid and comet where we don't know enough about either one - we know what the impactor is made of. So we've reduced that much of the equation and anything that does happen, we can kind of attribute to the comet."
TEXT: Ms. Warner says when the impactor probe hits the comet, there probably will not be a dramatic "flash." But it will brighten to a so-called "magnitude 6" object - or roughly the same brightness as the faintest star visible by the naked eye in a rural, dark setting.
WARNER: "The comet is actually a dim comet. One of the things that makes it very good for our mission is that it doesn't have a lot of dust being shed off of it. And so that makes it safe for the spacecraft so that we can fly closer, get better pictures and such. However, that makes it very boring for most amateur astronomers because we rely on the reflected light off of the dust particles for us to be able to see it from here on Earth."
TEXT: The unique nature of this space experiment means that many telescopes - both on Earth and in space - will be focused on the comet July 4 (or July 3, depending on where you are on Earth), as astronomer Lucy McFadden explains:
McFADDEN: "My colleagues will be at virtually every telescope they can get to: all the Great [space-based] Observatories - Chandra, Spitzer, and Hubble - will also be observing. And amateurs will be observing, and they're observing now. It's another thing: the Deep Impact mission is happening now; we are observing every day. We feel as if we're moving at 23,000 miles [37,000 kilometers] per hour."
TEXT: Lucy McFadden is one of the top scientists on the Deep Impact mission. Her colleague Elizabeth Warner says Comet Tempel One is one of millions of space objects - "just another dirty, little snowball" - but one that happens to be in the right place at the right time.
It's time again for Our World's website of the week, and this time we highlight a fascinating online program created by a New York artist who provides a unique and challenging way of way of looking at the top news stories of the day.
HARRIS: "It is a program that automatically selects the top 100 words and pictures in the world every hour, based on what's happening in the news, and then it takes those 100 words and pictures and displays them in a very simple 10-by-10 grid of photographs with the words off to the side."
Jonathan Harris is the artist behind Ten By Ten-dot-org, which takes its name from that array of photographs representing the hour's top news stories.
Every 60 minutes, Ten By Ten captures news from three top online providers [Reuters, the New York Times, and the BBC], and then parses the content.
HARRIS: "And looking at those articles every hour, it analyzes the word usage in those articles. And based on the word usage, it extracts the top 100 most meaningful words, based on some algorithms that hour in the news. And then, for each of those 100 words, it finds a picture from one of the news articles at those three sources. And then it associates the word with the picture and saves it into the 10-by-10 system."
The result is a grid of 100 thumbnail photos, each associated with a word which displays off to the side. Click on the picture, and you get a list of related stories. Often, the same picture shows up repeatedly in a ten-by-ten grid -- a feature that Jonathan Harris says many people incorrectly consider a bug.
HARRIS: "What it signifies are the very important stories. So if you see a picture that's being repeated ten times, you can be sure that that's a very important picture this hour, becuase the words that are associated with that picture are very important words this hour. So the result of that is that, in a way, you get this visual barometer of importance -- sort of like you do with a traditional newspaper when you look at the size of a headline."
Johnathan Harris is also the creator of WordCount.org, another fascinating site based on word usage. His Ten By Ten website was a recent Webby Award winner, beating out industry-leading search site Google in the 'best navigation' category. Catch the news in visual form at TenByTen.org, or get the link from our site, VOANews.com/ourworld.
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Your're listening to VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.
Since at least 1946, computers have been referred to as "electronic brains." And why not? They have memory, inputs and outputs, and if they don't have imagination, they certainly can do work that seems suspiciously close to what the human brain can accomplish.
But scientists at Cornell University in New York state are offering new evidence to suggest that it's not such a good analogy after all.
Participants in a series of experiments were shown pictures of two objects on a computer screen and asked to point to one of them, using a computer mouse. In some cases the names of the two objects were very different, like candle and jacket. But other times, lead researcher Michael Spivey says the mouse movement reflected how the brain parsed the request when asked to point to one of two similar-sounding objects, like candle and candy.
SPIVEY: "And so part way through hearing it, your brain's already starting to do some partial computation on that partial input, so your hand movement actually moves a little bit toward the candle when told, 'click the candy,' because your brain's sort of partly thinking that's what it's hearing."
When the objects sound similar, the mouse follows a more indirect path to the correct image, reflecting the brain's processing of the command.
At their most basic, digital computers are a collection of on-off switches. You can think of the brain's neurons in sort-of the same way, but Dr. Spivey explains that the brain's processing is actually more analog than digital.
SPIVEY: "You can see that these various modules of the brain that share information actually share it quite continuously. So part way through hearing a word, not only is the language doing some partial comptutations about the many words this word could turn out to be, but it's also continuously sharing that information with the motor system."
Cornell University's Michael Spivey. His research was published this week in the Proceedings of the National Academy of Sciences.
Another bit of brain research published this week sheds new light on the relationship between sleep and the ability of the brain to form memories.
In an experiment conducted by researchers at Boston's Beth Israel Deaconess Medical Center and Harvard Medical School, participants practiced tapping out a sequence of numbers on a special keyboard. It's similar to the kind of memory skill a pianist might need to learn a piece of music. After 12 hours they were tested on how well they remembered the number sequence. In some cases they got to sleep during that 12-hour period; in other cases they were awake.
Piano students may be told that "practice makes perfect," but lead researcher Matthew Walker says practice is only part of the story.
WALKER: "And what we found is that after you learn a memory task, you improve initially when you practice that memory task, but the brain doesn't stop learning, it turns out. Once you finish practice, the brain actually continues to learn in the absence of any further continued practice. However, that delayed learning, as it were, develops exclusively during sleep, and not during equivalent time periods when you're awake."
In the second stage, when they were trying to reproduce the finger movements they had memorized, the participants' brains were scanned using an MRI to see what parts of the brain were involved. It turns out that different parts of the brain were active, depending on whether they had slept during that 12-hour period between learning and testing.
During sleep, the brain apparently conducts what Dr. Walker calls "off-line memory processing" -- in this case reorganizing the motor-skill memory for more efficient retrieval the next day.
Dr. Walker says this research is only the latest in a series of studies that has led scientists to the understanding that the brain is quite busy during sleep.
WALKER: "We are starting to abandon the notion in science that the sleeping brain is simply a dormant brain. It turns out to be quite the contrary. In fact, parts of the brain can be up to 20-30 percent more active during certain kinds of sleep than when we're awake."
And Dr. Walker says his research adds to an ample body of research pointing to the importance of getting a good night's sleep.
WALKER: "It's certainly additional evidence to suggest that sleep is critical -- firstly in terms of our memory. From a more general perspective, though, I think it again just stresses that sleep is a biological necessity. Evolution has created sleep for a very specific reason, in fact probably for multiple reasons, and we have to start to learn that we can't shortchange either our brain [or] our bodies of sleep. Because there are consequences."
University students are famous for their poor sleep habits, and Dr. Walker says that includes the ones in his classes, despite their lessons about the importance of getting a good night's sleep. So I had to ask him about his own sleep habits.
WALKER: "[Laughs] That's a good question. Well the irony of sleep research, in fact, is that I get very little of what I'm trying to study. But in some ways it's actually a great, subjective insight into the consequences of sleep deprivation. So I actually see it as an academic endeavor and a benefit rather than a hindrance.
Prof. Matthew Walker of Harvard Medical School. His study on sleep and memory was published this week in the journal Neuroscience.
Finally this week, the United States Supreme Court unanimously ruled this past Monday that so-called "peer-to-peer" file-sharing computer networks can be held legally responsible when they promote the distribution of copyrighted materials.
The case involved a lawsuit by MGM -- the Hollywood and music industry giant -- against Grokster and StreamCast, two much smaller companies whose networks were used to distribute movies and other unauthorized, copyrighted material.
Although some of those files might have been public domain or otherwise legal to share, Grokster and similar peer-to-peer systems were in fact widely known as places to exchange feature films, music MP3s and other copyrighted materials without authorization or payment.
The Supreme Court decision highlighted the sharp division between those who want to restrict technology that can be used for both legal and illegal purposes, and those who focus on the benefits of those kinds of technologies.
On VOA's "Talk to America" call-in show Wednesday, guests on both sides of the issue explored the future of digital distribution technologies.
James DeLong, senior fellow at the Progress and Freedom Foundation, says content creators, such as the music and film industries, accept digital technology, and are working on restricting illegal copying while allowing authorized digital distribution.
DE LONG: "They certainly know the future is in digital distribution, and they certainly have every intention of profiting off it and of facilitating it. But I think technology does indeed advance, but so does rights-management technology, and I think people are certainly devoting tremendous effort to figuring out how you can set that up so that people can control the access."
But Wendy Seltzer, a lawyer with the Electronic Frontier Foundation, says the Supreme Court decision, which focused on the intent of a peer-to-peer network company, is likely to stifle innovation.
SELTZER: "The uncertainty is for companies making technolgy that can be used with copyrighted material. Because this legal standard is not clear -- the Supreme Court hasn't given us a bright line; it's instead said [that] if you intend your product to be used to infringe, you can be held liable -- and so it makes it difficult for technology companies to develop products where they don't know what the users are going to do with it."
The issues decided in the Grokster case will probably surface again. The conflict between technology that can be used both to infringe copyright material and copy other material goes back decades. In the 1970s a movie studio sued Sony over its then-new Betamax home video recorder. When the case was finally decided by the Supreme Court in 1984, the ruling favored Sony, saying the company was not liable, even if some of its products were used for copyright infringing purposes.
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That's our show for this week. We're always delighted to hear from you. Tell us what you like about the program, or what you don't like. Email us at ourworld@voanews.com. Ourworld is all one word. Or the postal address is -
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Voice of America
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Our World is edited this week by Rob Sivak. Our technical director is Gary Spizler. 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.