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In 1980, only 86 near-Earth asteroids and comets were known to exist. By 1990, the figure had risen to 170; by 2000, it was 921; as of this writing, it is 5,388. The Jet Propulsion Laboratory, part of NASA, keeps a running tally at www.neo.jpl.nasa.gov/stats. Ten years ago, 244 near-Earth space rocks one kilometer across or more—the size that would cause global calamity—were known to exist; now 741 are. Of the recently discovered nearby space objects, NASA has classified 186 as “impact risks” (details about these rocks are at www.neo.jpl.nasa.gov/risk). And because most space-rock searches to date have been low-budget...

ALBUQUERQUE, N.M. - An asteroid that exploded over Siberia a century ago, leaving 800 square miles of scorched or blown down trees, wasn't nearly as large as previously thought, a researcher concludes, suggesting a greater danger for Earth. According to supercomputer simulations by Sandia National Laboratories physicist Mark Boslough, the asteroid that destroyed the forest at Tunguska in Siberia in June 1908 had a blast force equivalent to one-quarter to one-third of the 10- to 20-megaton range scientists previously estimated. Better understanding of what happened at Tunguska will allow for better estimates of risk that would allow policymakers to decide...

Today, I present my handy guide to choosing a presidential candidate. I call it the Asteroid Test. Imagine this scenario: A mile-wide asteroid is hurtling toward Earth. Scientists say a collision is imminent and that it will obliterate life on the planet. Now ask yourself this: What would each presidential candidate do? (Disregard my own candidacy, which is strictly a Flip Side phenomenon.) Here's how I see some of our presidential hopefuls reacting when I run through the asteroid exercise: • Joe Biden: He would speak at great length on how to solve the crisis. His plan might not work,...

Smaller asteroids may pose greater danger than previously believed INCINERATION POSSIBLE - Fine points of the "fireball" that might be expected from an asteroid exploding in Earth's atmosphere are indicated in a supercomputer simulation devised by a team led by Sandia researcher Mark Boslough. (Photo by Randy Montoya ) Download 300dpi JPEG image (Media are welcome to download/publish this image with related news stories.)ALBUQUERQUE, N.M. — The stunning amount of forest devastation at Tunguska a century ago in Siberia may have been caused by an asteroid only a fraction as large as previously published estimates, Sandia National Laboratories supercomputer simulations...

Deflected asteroids may keep coming back 17 November 2007 What goes around comes around. Unfortunately, no such karma figures in plans to deflect asteroids on a collision course with Earth, a hearing of the US House Science and Technology Committee was told last week. One big whack will deflect an asteroid temporarily, but does not guarantee safety next time its orbit brings it close. Asteroid researchers have long debated the merits of deflecting asteroids with a powerful blast such as a nuclear explosion. However, Rusty Schweickart, who heads an asteroid research group called the B612 Foundation, told the committee that...

This coming January, Ad Astra Rocket Company will test the VX-200, a full-scale ground prototype of the variable specific impulse magnetoplasma rocket (VASIMIR), first conceived in 1979 by the company's president and CEO, astronaut and plasma physicist Franklin Chang Diaz. The rocket is an attempt to improve on current space-propulsion technologies, and it would use hot plasma, heated by radio waves and controlled by a magnetic field, for propulsion. Chang Diaz believes that the system would allow rockets to travel through space at higher speeds, with greater fuel efficiency. If the prototype demonstrates sufficient efficiency, thrust, and specific impulse on...

NASA this weekend is set to launch a spacecraft that will journey to the asteroid belt that lies between Mars and Jupiter, a mission that involves a rendezvous with two of the solar system's largest asteroids. Seeking clues about the birth of the solar system, the Dawn spacecraft will first encounter Vesta, the smaller of the two bodies, four years from now. In 2015, it will meet up with Ceres, which carries the status of both asteroid and, like Pluto, dwarf planet. "We're trying to go back in time as well as to go out there in space," said planetary...

There?s been an upsurge in interest in crewed missions to visit a near Earth asteroid. The prospects of new spacecraft, along with the more distant, yet still possible, larger rockets to push the new craft to the Moon, Mars, and beyond have fired the imaginations of scientists and laymen alike. Many say that a near Earth asteroid is the next logical step after the United States? return to the Moon, sometime before 2020. Others say that an asteroid mission could be taken even before the return to the Moon. They say such a mission could alleviate the ?been there, done...

China and US at highest risk of damage from asteroids 14:01 27 March 2007 NewScientist.com news service David Shiga Simulations show the asteroid impact locations that would produce the most casualties in red. The Pacific coast of Asia is a particularly deadly place for an asteroid to strike because of tsunamis, while a direct strike on some densely populated inland areas could also cause a heavy toll (Illustration: Nick Bailey et al/University of Southampton)The worst places for an asteroid to strike in terms of infrastructure damage are shown here in red, with the north Atlantic appearing prominently (Illustration: Nick Bailey...

A fleet of exploding probes could prepare the way for warding off hazardous asteroids. Several of the small spherical robots would land on a single asteroid, some exploding while others listen for vibrations that could reveal the object's inner structure. NASA has a list of more than 800 asteroids considered to be potentially hazardous because their orbits carry them close to Earth's. If one of them is found to be on a collision course, knowing its physical properties will be crucial in devising a mission to divert it.

HONOLULU - NASA astronaut and former University of Hawaii solar physicist Edward Lu is calling for a new spacecraft that would divert asteroids on a path to slam into Earth. The small space tractor, costing between $200 million and $300 million, would hover near an asteroid to exert enough gravitational pull that the space rock's orbit would change and a collision with our planet would be averted, Lu said before a crowd packed into a 300-capacity auditorium at the University of Hawaii-Manoa Monday night. "We're only trying to get a really tiny change in the velocity of the asteroid to...

The new measurements pinpoint the location of a disk of warm dust that surrounds Zeta Leporis. The dust lies about the same distance from the star as the solar system's asteroid belt lies from the sun, Margaret M. Moerchen and Charles M. Telesco of the University of Florida in Gainesville and their colleagues report in an upcoming Astrophysical Journal Letters... The close-in dust around Zeta Leporis probably arose when several asteroids bumped into each other, grinding rock into a fine spray of particles, or when a large asteroid, perhaps 100 kilometers in diameter, suffered a cataclysmic wallop, Moerchen and Telesco...

At the southern end of Madagascar lie four enormous wedge-shaped sediment deposits, called chevrons, that are composed of material from the ocean floor. Each covers twice the area of Manhattan with sediment as deep as the Chrysler Building is high. On close inspection, the chevron deposits contain deep ocean microfossils that are fused with a medley of metals typically formed by cosmic impacts. And all of them point in the same direction — toward the middle of the Indian Ocean where a newly discovered crater, 18 miles in diameter, lies 12,500 feet below the surface. The explanation is obvious to...

According to the Russian astronomer Nikolai Fedorovsky, a giant comet flying at top speed is bound for Earth. Should the comet stay on the collision course, it may hit the planet in late October. The impact will cause devastating tsunamis, earthquakes and avalanches, says Fedorovsky. He saw the killer comet in a telescope two weeks ago. He managed to calculate the comet’s trajectory. We got in touch with Nikolai Fedorovsky: “I’m not trying to scare anybody, I just want to warn the public,” sums up Fedorovsky. “We should pay attention to this suspicious celestial body. We could obtain more accurate...

PRAGUE, Czech Republic — Astronomers are stepping up the global effort to scan the skies for "near-Earth objects": asteroids and comets on a potential collision course with the planet and big enough to pack a deadly punch. The International Astronomical Union said Thursday it has set up a special task force to broaden and sharpen its focus on impact threats.

May 8 2006 12:01PM Chance of asteroids hitting earth very slim - Russian astronomers ST.PETERSBURG/MOSCOW. May 8 (Interfax) - The chance of a large asteroid hitting our planet in the next 100 years is "extremely slim," astronomer Sergei Smirnov of the Pulkovo Main Observatory told journalists. Smirnov dismissed as unfounded reports that a giant asteroid could strike the Earth in the summer of 2008 and said this is clear from experts' calculations. U.S. astronomers have lately been closely monitoring a large newly discovered asteroid, which they said has a very little chance of colliding with the earth. The odds of...

NASA announced yesterday that it was resurrecting Dawn, a spacecraft that will visit two of the solar system's largest asteroids, less than a month after killing the mission. "I'm astonished," said Lucy-Ann McFadden, an astronomer at the University of Maryland and a member of the mission's science team. "I'm excited. I'm ready to go. I was still in denial that we got canceled."

AN asteroid capable of devastating an area the size of a sub-continent has about a one in 1000 risk of hitting Earth early next century, NASA said today. The rock, 2004 VD17, is about 500m long and has a mass of nearly a billion tonnes. If it hit Earth it would deliver 10,000 megatonnes of energy, equivalent to all the world's nuclear weapons. Spotted on November 27 2004, VD17 was identified as potentially crossing Earth's orbit, with a one in 3000 risk of collision on May 4, 2102. Further observations and calculations have prompted the risk on that day to...

LOS ANGELES (AP)—A NASA spacecraft built to explore two of the solar system's largest asteroids won't launch this year because the space agency is dealing with cost overruns and technical issues in the project. The planned summer launch of the Dawn spacecraft has been indefinitely postponed, said Andrew Dantzler, director of NASA's solar system division. Mission managers had been ordered to halt work on Dawn last fall while the project was assessed by an independent review team, which is expected to present its findings to NASA on Jan. 27. Even if NASA gives Dawn the green light, it would take...

This small body, known as 2001 QR322, leads Neptune around its orbit in such a way as to maintain, on average, approximately equal distance from Neptune and the Sun. As such, it mimics the Trojan asteroids of Jupiter which orbit the Sun in two clouds approximately 60 degrees ahead of and behind Jupiter. The first Jovian Trojan was discovered in 1906 and approximately 1,560 such objects are known today. However, until the discovery of 2001 QR322, Trojan-like objects associated with other giant planets had not been found.

From a human perspective, Earth-crossing asteroids can have good timing or bad timing. Good timing is when the asteroid and the Earth don't meet. Bad timing is when they do. Astronomers say that a 1,000-foot diameter asteroid discovered last year may have bad timing. There is a slight possibility that the rock, 99942 Apophis, will hit Earth in 2036 after coming within about 20,000 miles in 2029. A collision could cause regional devastation on a scale far worse than last year's tsunami. "The most likely thing is that it is not going to be a threat," said Rusty Schweikart, the...

· Three-year study will use computer simulations · 'It's a small risk, but with a high consequence' British scientists are set to go where only Bruce Willis has gone before: chasing after asteroids on a collision course with Earth. In a three-year £300,000 study funded by the government-backed Engineering and Physical Sciences Research Council, engineers will use computer simulations to work out the feasibility of changing the direction of asteroids. "It's clear from geological records that the Earth has been impacted in the past by large objects," said Colin McInnes of Strathclyde University. Although none of the space objects currently...

ALBUQUERQUE, N.M. - Dust from asteroids entering the atmosphere may influence Earth's weather more than previously believed, researchers have found. The asteroid's dust trail as seen by lidar at Davis, Antarctica. The plot shows the strength of the vertical laser light scattered back from the atmosphere as a function of time and altitude above mean sea level. The dust trail, blown by the stratospheric winds, moved through the beam. (Image courtesy of Sandia National Laboratories) In a study to be published this week in the journal Nature, scientists from the Australian Antarctic Division, the University of Western Ontario, the Aerospace...

Imagine a future in which terrorists seize an embassy and police can send in a remote-controlled insect outfitted with a microscopic video camera that reveals where the gunmen are hiding and what kind of weapons they hold. Or a time when adventure travelers fly to the moon to spend a week at a space colony under the glittering lunar skies--in the way they now visit Antarctica or the North Slope of Alaska. Or a U.S. constitutional convention where delegates draft a new governing document that allows the rest of the world a say in American decision-making. Sound far-fetched? Over 1,000...

"Why do you care about politics? Why do you care about what is happening in the world around you? Most everyone seems to want a better world to live in and a better world for their posterity. Considering this, it seems natural that we as concerned citizens should be concerned with the potential of our world's demise. Asteroid '2004 MN4' is set to be headed towards planet Earth. We now know that there is now an approximately one-in-forty-five chance that it will hit us. Thanks to some number crunching a comrade of mine has done, I can report the following...

In a sign that the issue is moving up the space community's agenda, researchers from the University of Glasgow will work with ESA and satellite specialist EADS Astrium to determine the best method of deflecting asteroids from a collision course with Earth. They will consider everything from hitting the objects with nuclear weapons to dragging them with a solar sail, and devise accurate mission simulations. Until now space agencies have neglected the topic of diverting asteroids, according to Dr Gianmarco Radice, project leader and member of the space systems engineering research group at Glasgow's department of aerospace engineering. 'Very little...

Members of a special expedition researching the site of the famous Tunguska meteorite fall have claimed they had discovered parts of an extraterrestrial device. The expedition, organized by the Siberian Public State Foundation “Tunguska Space Phenomenon” completed its work on the scene of Tunguska meteorite fall on August 9. It was the first expedition to the region since 2000. Guided by the space photos, the researchers scanned a wider territory in the vicinity of the Poligusa village for parts of the space object that crashed into Earth in 1908 and was later called the Tunguska meteorite. The scientists claim that...

Probe to 'look inside' asteroids By Paul Rincon BBC News Online science staff in Paris, France Studies of asteroids would aid Earth-protection strategies A new space mission concept unveiled at a Paris conference aims to look inside asteroids to reveal how they are made. Deep Interior would use radar to probe the origin and evolution of two near-Earth objects less than 1km across. The mission, which could launch some time later this decade, would also give clues to how the planets evolved. The perceived threat of asteroids colliding with our planet has renewed interest in space missions to understand these...

Hi, I'm sure you are all unaware of the hype! Currently going on around the World via the 'Internet' regarding Comet strikes, Asteroid strikes and 'The end of the World' Armageddon debates. I'm not a professional astronomer, astrologer or a conspiracy theorist, but I can't believe the UK or the WORLD'S mainstream media hasn't picked up on the highly increased number of meteor impacts and sightings over the last few weeks. Why could this be? In the astronomical aspect of things this is huge news. Here are some of the main news headlines over the last few weeks from around...

Picture credit: TheCabal"I will never cower before any master nor bend to any threat"LINK TO THREAD TEN Iran seeks swap of Brits for suicide attackers Report says 40 Revolutionary Guard 'volunteers' held by UK Iran apprehended British military personnel and Navy vessels earlier this week in order to secure release of 40 "suicide operations volunteers" held by the UK, according to an Iranian Revolutionary Guard source. The source told the London Arabic-language daily Al-Sharq Al-Awsat that the British Army command in Iraq received the demand from the Revolutionary Guard, reported the Middle East Media Research Institute. According to the source,...

Scientists are concerned about terrorism like many of us are today, but not from people -- from outer space. Asteroids and comets constantly spin near us, threatening death and destruction. A dead-on hit by the largest of these cosmic cannonballs could mean the end of life as we know it. Now is the time for a new age of exploration and discovery, to go seek out the universe -- but maybe it's the reverse -- the universe may be coming after us, in the form of comets or asteroids. Physics and astronomy professors like Gary Copeland at Old Dominion University...

At the end of 2003, there were 2600 known Near Earth Asteroids (NEAs), and of these 691 are brighter than absolute magnitude H=18, which is taken to correspond to 1 km diameter. Of these, 131 are classed as PHAs (potentially hazardous asteroids) larger than 1 km. These data from Alan Chamberlin are posted on the JPL/NASA NEO Program Office website . For comparison, there are estimated to be a total of 1100 +/- 100 NEAs larger than 1 km. Thus at the end of 2003 we had found 63 percent of these NEAs. Recently there appears to have been a...

Following are parts of the testimony presented by astronauts Rusty Schweickart and Ed Lu before the U.S. Senate Subcommittee on Science, Technology, and Space at a hearing April 7, 2004. Schweickart was one of the Apollo astronauts, and Lu recently returned to Earth after a 6-month tour of duty on the International Space Station. Their discussions deal primarily with a proposed demonstration mission to develop technology for deflecting an asteroid. For their full testimony, see the news archive at http://impact.arc.nasa.gov. Others testifying at the same hearing include Wayne Van Citters, Director of the Division of Astronomical Sciences, National Science Foundation;...

An asteroid flew past Earth last week so close that it nearly entered an orbital halo where weather satellites roam. Scientists spotted it March 15 and watched it zoom by just three days later. It posed no threat, but there are hundreds of thousands more where that one came from.And while asteroid 2004 FH, as it is known, was watched calmly by astronomers, a more frightening scenario unfolded two months earlier:    More Stories Animation of Asteroid's Close Brush with Earth NASA Report: Expand Search to Include Small Asteroids Asteroids and Secrecy: If End is Nigh, Do You Want to Know?...

January 14 could have been a bad day for George Bush. As the president was preparing to announce America's return to the moon in a speech at the headquarters of Nasa, he was almost asked to deliver a very different message: that the Earth could suffer a devastating asteroid strike within 24 hours. Astronomers have revealed that during a "nine-hour crisis" the night before Mr Bush's speech they believed there was a one in four chance an asteroid would hit the planet in 36 hours. Had it not been for a break in the clouds that allowed an amateur astronomer...

Sunlight's gentle nudge on asteroids detected 19:00 04 December 03 NewScientist.com news service Astronomers have detected the delicate force of sunlight on an asteroid's orbit for the first time. The long-predicted effect has been blamed for propelling some asteroid fragments from the Solar System's main asteroid belt into the region near Earth, where they can threaten the planet. But its subtle action on asteroid orbits has been difficult to measure with optical telescopes. Instead, Steve Chesley, Steve Ostro and colleagues at NASA's Jet Propulsion Lab in Pasadena, California, used the radar range finder at Arecibo in Puerto Rico. They used...

Catastrophic asteroid impacts are gaining a credible edge over violent volcanic eruptions as the greatest killers Earth has ever seen, according to two pieces of scientific detective work reported in tomorrow's issue of the journal Science. The first cataclysm in question occurred about 250 million years ago, when according to the fossil record more than 90 percent of Earth's marine species and 70 percent of life on land perished. The event is known as the Permian-Triassic (P-T for short) mass extinction, named because it falls on the boundary between the two geological eras. The second event, known as the Cretaceous-Tertiary...

Source: Imperial College Of Science, Technology And Medicine Date: 2003-07-23 Fewer Earthbound Asteroids Will Hit Home; Scientists Say Pancake Model Of Asteroid Impact Won’t Stick July 16, 2003 -- Scientists report in Nature today that significantly fewer asteroids could hit the Earth's surface than previously reckoned. Researchers from Imperial College London and the Russian Academy of Sciences have built a computer simulation that predicts whether asteroids with a diameter up to one kilometre (km) will explode in the atmosphere or hit the surface. The results indicate that asteroids with a diameter greater than 200 metres (the length of two football...

<p>Massive tsunamis, miles of raging forest fires, a stratosphere clogged with enough debris to obscure the sun -- even a relatively small asteroid striking Earth would wreak enough havoc to end civilization.</p> <p>"It's not whether it's going to happen," said Bruce Weaver, director of Monterey Institute for Research in Astronomy (MIRA). "The question is how long it will be (until one hits)."</p>

Scientists studying rocks near an ancient asteroid impact structure in South Australian have uncovered evidence that could change current theories explaining how life on Earth rapidly diversified about 580 million years ago. Dr Kath Grey of the Western Australian Department of Industry and Resources' Geological survey and an ACA associate researcher, Prof Malcolm Walter, Director of the ACA and Dr Clive Calver of the Tasmanian Department of Mineral Resources challenge the idea that 'Snowball Earth' - an intense period of glaciation about 600 million years ago, triggered the evolution of simple life forms into more complex and familiar species. In...

NEW STUDY: SOME ASTEROIDS MAY BE LAYERED LIKE ONIONS A new study of several meteorites collected on Earth and thought to have come from the same large asteroid reveal the structure of the parent space rock to have been something like an onion, with layer upon layer of differing structure. The asteroid, long ago destroyed in a collision, was once hot enough to have a molten core and cooled from the outside inward, the research shows, confirming a long-held expectation that had eluded supporting research. Asteroids are leftovers of planet formation. While some rocks got together to build planets about...

Maine Crater Related to Dino-Killer Asteroid? By Larry O'Hanlon, Discovery News April 3, 2003 — The evidence is still skimpy, but there is a chance that the dino killer asteroid was not alone when it walloped the Earth 65 million years ago. A possible second crater, at least as big or bigger than the famous Chicxulub crater off Mexico's Yucatan peninsula, may have been created by a second hit moments after Chicxulub and off the coast of Maine. "It probably is a crater, but we really don't have age data," said marine geologist Dallas Abbott Lamont-Doherty Earth Observatory at Columbia...

Clementine image of the moon showing the fresh crater believed to be the impact site for the event photographed on November 15, 1953 by amateur astronomer Dr. Leon Stuart. Full press release: NASA Solves Half-Century Old Moon Mystery (click link for additional pictures, including the "Stuart Event" picture of the Moon) In the early morning hours of Nov. 15, 1953, an amateur astronomer in Oklahoma photographed what he believed to be a massive, white-hot fireball of vaporized rock rising from the center of the Moon's face. If his theory was right, Dr. Leon Stuart would be the first and only...

There's an old joke about the man who asks his neighbor to turn down the loud, raucous noise emitting from her stereo."What's the matter, are you a music hater?" "No," he replies, "I'm a music lover." I'm reminded of this by the calls of some over the years to end the space-shuttle program, even (perhaps especially) by people who are frustrated by our lack of progress in space. In the wake of the latest tragedy, the calls will undoubtedly grow louder, but in many cases, even if correct, they will be for the wrong reasons, and may not lead to...

'Ready to tackle Armageddon' By Ivan Noble BBC News Online science staff A space mission to knock a potential rogue asteroid off course is undergoing feasibility studies with money from the European Space Agency (Esa). We believe that the outcome of this mission would be good science Jose-Antonio GonzalezDeimos-Space A Spanish company, Deimos-Space, is designing the mission and hopes its plans will convince Esa to give the go-ahead for a full scale test on a real asteroid. The company has come up with a plan, which it calls the Don Quixote mission, to launch a pair of probe spacecraft called...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 August 17 Asteroid 2002 NY40 Credit: K. Zwintz (Univ. Viena), H. Tirado and A. Gomez (CTIO, NOAO) Explanation: Asteroid 2002 NY40 will fly by planet Earth early in the morning August 18 Universal Time (late in the evening August 17 Eastern Daylight Time). Approaching to within about 530,000 kilometers or 1.3 times the Earth-Moon distance 2002 NY40 will definitely not be close enough to pose any danger...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 August 11 A Perseid Meteor Credit & Copyright: S. Kohle & B. Koch, Bonn University Explanation: The ongoing Perseid Meteor Shower should be at its strongest on August 12 and 13. The best time to watch will be between 2:00 AM and dawn on Monday morning (so plan on setting your alarm tonight!) and then again on Tuesday. In dark, moonless, predawn skies you may see dozens...

Superfast VASIMR Rocket in Funding Limbo By Leonard David Senior Space Writer posted: 07:00 am ET 07 August 2002 Trimming travel time between Earth and various space targets is crucial to keeping human and robotic surveys of the solar system prospering into the 21st Century.Faster rockets cut back on an astronaut's radiation intake. Being a space speedster may also reduce loss of bone and muscle mass, as well as limit circulatory changes due to prolonged microgravity exposure.One approach to express lane rocketry is tagged the Variable Specific Impulse Magnetoplasma Rocket (VASIMR). With VASIMR's oomph, a 10-month one-way trek to Mars...

NEWS   SPORT   WEATHER   WORLD SERVICE   A-Z INDEX    SEARCH   You are in: Science/Nature   News Front Page Africa Americas Asia-Pacific Europe Middle East South Asia UK Business Entertainment Science/Nature Technology Health ------------- Talking Point ------------- Country Profiles In Depth ------------- Programmes ------------- SERVICES Daily E-mail News Ticker Mobile/PDAs ------------- Text Only Feedback Help EDITIONS Change to UK Monday, 29 July, 2002, 11:51 GMT 12:51 UK Asteroid to miss - this time around It has been called the most threatening object in space By Dr David Whitehouse BBC News Online science editor Astronomers have ruled out an Earth impact from asteroid 2002...