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Death 'star' approaches
The 28-year countdown clock has started and it may be ticking away the seconds of life remaining to unsuspecting millions.
That's the worry some anguished scientists have as recent study of near-Earth objects has confirmed that asteroid 011 AG5 has a high possibility of striking Earth a deadly blow in 2040.
Calles for a "Situational Awareness system" have become more strident to the point where some Russian scientists have gone on record demanding an Earth defense network be established among space-capable nations immediately.
Photograph of region where asteroid 2011 AG5 was discovered
Ferevent discussions about the latest asteroid threat to Earth dominated the Vienna conference of the 49th session of the Scientific and Technical Subcommittee of the United Nations Committee on the Peaceful Uses of Outer Space.
Target: Earth
A window that an asteroid must pass through in orbits previous to an impact event is called a "keyhole." Several keyholes exist for three other asteroids besides 2011 AG5. One of those asteroids is a continent killer, the other two—like 2011 AG5—are city killers.
Despite Russian scientist's mounting concern, NASA's JPL Near-Earth Object (NEO) Observations Program chief, Donald Yeomans of NASA's, played down the probability of an impact. Yeomans told Leonard David of SPACE.com that "Although this keyhole is considerably larger than the Apophis keyhole in 2029, it would still be a straightforward task to alter the asteroid’s trajectory enough to miss the keyhole—and hence the impact in 2040."
The scientist's reference to to the extremely dangerous asteroid, Apophis, is one that Russian astrophysicists believe will impact Earth in either 2029 or 2036. NASA dismisses their concern.
Apophis is the Greek name for the ancient Egyptian demongod Apep, also called the Uncreator.
"The prudent course of action," Yeomans added, "is then to wait at least until the 2013 observations are processed before making any preliminary plans for a potential deflection mission."
Ocean strike could be devastating
If 2011 AG5 hits the ocean, an incredible tsunami as big as 1,000 feet high traveling at near supersonic speeds would devastate coastlines of continents. Within hours, millions could die.
The economy of the entire world would suffer. Most nations would be plunges into deep recessions within weeks.
Coastal regions would be inundated
Global commerce would slow to a snail's pace and violent storms could whip the planet for months.
A land impact would not have such widespread devastation, but depending on the region hit the destruction could be horrific.
City annihilated 'like nuclear blast'
A major city hit by 2011 AG5 would be annihilated. Most buildings and people would be instantly vaporized. The kinetic force of the strike would convert to pure energy within milliseconds and detonate with a force as great as a multi-megaton nuclear bomb—much worse than the Hiroshima or Nagasaki bombs dropped in Japan.
People running for their lives as asteroid approaches
Evacuation of a city would be nearly impossible as the impact could not be calculated with accuracy until mere hours before the event. When the impact occurred it would be one of the greatest human calamaties in history.
Evacuating a major city would be nearly impossible
Shock waves radiating from the epicenter would race through the atmosphere and the ground.
Asteroid impact would set off raging 'fire hurricanes'
Massive firestorms, earthquakes, catastrophic environmental destruction as far as one hundred miles away with fierce fire hurricanes approaching speeds of hundreds of miles per hour.
Other asteroid threats now converging
Three other huge asteroids are barreling through space on a rendezvous with Earth. Because of their speed and mass a few could release the energy of 100s of thermonuclear bombs.
Asteroid tracking programs of NEOs are still an inexact science. Some astronomers admit if one of the really big NEOs blindsides us and approaches from behind the sun, on a collision trajectory with Earth, by the time the thing's discovered only weeks will remain to stop it.
Of course, with so little time remaining nothing could be done except to make final arrangements for the end of the world and the abrupt passing of the human race.
Tens of thousands of asteroids and comets haunt the space ways, some changing their orbits every time they pass near a large gravitational field like one of the outer gas giants or swing close by the sun. Their orbits are often changeable and unpredictable.
Those marked as hazardous to the health of the human race are tagged as Potentially Hazardous Asteroids (PHA).
Many PHAs exist—completely unknown and invisible. Some of those could be larger than Pluto.
What's really frightening is no one knows where they are, how many exist or when they might show up unannounced.
What is known? Other than 2011 AG5, three other PHAs are heading towards Earth. At this moment we have no technology to stop them.
Threat number one
Asteroid 2002 NT7 arrives February 1, 2019: This continent killer is 1.5 miles long. It's been called by some observers the most threatening asteroid ever detected.
Initial calculations of its preliminary orbit reveals it's on a collision course with Earth. Although the permutations of its orbit could change, nothing is certain in this game of cosmic billiards.
When it was discovered, astronomers assigned the killer a threat rating of +0.06. That rating on the Palermo technical scale—a risk assessment of asteroid and comet impact with Earth—awards NT7 the dubious distinction of being the first asteroid ever to be given a positive value.
Positive for the asteroid, a big, big negative for Earth. It's size and speed are calculated as meeting the threshold needed to vaporize an entire continent.
The asteroid's orbit takes 837 days traveling from the distance of the Martian orbit to just within the Earth's orbit.
As of this writing, it's due to meet up with Earth in less than 8 short years.
Will it hit? Although the likelihood's shrinking, it's still possible.
Threat number two
Asteroid Apophis arrives 2036: It's a potential city killer like 2011 AG5. Apophis is 1,000 feet across.
Approximately the size of the asteroid that exploded in the sky above the Siberian Tunguska forest during 1908, Apophis exceddingly dangerous. London, Moscow or New York could be vaporized by it.
Russian scientists are convinced that Apophis is going to hit Earth in 2036. NASA says no.
But the Russians think NASA's wrong and called major conferences to address the problem of Apophis and other PHAs like NT7. The Russians are hoping that the European Space Agency will work with them to develop a program to intercept PHAs and steer them away from Earth while there's still time.
The alternative, they argue, is almost too frightening to contemplate: millions dead, the Earth's climate destroyed, or the planet itself wiped out with mass extinction.
Although Apophis cannot cause the end of life on Earth it can cause the biggest disaster in history. Impact on land would be bad enough. If it hits a body of water—the Atlantic Ocean for example—the titanic energy released will generate a supersonic tsunami a thousand feet high.
If it impacted the north Atlantic much of the East Coast of the U.S. could be destroyed. To the east, the UK and coastline of Northern Europe would be swept away.
Will it hit? Although NASA says it's unlikely, the Russians insist it probably will impact.
Threat number three
Asteroid 1999 RQ36 arrives 2082. It's another big city killer being 1,837 feet across.
According to Maria Eugenia Sansaturio and astronomers from the Universidad de Valladolid in Spain, asteroid 1999 RQ36 has two very good chances to hit Earth during the year 2082.
Sansaturio and her colleagues are shocked. Until recently they thought the asteroid would miss Earth by a wide margin on both of the approaches during 2082.
Will it hit? The latest calculations increase the odds it will.
The world killers
Nothing yet has been tracked in the solar system that's the size of the deadly asteroid that created the Chicxulub crater in Mexico and wiped out the dinosaurs.
Yet that doesn't mean that someone, somewhere might not spot a giant PHA tomorrow—or the day after that—a leviathan tumbling through space that has the name "Earth" written across it like a gigantic tombstone.
Russians demand Earth asteroid deflection program now
Ever since the the Russian news agency, Ria Novosti, reported that Russian space scientists are very concerned over the prospects of asteroid Apophis striking Earth, much talk has erupted in some European scientific circles over the likelihood of such a disaster happening any time in the foreseeable future.
While the Russians insist the odds are high that the 1,000-foot rock will slam into the Earth—perhaps taking out a whole city of millions when it hits—the U.S. space agency NASA argues their figures show only a one in 250,000 chance of such a calamity occurring.
Yet the lead astronomer in the Russian group that met in a July 2011 conference concerning the asteroid threat to Earth, Professor Leonid Sokolov of the St. Petersburg State University, stated what NASA already knows: sooner or later one of those tumbling space rocks will hit Earth. When it does only its mass and speed will determine how much damage it will cause.
The Russians want a unified asteroid deflection program that's well funded and equipped. They believe that someday it may mean the difference between the survival of the human race or its extinction.
The dinosaurs—the most successful species ever to walk the Earth—had 200 million years to build an asteroid deflection program. They failed to evolve quickly enough and the universe wiped them out.
The human race has only been around about one percent of the time the dinosaurs had, but humans have evolved much faster. Hopefully, that evolution includes enough intelligence to accomplish what the dinosaurs were unable to do: protect the species from the dangers that roam Earth's backyard.
Time growing short
As the months progressed towards the asteroid summit chaired by the Russians, other astrophysicists and astronomers are added their thoughts.
Daniele Farigon a physicist at the Farigon of the University of Rome, proposes using nuclear powered mass-driver rockets to steer the space rock anywhere desperate Earth folk wanted it to go. She doesn't say exactly where the asteroid or comet should be ferried to…perhaps into the sun? It couldn't do any harm there.
Other visionaries have other visions. Some want to attach giant solar sails or change asteroid and comet orbits using gentle nudges. Everyone agrees that trying to blow it up with an atom bomb would be a very bad idea, Bruce Willis and Armageddon notwithstanding.
Russians meeting on asteroid dangers
At the conference, the European Commission considered Roscosmos's proposal to create a joint agency specifically tasked to establish a workable asteroid deflection program.
When asked if the idea really smacked of science fiction, Anatoly Perminov, the head of the Russian Federal Space Agency Roscosm, responded, “People’s lives are at stake. We should pay several hundred million dollars and build a system that would allow us to prevent a collision, rather than sit and wait for it to happen and kill hundreds of thousands of people.”
In the meantime, four clocks are now counting down towards the keyholes of four asteroids. Time grows shorter.
Posted: 02/28/12 07:28 PM ET | Updated: 02/29/12 06:00 AM ET