October 30, 2006 5:27
They're Saving the Hubble!
Two years ago, in the aftermath of the Columbia disaster, NASA officials decided to cancel a planned servicing mission for the Hubble Space Telescope. The idea had been to replace the space telescope's aging gyroscopes and to upgrade some of its instruments, prolonging the amazing orbiting eye's lifespan to 2011 at least, and making a telescope that's been stunning the world with dazzling images since the early 1990s even more powerful. But astronaut safety was suddenly in question, and completion of the scientifically useless but politically important International Space Station a priority. Canceling the repair mission would free up one shuttle shot, and because the Hubble is in a completely different orbit from the station, it would eliminate the one mission where astronauts couldn't possibly transfer to the station if things went wrong.
But after a sustained outcry from the astronomical community, the agency promised to revisit the cancellation. Tomorrow--that is, Tuesday, October 31--NASA is holding a press conference to announce whether or not the repair mission will go forward after all. Nobody's leaking the decision. Given NASA's understandable aversion to bad press, though, it's pretty clear that if the mission were off for good, the agency wouldn't be making a big splash about it; they'd issue a press release at 3 A.M on a Sunday, and hope nobody took notice.
In short, the Hubble is getting a new lease on life. That's me talking, but I can virtually guarantee NASA will confirm my announcement in the morning.
TUESDAY UPDATE
NASA Administrator Mike Griffin just announced that they're going ahead. The Hubble will be refurbished and repaired. There will still be a rescue option in case the astronauts discover, once in orbit, that the shuttle has a problem that would make re-entry dangerous: a second shuttle, on the pad and ready to go up and save them. Projected mission date: early 2008.
October 30, 2006 5:00
Is My Trunk Too Big?
JOCHEN LUEBKE / AFP / GETTY
A six week old African elephant
Most animals can't recognize themselves in a mirror; if they notice anything at all, they generally think it's another member of their species and might try to interact with it socially. Humans are different, of course; we know it's us in the looking glass, not another person. So do the great apes—chimps, gorillas and orangutans—and bottlenose dolphins.
And so, report animal behavior experts in the current Proceedings of the National Academy of Sciences, do elephants. Scientists at the Yerkes National Primate Research Center at Emory University exposed elephants at New York's Bronx Zoo to 8'x8' mirrors—bigger than in previous experiments—and the pachyderms responded with behavior of self-awareness, including touching marks painted on their foreheads that would otherwise be invisible, and examining their own mouths. It makes sense, say the scientists, that elephants would share this high level of self-awareness with other creatures that have complex social organization and a capacity for empathy—qualities elephants clearly have as well.
October 30, 2006 11:26
The Scary Economics of Global Warming
People who like to paint global warming as an overblown threat often point to the huge costs of trying to fix it. What if we spend billions or trillions to stave off a threat that isn't there? And even if the problem is real, argue iconoclasts like Bjorn Lomborg, the self-styled Skeptical Environmentalist, humanity faces more immediate troubles that demand more immediate spending.
But those arguments are false, says a new report out of the United Kingdom. Put together by economist Sir Nicholas Stern, the study pegs the likely economic hit from human-induced climate change at a whopping 20% reduction in global economic output over the next several decades, due to such things as massive droughts, hundreds of millions of refugees from rising sea level, the widespread extinction of species. That's comparable, says the report, to the devastation caused by the Great Depression, or one of the World Wars.
The good news, says Stern, is that this economic disaster, which he deems very probable based on a survey of scientific evidence, can be largely staved off with an investment of about 1% of the world's GDP in carbon-reduction and other schemes. The bad news is that we have to start pretty much right away. And while Tony Blair has hailed the new report and promised that the U.K. will take serious measures, there's pretty much no response out of the White House. Could he be miffed that Al Gore has signed on as an adviser on climate change to the British government? Maybe he wanted Gore's wisdom on this side of the Atlantic. On second thought.....nah.
October 25, 2006 5:15
Maybe Extinction is Sometimes a Good Thing
Early humans were walking around Africa 2 million years ago, but not South America, and thank goodness. Imagine having to run from a fast running, carnivorous, ten-foot-tall bird with a powerful, hooked beak--and presumably, a healthy appetite. Fossils of these enormous animals, known formally as phorusrhacids but informally--and understandably--as "terror birds," have been found before. But the skull dug from rocks in Patagonia, in Argentina, and announced in Nature today, comes from the biggest example ever found. It's the biggest bird of any kind ever known to have roamed the Earth, and according to Luis Chiappe, a paleontologist at the Natural History Museum of Los Angeles County, it bears structural details that overturn a long-held belief about these monsters: they did not, as previously thought, become more sluggish and slow-moving the bigger they got. Just as paleontologists revamped their views of dinosaurs like Tyrannosaurus rex a decade or two ago, deciding they were fast-moving predators, the terror birds were evidently quick as well. As if being huge, nasty and hungry weren't enough.
October 19, 2006 10:41
Invisibility: The Other Shoe Drops
You may see some stories in the next few hours or days about the development of an "Invisibility Cloak" by scientists at Duke University, based on research at Imperial College, London. You'll probably have to read well past the headline to learn that this was already news back in the spring. But if you're a regular reader of Eye on Science, you know that already.
Just as a reminder: if you make yourself invisible, light rays pass right through, or completely around you. That means no light is absorbed by your retinas. That means you're completely blind. Now, who wants to sign up?
October 17, 2006 10:02
Al Gore Got This One Right. Whew!
I liked Al Gore's movie "An Inconvenient Truth" a lot--but while it was mostly right on the money about the science of climate change, I had to cringe every so often as Gore said or implied a few things that were either not proven or not strictly true. One of those statements (or was it just an implication? I can't quite recall) was that the Larsen B Ice Shelf on the coast of Antarctica disintegrated in 2002 as a result of human-triggered warming. It's not that this was implausible; maybe it was true. But there was no real evidence for it, and as someone who feels that global warming is a serious issue, this bugged me. It provided ammunition for global-warming doubters to suggest Gore was nothing but a propagandist.
Today, though, a new study came out that retroactively gives Gore's assertions a scientific basis. A team of British and Dutch climate scientists, writing in the Journal of Climate, show that the ice-shelf collapse is very likely the result of stronger westerly winds blowing across the northern part of the Antarctic Peninsula. Those winds have strengthened in large part due to human-induced warming, say the authors, and also due to ozone hole over Antarctica, another human-caused phenomenon, .
So if Al is listening: you're off the hook on this one. And really, most of the film was very accurate, so don't worry too much.
October 13, 2006 10:02
Cool Asteroid Movie
NASA/JPL IMAGE COURTESEY OF DAN SCHEERES AND STEVE OSTRO
Frame from a movie showing a radar-derived computer model of near-Earth binary asteroid (66391) 1999 KW4. The larger component is about 1.5 kilometers in diameter and rotates once every 2.8 hours, and the components' orbital period is 17.4 hours
Back in 2001, the double asteroid known as KW4 passed within a couple of million miles of Earth--not nearly close enough to be a danger, but close enough that planetary scientists could bounce radar signals off the two mutually orbiting objects that make up the system. The result, presented in the online journal Science Express, is a series of incredibly detailed images of a couple of truly bizarre objects. The larger of the two, known as Alpha, is about a mile across, and spins once every 2.8 hours. The smaller object, Beta, is about a third as big, and denser, and orbits Alpha once every 17 or so hours.
What's surprising here is that Alpha is spinning fast enough to make its equator bulge way out--which wouldn't be possible if it were really a solid chunk of rock. Instead, it's clearly more of a "rubble pile" of smaller rocks held together--but just barely--by their mutual gravity.
This is important information because sooner or later a near-earth asteroid is going to crash into us (it won't be this one, though). If we get enough advance warning, we can try and do something about it. But one popular idea--detonating a huge bomb right next to the asteroid to knock it into a different orbit--might not work in this case. Instead, it could simply knock the asteroid apart, leaving most of the pieces on the same orbit as before--so we'd get multiple big impacts instead of one huge one. Oops.
Oh, and I did mention a movie. Here it is.
October 12, 2006 4:32
Multiple-Personality Planet
When it comes to getting publicity, planet-hunters are victims of their own success. All told, they've found more than 200 alien worlds orbiting distant stars over the past decade. That's great if you want to understand the range of possible solar systems and to know how likely it is we'll ever find a twin of Earth--but pretty bad if you want headlines.
Every so often, though, scientists make a discovery that's hard to ignore. Last month it was the fluffiest planet ever found. And just an hour or so ago, astronomers at a meeting of the American Astronomical
Society's Division for Planetary Sciences that they'd used the Spitzer Space Telescope to measure day and night temperatures on a planet orbiting the star Upsilon Andromedae, about 40 light-years from Earth.
It's the first time such a thing has been done; Spitzer did it by measuring the infrared light coming out of the system as the planet whipped around its parent star. Depending on where in the cycle the astronomers looked, they'd see just the star (as the planet ducked behind), the star plus the planet's night side, or the star plus the planet's day side. They had to be quick: this planet, like many of the extrasolar planets found so far, has a "year" that lasts less than five days. That means it's very close to Upsilon Andromedae, so it's no surprise that the day side is incredibly hot.
What is a surprise is that the difference between the day and night sides is extreme--2,550 degrees Fahrenheit. Because it's so close to the star, the planet is very likely to be tidally locked, always showing the same face to U. Andromedae, just as the Moon always shows one face to the Earth. Even so, you might expect that the atmosphere of the presumably mostly gaseous planet would circulate, carrying heat to the night side. The fact that this isn't happening suggests that the atmosphere somehow re-radiates energy at a prodigious rate--and why that might be is still a mystery.
October 11, 2006 2:01
Perils of an Unstable Earth
In its most oversimplified formulation, the process that drives evolution--that is, natural selection--is known as "survival of the fittest." Organisms with some inborn advantage in staying alive and healthy will reproduce more than their competitors, and have more offspring with that same inborn advantage...and so on through the generations.
What constitutes "fittest," though, doesn't always stay the same. Dinosaurs were so extraordinarily fit that they dominated the earth for hundreds of millions of years. Then something drastic happened to change the environment . The most widely accepted candidate is an asteroid or comet strike from space; the resulting planet-wide dust cloud shut out the sun, plunging the relatively warm planet into a deep freeze and dooming the heat-loving reptiles. One day, the dinosaurs were fittest. The next day, they weren't, and small, furry, heat-retaining mammals were.
There have been a handful of mass extinctions on a par, or even greater, than the one that doomed the dinosaurs, but also a lot of much milder events that paved the way for a burst of evolutionary adaptation. And a new report in Nature suggests a mechanism for one puzzling feature of the fossil record. Mammalian species survive, on average, about 2.5 million years, suggesting some recurring planetwide phenomenon with that spacing.
According to a team of European scientists, the phenomenon is most likely a cyclic change in the shape of the Earth's orbit around the sun, in which our planet's slightly elliptical orbit becomes closest to being a perfect circle. For complex reasons, that tends to trigger a planet-wide cooling and expansion of ice sheets--an environmental change that renders previously ideally adapted species less fit than more cold-tolerant species.
October 6, 2006 5:45
Meet Me at Victoria Crater
We haven't heard much news from Mars lately, but that's only because the two most important missions exploring the red planet have been getting themselves into position for some spectacular imagery--and it all came together today, as NASA presented extraordinary pictures from on the ground and from orbit of Victoria Crater.
The ground photos come from the Opportunity rover, which has taken nearly ten months to wheel over to the half-mile wide crater, the remnant of an ancient impact, on Meridiani Planum near the equator of Mars. That's pretty impressive, given that Opportunity was only desinged to operate for 90 days; it landed in January, 2004, which means it's closing in on three years of operation. Despite some aging parts, mission scientists plan to drive it right down into the crater, to study ancient rock layers exposed in the crater walls--far deeper layers than anything yet seen.
At the same time, though the Mars Reconnaissance Orbiter, which has been nudging itself into the right orbit since last March, has finally taken some of its first, unprecendentely high-resolution images from about 180 miles straight up. They're so stunningly clear, in fact, that you can see the five-foot-high Opportunity, its shadow, and its tracks, leading up to the crater. Over the next few years, the Orbiter will cover the entire planet, creating an extraordinary map of the Red planet that can be used for study and for planning future exploration.
I can't wait.
October 6, 2006 10:55
This Just In!
October 6, 2006 10:06
Good Grammar on the Moon
I may be the last to weigh in on this story, but at least I'm the most skeptical. Last week, the Houston Chronicle reported on a new analysis of Neil Armstrong's first words as he became the first human to step onto the moon. What Armstrong insists he said was "That's one small step for a man, one giant leap for mankind." But if you listen to the tape, the first "a" isn't there: it goes "That's one small step for man, one giant leap for mankind."
Unfortunately, this renders the sentence pretty much meaningless, since "man" and "mankind" mean the same thing in this context. Armstrong and NASA have always argued that history books should report what he meant, not what he said--which is more than a little Orwellian. Of course, any or all of the great utterances reported in history books might be entirely made up. Maybe Caesar didn't say "Et tu, Brute." Maybe he said "Damn, that hurts a whole lot." We don't have an actual recording, so we have to go with what might be completely apocryphal.
We do have Armstrong's recording. But according to the Chronicle, a computer programmer from Australia has found the missing "a" on it. Using a program that helps the handicapped use nerve impulses to activate a computerized voice, Peter Shann Ford claims he's shown that it's there on the tape, but only lasts 35 milliseconds, ten times too fast to be audible. Armstrong's comment, as reported by the Chronicle: "'I have reviewed the data and Peter Ford's analysis of it and I find the technology interesting and useful,' Armstrong said in a statement. 'I also find his conclusion persuasive. Persuasive is the appropriate word."
It sure is. Armstrong has been persuaded that the thing he's claimed for 40 years to be true is true. Think that took a lot of persuading? I don't, really. I also don't quite see how a person can speak a word ten times too fast for it to be audible. And I especially don't see how you can extract that information from a tape as scratchy as this one was. Don't take my word for it: listen.
Nobody seems to have asked Mr. Ford these questions. Nor did anyone, evidently, question why he wrote up his findings "in the format of a scientific paper" rather than writing an actual scientific paper and submitting it to an actual scientific journal, where it could be critiqued by actual scientists. But that's probably because this was a NASA-sponsored event. The agency is even better at spin than it is at space exploration, and this is a great example.
October 5, 2006 2:45
Aztec Discovery
The Zocalo in Mexico City is a huge, paved square at the center of the nation's traffic-clogged, smoggy capital, surrounded by government palaces and other official buildings...and, just a few yards away, improbably the partly excavated remains of a structure that stood when the Conquistadors arrived some five centuries ago. The Templo Mayor was the site of bloody sacrifice by the Aztecs who once ruled here...and now, say archaeologists, the most important Aztec discovery in decades. It's an altar carved with images of Aztec deities and a huge stone slab that may mark the entrance to an underground chamber that contains...well, that's the interesting part. Nobody knows--but Mexican archaeologists will be given all the time they need to find out.
October 3, 2006 9:46
Nobel Soap Opera
I was surprised to learn this morning that the Nobel Prize in Physics has just been awarded to John Mather and George Smoot for their discoveries back in the early 1990s about the Cosmic Microwave Background radiation (CMB) left over from the Big Bang--not because their work was anything less than extraordinary, but because they were barely on speaking terms a decade ago.
Some background: the CMB radiation was first detected in the mid-1960s by Arno Penzias and Robert Wilson, of Bell Labs, and even though they found it by accident, they got Nobels for the initial discovery. The reason: if the universe really did start in a super-dense, super-hot state billions of years ago, there should be faint remnants of its light whispering through the universe. By finding it, these two astronomers turned the Big Bang from merely a plausible theory into a very powerful model of cosmic origin.
What Mather, of NASA's Goddard Space Flight Center and Smoot, of the University of California, Berkeley, did was to run experiments on a satellite that firmed up the initial discovery enormously. Mather's experiment on COBE, the Cosmic Background Explorer satellite, showed that this ancient light had exactly properties you'd expect from a cooling cloud of once-hot gas, thus ruling out alternate explanations that had dogged the theory. Smoot's, meanwhile, showed that the radiation had hot and cold spots across the sky, reflecting places where the original cloud had been slightly more or slightly less dense than average--differences that led to the huge clusters of galaxies and big empty voids that characterize the modern universe.
So far so good. What surprised me was that these two men will presumably have to say nice things about each other for the next few months, at least. Back in 1992, when Smoot's results were announced, Mather and other members of the COBE team were furious with Smoot for what they described as a totally unethical grab for glory. Indeed, Mather wrote about it in the book he co-authored with John Boslough, titled The Very First Light. A couple of quotes, referring in part to a press release issued prematurely by Smoot's home institution:
"COBE team members were nonplussed, disagreeing about what to do about George's repeated violations of the team's publication policy. His actions were an extremely serious matter in the minds of many team members..... Ray Weiss [chairman of the COBE science teak] told Chuck Bennett [Smoot's deputy]...that he thought George should be removed from the project." According to Mather's book, Weiss asked Bennett if he wanted the job. Bennett evidently refused, on the grounds that it would reflect badly on the project as a whole. (My own interviews with Bennett, Smoot and Mather on these questions appear in my book, Echo of the Big Bang, published in 2003; they confirm this story).
So while you may be reading plenty about this year's physics Nobels, now you know--with apologies to Paul Harvey--the rest of the story.
About Eye On Science
TIME contributing writer Michael D. Lemonick fills you in on what's hot, what's cool, what's controversial and what's just plain silly in the world of science. Comments encouraged.
RSS Feed
 |
Daily Email
Recent Posts
Eye On Science Archives
July 2008
Choose a day to view events.
<< Previous Months
| 1 | 2 | 3 | 4 | 5 | ||
| 6 | 7 | 8 | 9 | 10 | 11 | 12 |
| 13 | 14 | 15 | 16 | 17 | 18 | 19 |
| 20 | 21 | 22 | 23 | 24 | 25 | 26 |
| 27 | 28 | 29 | 30 | 31 |