Tales of SCIENCE!

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  • edited December 2007
    An Asteroid Hurtles Toward Mars
    Astronomers have good news, better news and some bad news about an asteroid known as 2007 WD5. The good news is that this 164-ft.-wide chunk of speeding space rock, discovered in November in an ongoing search for potential threats to Earth, won't hit our planet any time in the foreseeable future. The better news — for eager space-watchers — is that the asteroid, currently about halfway between Earth and Mars, has a plausible chance of hitting the Red Planet at the end of January. If it does, astronomers will be treated to an unprecedented sight.

    The event itself, however, will have plenty of precedent. The craters that pock the surface of Mars, the Moon, Mercury and other Solar System bodies come from about four billion years' worth of this sort of thing. Earth has had plenty of collisions too; it's just that erosion, continental drift and vegetation have erased or hidden most of them. Not all, though: Meteor Crater, in Arizona, was blasted out some 50,000 years ago by an asteroid about the same size as 2007 WD5. A much bigger object, a few miles across, is thought by many scientists to be the reason the dinosaurs died out some 65 million years ago.

    If 2007 WD5 does smack into Mars, every telescope on Earth will be pointed in that direction — just as they were in 1994 when Comet Shoemaker-Levy 9 crashed into Jupiter. In that case, the comet broke up while it was still in orbit, so astronomers watched nearly two dozen individual impacts. But Jupiter is made mostly of thick clouds, so there was no lasting scar, and because it lies so far from Earth, the event wasn't quite as spectacular as this one promises to be. Asteroid 2007 WD5 should release some 3 megatons of energy if it slams into solid ground near Mars' equator, and orbiting satellites will show the aftermath with crystal clarity.

    Finally, the bad news: 2007 WD5 has only a 1-in-75 chance of actually hitting Mars, which means astronomers would be wise to be pessimistic. But the possibility of impact calls to mind a loosely related incident that occurred almost exactly 100 years ago, when something exploded above the Tunguska region of Siberia, flattening trees in a 25-mile radius, their trunks pointing outward from the epicenter of the blast. Scientists are pretty sure it was a comet or asteroid — about the same size as 2007 WD5, as it happens — that disintegrated from its own shock wave as it plowed through the atmosphere. (UFO enthusiasts have long been convinced it was a flying saucer that somehow made it across trillions of miles of interstellar space safely, only to blow up above Russia.) The scientific explanation would account for the aerial explosion, and also the fact that no crater has been found.

    Except that now maybe it has. An Italian team has measured seismic waves reflecting off a high-density spot in the bottom of the suspiciously crater-shaped Lake Cheko, which lies close to the event's ground zero. It could be a piece of the original object — and finding it could help investigators understand exactly what happened a century ago.

    If they find a burned-out flying-saucer engine, all bets are off.
  • edited December 2007
    Well, bye-bye Martians! Too bad we never met.
  • edited December 2007
    Just in case there's life on mars we'll just wait till it gets toasty'd before we go there ourselves and take things over. Still, were I a bettin' man, I wouldn't count on anything happening. 1 in 75 odds aren't very good.
  • edited December 2007
    Maybe the asteroid hit will reveal a huge underground cavern containing and ancient, martian city.

    Here's hoping.
  • edited January 2008
    World's biggest telescope to hunt for exoplanets

    art.big.telescope.jpg
    (PopSci.com) -- About half the size of a football field and 21 stories tall, the largest optical telescope ever constructed will use almost 1,000 mirrors to hunt for exoplanets -- and maybe even unlock the secrets of spacetime.

    How it works:

    Collect the light: Starlight hits the 138-foot-wide parabolic PRIMARY MIRROR -- an array of 984 hexagonal panels, each one 330 pounds, 4.8 feet in diameter and two inches thick. The panels are so heavy that gravity actually causes them to shift very slightly as the scope moves, so three actuators under each panel flex 10 times per second to keep the mirror properly aligned. The light bounces up to the 20-foot-wide MIRROR A.

    Reflect it: MIRROR A reflects and inverts light through a hole in MIRROR C onto the 13.8-foot MIRROR B, which directs light up to the reflective surface of MIRROR C.

    Sharpen it: MIRROR C is a thin two-millimeter glass shell stretched over 5,000 actuators that push or pull to reshape the mirror's surface 1,000 times per second. This rapid action performs so-called adaptive optics?realigning light distorted by the atmosphere into a sharp image. Astronomers calculate the correct setting for this mirror using bright reference stars.

    Send it to a sensor: Once corrected by the adaptive optics system, the light hits MIRROR D, 8.9 feet in diameter, which moves up to 20 times per second to keep the reference star aligned against vibrations from wind hitting the structure. This mirror reflects the starlight to a DETECTOR, which houses a camera that captures images, and to instruments that astronomers use to measure such phenomena as the speed at which the universe is expanding.

    Atmospheric turbulence and airborne particles scatter starlight as it heads toward ground-based telescopes, so astronomers calibrate the European Extremely Large Telescope's optics using bright reference stars in the same field of view as the target object.

    The rippled light wave hits each pixel on MIRROR C at slightly different times. The adaptive optics system morphs the mirror's surface so that the light hits each pixel at the same time, creating a clear image. But if an object has no nearby stars, astronomers make their own reference stars: Five or six lasers, known as a laser guide-star system, excite sodium ions 56 miles up in the atmosphere to create artificial beacons.

    The E-ELT will collect nearly as much dust as it does starlight, but simply washing the mirror with water isn't an option because the cracks between each panel could allow moisture into the electronics. Instead, telescope cleaners will spray ultrapure, cooled carbon dioxide "snow" over the primary mirror.

    The CO2 binds to the dust particles as it falls onto the mirror's surface and, as it evaporates, takes most of the dust with it. With normal wear and tear, the mirrors will need a fresh coating of reflective material, most likely aluminum, every few years.
  • edited January 2008
    European Extremely Large Telescope? That's not a very SCIENCE-y sounding name at all. Needs more... words whose meanings I don't already know.
  • edited January 2008
    Why is everything compared to the size of a football field?!
  • godgod
    edited January 2008
    Agentcel wrote: »
    Why is everything compared to the size of a football field?!
    We talked about that a few weeks ago in school. My answer is because in America, our measurements are retarded. To further prove this point, I asked if anyone actually knew how big an acre is, and one of the answer I got was "the ammount of land on which you can fit x horses (100 something)". Whether it's true or not, it makes about as much sence as some of our other measurements.
  • edited January 2008
    I attribute it to the mass of our population not knowing what 50 yards would be if football fields were not mentioned.
  • edited January 2008
    The metric system is the tool of the devil!
  • edited January 2008
    FDA OKs meat, milk from most cloned animals
    ATLANTA, Georgia (CNN) -- Meat and milk from most cloned animals are safe to eat, the Food and Drug Administration announced Tuesday.

    According to a 968-page "final risk assessment," the FDA finds no safety risks in meat from healthy cloned cows, pigs or goats or milk from cloned cows and their offspring.

    "Food products derived from cattle, swine, and goat clones pose no more risk than food derived from sexually reproduced animals," the report said.

    However, in the end, the FDA decided it needed more information to determine the safety of meat and milk from cloned sheep. The FDA also decided food from newborn cattle clones, "may pose some very limited human food consumption risk."

    The agency reportedly included hundreds of pages of raw data in the risk assessment, to help the public understand how it came to its findings.

    For years, a heated debate over the use of cloned animals for food production has stretched from Congress to cattle farms. The agency reached a preliminary decision in December 2006, after a four-year review, that milk and meat from cloned animals was safe for human consumption. Under government policy, the agency was required to collect more safety data before issuing a final decision.

    It is highly unlikely actual clones will be used in food production. A cloned cow costs $15,000 to $20,000 to create. More likely, experts said, the offspring of cloned animals will be used. Experts also say it will be three to five years before consumers see milk and meat from their offspring.

    Opponents of using cloned animals in food production are angry that the FDA is releasing its report now.

    "We think the FDA should pay attention to what Congress is asking them to do," say J.D. Hanson, policy analyst for the Center for Food Safety. "It looks like they are releasing it to sidestep what Congress has asked them to do."

    Another concern is economics. "People will start consuming less dairy and meat" out of uncertainty, suggested Michael Hansen, a senior scientist with Consumers Union. His group calls for more study and clear labeling.

    Last month, the Senate passed a measure that would bar the FDA from approving the proposal until it conducts further study of the potential health effects. The legislation also would require the Agriculture Department to examine consumer acceptance of cloned meats. The amendment was part of the Senate's $286 billion farm bill, which was passed in December.

    Other consumer groups are satisfied with the findings. "There are still unanswered questions about the use of cloned animals in the food supply, but the Food and Drug Administration has satisfactorily answered the safety question," the Center for Science in the Public Interest said in a statement. "While the safety of any food cannot be proven with absolute certainty, consumers should have confidence that meat and milk from cloned animals and their offspring will be safe."
  • edited January 2008
    I don't see what the big deal is. Cloning doesn't like, make radioactive mutant animals or anything.
  • edited January 2008
    I do not want to eat cloned meat or dairy products. And how can they honestly say it's safe?
    It is highly unlikely actual clones will be used in food production. A cloned cow costs $15,000 to $20,000 to create. More likely, experts said, the offspring of cloned animals will be used. Experts also say it will be three to five years before consumers see milk and meat from their offspring.
    Is there a meat shortage? I don't understand why they would want to do this. I think this will up the price on non-cloned meat products in the long run.
  • edited January 2008
    Garnet wrote: »
    I do not want to eat cloned meat or dairy products. And how can they honestly say it's safe?
    Are they not just cows?
  • edited January 2008
    hlavco wrote: »
    Are they not just cows?

    And not only that, but aren't they exactly the same as the cows they were cloned from?
  • edited January 2008
    Originally Posted by hlavco:
    Are they not just cows?
    My statement was general because the article includes other animals(goats and pigs). Also, I was referring toward the end product. :cool:

    Deku: I believe they would have the same genetic makeup, but their appearance(color markings and such) might be different.
  • edited January 2008
    Well, if they have the same genetic makeup, then they will naturally be the same color.

    Besides, they said that because it costs 15-20K to clone a cow, they'll probably just use the offspring for food. So, they'd be cloned into existence to have lots of sex. Sounds like a good life.
  • edited January 2008
    Exactly. I think cloned animals will mainly be used to reproduce beneficial genetic strains. Have a cow that produces REALLY good offspring? Clone it a few thousand times and sell it as a breeder to dairy farms!

    And seriously, as Hamelin said, it's not like they're irradiated or mutated or anything. Being frightened of cloned animals is about the same as being frightened at genetically modified vegetables, and if you're afraid of those, you need to be afraid of almost everything we eat.
  • edited January 2008
    I respect your opinion on this matter. I am not frightened by cloned animals or their offspring.I would rather eat meat without the cloning factor. As for genetically modified plants,yes, it's nearly impossible to avoid those foods especially corn. I think it is better to eat things less processed when possible.

    Well, gentlemen and ladies, I think I shall bow out of this discussion now as I have made my feelings clear on this subject. :)
  • edited January 2008
    My apologies. I did not mean to put words into your mouth. =) And of course, I respect your opinion as well.

    I was merely saying that genetic modification and cloning aren't as scary as some groups would have you think. Often with genetic modification, the plants are bred in certain ways to bring about certain results. The only science involved, often, is the calculations used to choose which plants to breed. Corn and potatoes were genetically modified long before we even knew that we are made up of cells.
  • edited January 2008
    Irrational fears aside, a cloned mammal does indeed have thus far mysterious cellular degeneration goin' down. This was discovered back when Dolly the sheep was cloned; her clone didn't survive to adulthood, because all her cells started out at the age they were when the clone occurred. As far as I'm aware, there haven't been many studies into this phenomenon or how it might affect us when we're eating pre-aged cells, but they're right in saying that this is not a hereditary ailment, and as long as the animal reaches child-rearing age, the offspring turn out perfectly normal. The biggest concern with rampant cloning of so-called ideal livestock is a lack of diversity in the gene pool, which makes herds susceptible to genetic diseases and all sorts of fun stuff.

    I don't have any inherent problem with the idea of eating cloned animals, I just think they shouldn't be so quick to market. The FDA sure did usher it through quickly compared to other untested foods and/or drugs.
  • edited January 2008
    Area 51 gets a new name.
    The Air Force’s classified test range at Groom Lake, Nev., has never lacked for evocative nicknames — it and its restricted airspace have been called Dreamland, Paradise Ranch, The Box and, most famously, Area 51. Now there’s a less romantic moniker to throw on the pile: “Homey Airport,” according to a few civilian aviation journals.

    “Homey Airport” now appears as the official name for a certain air base near a certain dry lake bed in Nevada, according to reports in the Web site of the Aircraft Owners and Pilots Association, as well as the Daily Aviator blog and others. New editions of flight planning software and civilian aviators’ GPS gear lists the name and the official designation “KXTA” — which online wags have speculated stands for “extraterrestrial airport.” (The “k” designation indicates only that the field is in the U.S., according to the Federal Aviation Administration.)

    Capt. Jessica Martin, a spokeswoman for Nellis Air Force Base, which sits 85 miles south of Homey Airport and is responsible for the airspace and any ground facilities, said that “we already know about the designation, but it doesn’t have any effect on operations at the base.”

    Martin said she didn’t know the origin of the name “Homey Airport.”

    Featured in movies, TV shows and video games, Area 51 is likely the most famous top-secret facility in the world and a favorite component of UFO and military conspiracy theories.

    The Department of Defense didn’t even acknowledge the base existed until 1994, when former base employees sued the government and claimed they’d been poisoned by hazardous materials used at the base for research into stealth technology.

    Although the base and its work have long been highly classified, many of the aircraft tested there through the years are publicly familiar: the U2 and SR-71 Blackbird spy planes and the F-117 Nighthawk stealth fighter all flew first off the long runways and dry lakebeds at Groom Lake.

    Some enthusiasts believe that work continues there today on advanced aircraft — including unmanned aerial vehicles, high-speed reconnaissance craft and even high-altitude blimps — though alien conspiracy buffs also speculate that Area 51’s high profile has forced officials to move much of the top-secret stuff to the Army’s Dugway Proving Ground in Utah.

    Me an' my homies be chillin' at Homey Airport.
  • edited January 2008
    Now all those video games have to be renamed too.
  • edited January 2008
    I would love to have heard that conversation.

    "Hey Bob, now that Area 51 is public knowledge, and we don't really do as much secret stuff here, maybe we should give it a new name. Somethign more, erm... I don't know, welcoming and friendly. Something that says, 'hey there, come on in, make youself at home.' Yeah, that's it something kind of homey."

    "How about Homey Airport?"

    "BRILLIANT!"
  • edited January 2008
    ...and then the two of them have a Guinness?
  • edited January 2008
    If everyone who said "Brilliant!" drank a Guinness afterwards, the British would always be drunk.

    Oh wait...
  • edited January 2008
    Takeru wrote: »
    If everyone who said "Brilliant!" drank a Guinness afterwards, the British would always be drunk.

    Oh wait...

    lol... nice. :D
  • edited February 2008
    Come on people! SCIENCE! This thread is practically dead.

    Ancient "devil frog" may have eaten baby dinosaurs
    WASHINGTON - It was the biggest, baddest, meanest froggy ever to have hopped on Earth.

    Scientists on Monday announced the discovery in northwestern Madagascar of a bulky amphibian dubbed the "devil frog" that lived 65 million to 70 million years ago and was so nasty it may have eaten newborn dinosaurs.

    This brute was larger than any frog living today and may be the biggest frog ever to have existed, according to paleontologist David Krause of Stony Brook University in Stony Brook, New York, one of the scientists who found the remains.

    Its name, Beelzebufo ampinga, came from Beelzebub, the Greek for devil, and bufo -- Latin for toad. Ampinga means "shield," named for an armor-like part of its anatomy.

    Beelzebufo (pronounced bee-el-zeh-BOOF-oh) was 16 inches

    long and weighed an estimated 10 pounds (4.5 kg).

    It was powerfully built and possessed a very wide mouth and powerful jaws. It probably didn't dine daintily.

    "It's not outside the realm of possibility that Beelzebufo took down lizards and mammals and smaller frogs, and even -- considering its size -- possibly hatchling dinosaurs," Krause said in a telephone interview.

    "It would have been quite mean," added paleontologist Susan Evans of University College London, another of the scientists.

    Their findings were published in the journal Proceedings of the National Academy of Sciences.

    Even though it lived far away, Beelzebufo appears to be closely related to a group of frogs that live today in South America, the scientists said. They are nicknamed "Pac-Man" frogs due to their huge mouths. Some have little horns on their heads, and the scientists think Beelzebufo also may have had horns -- a fitting touch for the "devil frog."

    Beelzebufo was bigger than any of its South American kin or any other living frog -- "as if it was on steroids," Krause said. The largest one today is the goliath frog of West Africa, up to 12.5 inches long and 7.2 pounds (3.3 kg).

    The presence of Beelzebufo in Madagascar and its modern relatives in South America is the latest sign a long-lost land bridge once may have linked Madagascar to Antarctica -- much warmer then -- and South America, the scientists said.

    That would have let animals move overland among those land masses. Fossils have been found of other animals in Madagascar from Beelzebufo's time similar to South American ones.

    KING OF FROGS

    The first frogs appeared about 180 million years ago, and their basic body plan has remained unchanged. Beelzebufo lived during the Cretaceous Period at the end of the age of dinosaurs, which went extinct along with many other types of animals 65 million years ago when a huge space rock clobbered Earth.

    Beelzebufo did not live an aquatic lifestyle, hopping among lily pads, the scientists said. Instead, it lived in a semi-arid environment and may have hunted like its modern-day relatives, which camouflage themselves and jump out at prey.

    Its first fragmentary fossils were found in 1993, and the scientists have since assembled enough fragments to piece its remains together like a jigsaw puzzle, Krause said.

    While it was the king of frogs, Beelzebufo is not the largest amphibian ever to have lived. Many reached truly astounding dimensions, such as the crocodile-like Prionosuchus that grew to an estimated 30 feet during the Permian Period, which ended about 250 million years ago.
  • edited February 2008
    Double dose and double post of SCIENCE!

    Killer Robots... Friend or Foe?
    Thousands of robots are already on the battlefield in Iraq and Afghanistan, but what happens when you hand the robot a gun and turn it loose?

    Some researchers fear that giving military robots autonomy as well as ammo is the first step toward a "Terminator"-style nightmare, while others suggest that in some scenarios, weapon-wielding robots could someday act more humanely than humans.

    The pros and cons of killer robots are taking center stage Wednesday in London, at what's considered the world's oldest military think tank, the Royal United Services Institute.

    On one side of the issue is Ronald Arkin, a robotics researcher at Georgia Tech who is working on a Pentagon-funded project to build a sense of ethics into battlefield robots - "an artificial conscience, if you will," he told me.

    "The basic rule is to try to engineer a system that will comply as best it can, given the information that it has, with the laws of war," Arkin explained. "And it's my belief that eventually we can do better than humans in this regard."

    On the other side is Noel Sharkey, a robotics expert at Britain's University of Sheffield who served as chief judge for the long-running TV show "Robot Wars."

    Nowadays, Sharkey is sounding the alarm about the prospect of real-life robot wars: He's calling for an international ban on autonomous weapon systems until it can be shown that they can obey the laws of war.

    "I think we should be addressing this immediately," Sharkey told me. "I think we've already stepped over the line."

    Killer robots aren't on their own ... yet
    That doesn't mean killer robots are on the loose. To date, the battlefield 'bots have been used as not-so-autonomous extensions of human warfighting capabilities. For example, the missile-armed Predator drones that have played such a prominent role in Iraq and Afghanistan are remote-controlled by teams of living, breathing pilots.

    On the ground, robots have traditionally done reconnaissance or hunted for roadside bombs. Just recently, the Pentagon just went through a tangled procurement process to order up to 3,000 next-generation machines. (After a legal battle, the contract was won by iRobot, which also makes the Roomba vacuum cleaner and other robotic helpers.)

    Last year, the Pentagon started sending gun-toting robots to Iraq, but even those robots aren't designed for autonomous operation. Instead, they're remote-controlled by human operators and are equipped with fail-safe systems that shut them down if they go haywire.

    What worries Sharkey is that the military may be on a slippery slope leading to a robotic arms race. "My real concern is that the policies are going to make themselves, that the 'autonomization' of weapons will creep in piecemeal," he told me.

    For example, Sharkey pointed out that the Pentagon is already on a path to make a third of its ground combat vehicles autonomous by 2015. "Then you'll put a weapon in one of them, and then it will gradually creep in bit by bit.," he said.

    He also pointed to the Pentagon's roadmap for billions of dollars' worth of robotic research over the next 25 years. As the United States and its allies put more and more robots on the battlefield, their rivals will surely follow. "Once you build them, they're easy to copy," Sharkey said. "The trouble is that we can't really put the genie back in the bottle."

    Even if the United States takes care to build robots with a "conscience," others may feel under no pressure to do likewise. A couple of years ago, Iranian-backed Hezbollah guerrillas sent a remote-controlled drone over Israel, and Sharkey said al-Qaida and other terrorists could follow suit with their own breeds of robo-bombers.

    "If you don't really give a toss, you can just put an autonomous weapon running into a crowd anywhere," Sharkey said. "It's only a matter of time before that happens."

    Killer robots with a conscience?
    Arkin agrees with Sharkey that it's high time to start thinking about the implications of autonomous weapon systems.

    "I think that's a reasonable debate, and there's good reason to have that debate at this time, just so we understand what we're creating," he said. "I would be content if it was decided that autonomous systems have to be banned from the battlefield completely."

    But when it comes to designing the combat systems of the future, Arkin argued that there should be a place for autonomy, or at least an embedded sense of ethics. He pointed out that humans haven't always had a good track record on battlefield behavior.

    "Human performance, unfortunately, is a relatively low bar," Arkin said.

    One of Arkin's suggestions would apply even if a robot is under human control: The robot should be able to sense if something wasn't right about what it was being asked to do - and then require the human operator to override the robot's artificial conscience.

    In other scenarios, the data flooding in about a potentially threatening encounter might be so overwhelming that mere mortals would not be able to process the input in time to make the right decision. "Ultimately, robots will have more sensors and better sensors than humans have to see the situation," Arkin said.

    Arkin said he doesn't advocate the idea of creating robot armies to sweep over a battlefield. Rather, they would be used for targeted applications: For example, once an urban area is cleared of civilians, a robot could be set up to watch out for snipers and fire back autonomously, he said.

    "The impact of the research I'm doing is, hopefully, going to save lives," he said.

    But Arkin described his efforts as mere "baby steps" toward the creation of battlebots with a conscience. "There are no milestones or timetables for doing this right now," he said. "We're pioneering this work to see where it would lead."

    New laws of robotics
    This work goes way beyond science-fiction author Isaac Asimov's Three Laws of Robotics, which supposedly ruled out scenarios where robots could harm humans.

    "Asimov contributed greatly in the sense that he put up a straw man to get the debate going on robotics," Arkin said. "But it's not a basis for morality. He created [the Three Laws] deliberately with gaps so you could have some interesting stories."

    Even without the Three Laws, there's plenty in today's debate over battlefield robotics to keep novelists and philosophers busy: Is it immoral to wage robotic war on humans? How many civilian casualties are acceptable when a robot is doing the fighting? If a killer robot goes haywire, who (or what) goes before the war-crimes tribunal?

    Sharkey said such questions should go before an international body that has the power to develop a treaty on autonomous weapons.

    "In 1950, The New York Times was calling for a U.N. commission on robotic weapons," Sharkey said. "Here we are, 57 years later, and it's actually coming to pass - and we still haven't got it."