"Our World" theme
week on "Our World" ... Making gasoline out of plants ... New
findings about lighting up those so-called "light" cigarettes ... and
if clothes make the man, as they say, then feathers make the bird ...
SAFRAN: "When we manipulate a male's color to
look darker, he does better, he attracts more mates. And he has more offspring.
This is the currency of evolution. Having a number of babies."
bird's eye view of the mating game, plus falling snow ... on Mars, and more. I'm
Art Chimes. Welcome to VOA's science and technology magazine, "Our
part failure delays shuttle repair mission
have a pile of space news this week, so let's start with that.
Monday, NASA disclosed a problem on the earth-orbiting Hubble Space Telescope.
A piece of onboard equipment has failed, preventing the telescope from sending
scientific data back to Earth.
manager Preston Burch told reporters in a teleconference that technicians have
been working on the problem —
BURCH: "And all the testing and all the
efforts so far to restore it have indicated that it has totally failed."
a lot of space hardware, this device, the Science Data Formatter, has some
built-in redundancy. And NASA will switch to its backup circuits over the
coming days. But the backup has been in space for almost two decades, and if it
fails, the Hubble telescope will be useless.
now, the plan is to have astronauts replace the Science Data Formatter when
they do other repairs and upgrades on a shuttle mission that was scheduled for
mid-October. Because it will take some time to get the replacement Science Data
Formatter tested and ready, the shuttle repair mission will be delayed ...
probably until mid-February at the earliest.
this seems like a setback for Hubble, NASA official Ed Weiler said it's a good
thing the Hubble failure happened before the space shuttle repair mission.
WEILER: "Think about if this failure had
occurred two weeks after the servicing mission. We had just put two
brand-new instruments in and thought we extended the life for 5-10 years and
this thing failed after the last shuttle mission to Hubble. So in some sense,
if this had to happen, it couldn't have happened at a better time."
lander sees snow falling on Mars
Mars next, where NASA's Phoenix lander has been finding various indications of
ice on the Martian surface. And Jim Whiteway, the lead scientist for Phoenix's
weather instruments, says they've now detected falling snow.
WHITEWAY: "The ice crystals would be starting out
at about a height of about four kilometers.
And by the end of the measurement, in this case, they have fallen all
the way down to about to two-and-a-half kilometers ... So that is snow is falling from the clouds
and we are going to be watching very closely over the next month for evidence
that snow is actually landing on the surface."
told reporters that apparently the snow they saw vaporized before reaching the
surface of Mars.
discovery was based on data sent back by one of the space probe's instruments
called lidar, which works something like radar except it uses laser light
rather than radio waves.
pretty active week for NASA, which on Wednesday celebrated its 50th
as they say on TV commercials — but wait, there's more...
readies spacecraft for Mercury fly-by
Monday a U.S. space probe will fly past Mercury in one of a series of close
encounters with the closest planet to the Sun.
flybys are really navigational moves aimed at getting the Messenger spacecraft
into orbit around Mercury in 2011. But as it swoops just 200 kilometers from
the surface of Mercury, the spacecraft's instruments will race to capture
pictures and other information about the solar system's smallest planet. VOA's
Jessica Berman has details.
BERMAN: Monday's rendezvous with Mercury is the
second of three flybys by Messenger, which stands for Mercury Surface, Space
Environment, Geochemistry and Ranging.
which was launched in 2004, is using the encounters as critical gravity assists
to help ease the spacecraft into Mercury's orbit in 2011.
flyby will bring Messenger very close to the planet's surface, according to
Daniel O'Shaughnessy, head of guidance and control of the mission.
O'SHAUGHNESSY: "Messenger will whiz 200 kilometers
above the planet. During this time,
Messenger will train its suite of miniaturized instruments at portions of the
planet never before seen at such a distance."
BERMAN: NASA scientists say there will be a
seventeen minute black out, during which time Messenger's instruments are
expected to capture some 1,200 images of Mercury's rocky surface.
officials say the second Messenger encounter with Mercury will follow up data
gathered during Messenger's January flyby, during which scientists learned new
details about an enormous impact crater, volcanic structures, and lava fields.
Solomon is the mission's principal investigator.
ACT: "What we're expecting is to
see additional examples of the kind of geological features, the kinds of
geological units characterized by colors and shapes that we've seen so
BERMAN: Mission managers say Messenger's second
swing-by of Mercury will reveal 30 percent of the planet. Between Messenger's January rendezvous and
images sent back by the Mariner missions 33 years ago, space scientists say
they will soon glimpse 95 percent of Mercury's
space probe will fly past Mercury one more time in September 2009 before
settling into permanent orbit in three years. Jessica Berman, VOA News,
advancing on 'green' gasoline from plants
probably have heard about ethanol and biodiesel, liquid fuels made from plants
rather than petroleum. They use a renewable resource, and burning them doesn't
contribute to global warming.
can be blended with gasoline and run in an unmodified vehicle, but add enough
ethanol to the mix and you need to make changes to the engine.
why can't you make gasoline directly from plants? Well, it turns out that you
can. At least that's what some promising research programs suggest, according
to William Schultz of the National Science Foundation and the University of
SCHULTZ: "What we are going to do is change a
biofuel, such as poplar, switchgrass, corn stover (which is just the part of
the corn we don't normally eat) and others, and by one of three processes —
gasification, pyrolysis, or deconstruction — produce precursors to green
"precursors" are chemical molecules similar to what is found in crude
oil, molecules that can be refined to produce gasoline.
mentioned that there are at least three different ways to get from plants to
gasoline. Gasification is the oldest, and has been used to convert coal to
gasoline, but it is expensive and not very efficient.
uses heat and chemical catalysts to promote the conversion of plants to
gasoline. It is efficient and can even use waste paper as its raw material, but
so far can only produce some components of gas.
third process uses sugars, which can be easily derived from plants. It is being
developed at a company called Virent Energy Systems. Company founder Randy
Cortright says their process produces gasoline that's actually better than what
you can buy at a service station.
CORTRIGHT: "We did an analysis of this, of our
green gasoline versus just standard unleaded gasoline we got at the gasoline
station across the street. We have the same components in there. In fact, it's
actually got a higher octane and some preferable blending component that you
says Virent's plant-based process can also produce chemicals that can be used
to make plastics and pharmaceuticals, just like petroleum. It can also produce
jet fuel, noting that ethanol is a poor choice for aviation fuel since a liter
of ethanol packs less energy than a liter of gas.
CORTRIGHT: "You don't have the energy content
there. While you can burn ethanol in your automobile, you would not take
ethanol and put it on an airplane because it has a lower energy content. And
ideal fuel right now is a hydrocarbon fuel, and what we're looking at is, the
hydrocarbon doesn't have to come from petroleum. It can come from biomass, and
that's what we're doing with our process."
its briefing on green gasoline, the National Science Foundation decorated a
meeting room with some of the plants that might fuel the 21st century energy
HUBER: "If you look at some of these plants
around here, what we're trying to do is take the non-edible portion of the
plants. This is the fastest [growing] and most abundant form of plant material,
and produce green gasoline, green diesel, and green jet fuel.
of Massachusetts chemical engineering professor George Huber pointed out that
it's not enough just to turn plant biomass into gasoline, you have to do it
efficiently and economically to compete with petroleum.
HUBER: "Making a fuel — it's a commodity. You
have to have a very highly optimized and integrated process to make a profit.
You're competing against petroleum oil that's been around for over 100 years,
and the petroleum industry has developed and they've learned how to
economically refine crude oil. Now we need to learn how to economically refine
gasoline made from crude oil, burning green gasoline produces carbon dioxide, a
greenhouse gas. But there's virtually no net impact on climate because the CO2
released is the same CO2 absorbed from the atmosphere when the plant was growing.
research on green gasoline is still ongoing, William Schultz of the National
Science Foundation pointed out that it is building on technologies that have
been around for a long time.
SCHULTZ: "So it's not a technology that's 20 years away. I
think we think it's 5-10 years away."
Schultz points out that while the chemical process for making green gasoline
still has a long way to go, so does the breeding of plants specifically
designed to be turned into fuel. Breeding has improved wheat, corn, and other
crops over thousands of years. Improvements can also be expected in the
undomesticated plants that would go into biofuels.
industrial facilities may one day be making gasoline, jet fuel, and maybe even
plastics and medicines from plants. And smaller facilities might end up right
where biomass is grown.
SCHULTZ: "Even a farm that produces primarily
food crops, just its waste product might be enough to produce more energy than
they need. Perhaps you could do enough energy from the waste products from the
food production that you could make a farm energy-self sufficient, even if it's
not a biofeedstock energy producer."
Schultz of the National Science Foundation, which hosted the seminar on green
even in light cigarettes, affects brain
has been declining in many industrialized countries in recent decades. But the
global picture is different, with the number of smokers on the rise.
this has come an increase in the number of people suffering from heart and lung
diseases, and cancers. Many people would like to quit, but it's very difficult
— in part because tobacco is extremely addictive. Some people try to quit by
switching to low-nicotine, or 'light' cigarettes. But as we hear from health
reporter Rose Hoban, that's not very effective.
HOBAN: Researcher Arthur Brody, with the University
of California at Los Angeles, says the primary addictive substance in tobacco
is nicotine. It's only one of thousands
of chemicals in tobacco smoke. But when a person lights up, nicotine floods
chemical receptors in the brain.
BRODY: "Nicotine occupies these receptors and
desensitizes them so essentially turns them off. And so, for some reason, this results in all of the reasons that
people smoke, you know the pleasure that they feel, or the reduced anxiety or
the little boost in their mood sometimes.
HOBAN: One strategy people use to quit smoking is
to use low-nicotine cigarettes. Brody
recently studied these co-called light cigarettes and their effects on smokers'
brains. First, he had people smoke
regular cigarettes while they were in a brain scanner. He could track how many nicotine receptors
in the brain were affected.
BRODY: "If they only took one or two puffs of
the cigarette, that occupied 50 percent of this type of nicotine receptor in
the brain. Whereas if they smoked a
full cigarette, it occupies about 88 percent of those receptors."
HOBAN: Then Brody gave people so-called
low-nicotine cigarettes ...
BRODY: "… which have even less nicotine than
light cigarettes. Even those little-nicotine cigarettes occupied 77 percent of
these receptors. And so the majority of
these receptors get occupied very easily with very small amounts of nicotine in
HOBAN: Brody found that even with cigarettes that
are supposedly 'de-nicotinized,' about a quarter of the nicotine receptors in
smokers' brains were occupied.
BRODY: "The problem is that sometimes people
buy a light cigarette and they inhale them more deeply, or they smoke more of
them, and so there really is no benefit if they do them that way."
HOBAN: Brody says these findings mean that many
smokers who think they're weaning themselves off tobacco by smoking so-called
'light' or low nicotine cigarettes might not actually be getting any benefit
from them. He says that people using
these light cigarettes to quit need to be careful about how much they smoke, or
they may need to use a method that reduces the amount of nicotine they
receive in a more reliable way, such as
by using nicotine patches.
research is published in the International Journal of
Neuropsychopharmacology. I'm Rose Hoban.
distributions on our Website of the Week
again for our Website of the Week, when we showcase interesting and innovative
time, it's a guide to the wide range of software packages known as Linux
distributions - the free alternatives to Microsoft Windows or Apple's Mac OS
that also include a vast array of professional quality application programs for
your desktop computer.
BODNAR: "DistroWatch is a website, it's a
portal, it's a news and reference site about Linux distributions."
Bodnar is the founder of DistroWatch.com, perhaps the Web's most complete
survey of the different flavors of Linux available out there. Linux
distributions are built on the same reliable core but each one adds different
bells and whistles — some distros (as they're known) are for general home,
school, or business use. Others specialize: there are editions for Linux
newbies and computer security experts; Christians and Muslims ; language
versions in Vietnamese and Bulgarian and Farsi, among others; even minimalist
versions for old and slow computers. But most users will be interested in the
mainstream offerings on the Major Distributions page.
BODNAR: "This lists the 10 most popular Linux
distributions with screen shots and little descriptions that tell you what it
is and what it's best for. That can help somebody new to Linux decide how to
choose their distribution."
one of the great things about Linux is that many distributions come in the form
of a live CD, which boots up on your computer without affecting anything on
your hard drive, so you can do a no-risk test.
Bodnar says DistroWatch gets more than 100,000 visitors a day. Others keep up
with the Linux world by subscribing to the various RSS news feeds or by
listening to the podcast.
PODCAST: "Hello and welcome to this week's
episode of the DistroWatch weekly podcast. In this week's episode, the Linux
package management cheat sheet, part two, new warnings over the e1000e network
and information about the vast array of Linux distributions at DistroWatch.com,
or get the link to this and more than 200 other Websites of the Week from our
MUSIC: Lionel Hampton — "Lullaby of
VOA's science and technology magazine, Our World. I'm Art Chimes in
up birds increases appeal to mates
finally today ...
know, in a lot of ways, what goes on in human society is a lot like what
happens in the animal kingdom.
we look for a mate, we often are attracted by external features — smooth skin,
perhaps, or a certain hair style or body type.
one reason why clothes and cosmetics are such big business. Now, a team of
scientists in the foothills of the Rocky Mountains have in effect done cosmetic
surgery on a bird called the barn swallow and as a result improved its mating
success. Shelley Schlender reports.
SCHLENDER: Barn swallows fly into a horse barn near
Boulder, Colorado, carrying insects for their hatchlings, who wait in nests
made from pellets of mud. With their swooping flight and dark blue plumage,
swallows are elegant birds. The males are especially striking, thanks to long
tail streamers and a brownish orange chest. But according to biologist Rebecca
Safran, those average looks won't guarantee a mate.
SAFRAN: "Females really have the upper hand in
the mating game. Males are kind of a dime a dozen, and females are really
holding their cards close to their chest."
SCHLENDER: To find out how much appearance appeals to
the lady birds, Safran and her research team captured male barn swallows. Using
colored markers, they darkened the orange chest feathers on some of them. They
also collected a tiny drop of blood to identify each male's DNA and track his
hormone levels. In addition, they got DNA from baby swallows. In this way, they
discovered that the males whose chest feathers had been enhanced fathered more
SAFRAN: "When we manipulate a male's color to
look darker, he does better, he attracts more mates. He has more offspring.
This is the currency of evolution. Having a number of babies."
SCHLENDER: Those males also had higher levels of the
male sex hormone, testosterone.
SAFRAN: "The surprising finding is that simply
by changing the male's appearance, his physiology also changed."
SCHLENDER: The darker orange chest feathers seem to
attract more females. Safran and her students speculate that these successful
interactions may be what raise the birds' testosterone levels. She says that
her study is the first to document that changing the outward appearance of an
animal can change its inner chemistry.
assistant Connor Fitzhugh says the need to attract a mate is a big reason for
the dramatic tail feathers on male peacocks, and a lion's magnificent mane —
especially when it's a darker orange.
FITZHUGH: "This whole notion that the clothes
make the man, it's repeated throughout the animal kingdom. It's not unique to
SCHLENDER: In the wild, those looks are often a sign of
fitness, since only a male in good health can produce strong antlers, furry
ruffs, or extra colorful feathers.
team member, PhD candidate Matt Wilkins, says that when females like what they
see, they're probably judging with some accuracy a male's ability to father
babies, feed them and defend the roost.
"So, it makes sense. It's kind of an honest signal of quality in a good
SCHLENDER: Wilkins adds that the signal varies
depending on the male's environment.
WILKINS: "In North America, the males who have
more young have darker feathers. That's in comparison to in Europe where the
males on average are lighter and have longer tail stringers because there,
females don't care so much about the breast color but they prefer males with
longer streamers, so that's driving the difference in the species across the
SCHLENDER: Those differences might be caused by subtle
variations that determine swallow health in Europe and North America. It's an
example, according to Rebecca Safran, of how species change over time. And her
research is showing how much female choices about male looks can be part of the
SAFRAN: "What we believe is happening is that
we're able to record evolution in action. That is, we're studying the formation
of new species as they're evolving."
SCHLENDER: But while the researchers have learned a
great deal by enhancing the feather color of male barn swallows, they don't
recommend this subterfuge as a successful path of evolution. While their
doctored males did father more young, they also lost weight, and this may
indicate they had to work too hard in order to keep up with their new
appearance. After all, unlike a male with naturally darker orange feathers,
these counterfeits didn't get their better looks because they were actually
healthier. In a horse barn near Boulder, Colorado,
I'm Shelley Schlender.
Safran's research on barn swallows was published earlier this year in the
journal Current Biology. And
thanks to the University of Colorado at Boulder for providing audio and video
material for this segment.
"Our World" theme
our show for this week. If you'd like to get in touch, email us at
email@example.com. Or use the postal address —
Voice of America
Washington, DC 20237 USA
Sivak edited the show. Eva Nenicka and Bob Doughty are the technical directors.
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.