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Last Update: 4-19-2008 Impact threat reduced. Apophis may not be a problem as first thought. Scroll down the page for News
Articles Note: We are not in any immediate danger from an asteroid impact, at least not that we know of at this time, but 30 years from now looks questionable. In the grand scheme of things, 30 years is no time at all. Asteroid Apophis (Greek for the Egyptian god, meaning destroyer), number 99942, first identified in 2004 and designated 2004 MN4, was recently predicted to pass by Earth in April 2013 and 2021, extremely close to Earth in April 2029, (within approximately 15,000 miles), and possibly impact Earth in April 2035 or 2036. Dedicated evaluation is in progress, and will be for many years to come, studying its orbit to make more refined estimates in the years ahead. But this is far from the end of the story. Due to its "smaller" size (estimated to be close to 330 meters, or 1,000 feet across) and current extreme distance from Earth, it is not possible at this time to determine exactly what Apophis looks like, what it is made of and what its precise orbital course will be by 2029 and later years. It could be a single object of solid rock or metal, or loose rock, or several objects of solid or loose material. The serious concern is that if Apophis passes through a resonance (gravitational) "keyhole" close to Earth in 2029, which is an area approximately 2,000 feet across and about 18,700 miles from Earth, its orbit could be affected just enough (tugged) by Earth's gravity to change its course for a possible impact with Earth in 2035 or 2036. There are many variables to analyze in the years ahead. Predictions are far from exact at this time. It is TIME that is the critical element for us. Time to determine Apophis' precise orbital path and, more importantly, what may be needed, and can be prepared, in the way of deflection space missions, hopefully occurring many years before 2035. After all, it generally takes many months or years for spacecraft to reach an object. And, it may take more than one attempt to deflect. Complete destruction of such an object using a massive explosive charge is generally considered not to be possible, so deflection is the best and cleaner bet. Mankind has never attempted to deflect an asteroid or comet, so a great deal of design and possible advance demonstration missions will be required. A serious recommendation was recently submitted to the U.S. government to send a spacecraft to Apophis by 2013 to land a transponder on it to be used to monitor its precise path, providing much needed time to evaluate its course, perform risk assessments and develop protection plans. NASA already has some experience, having orbited and landed on asteroid Eros with the NEAR mission, and impacted on comet Tempel 1 with the Deep Impact mission. We now have, or are close to having, the necessary technology and ability to slightly deflect (or nudge) an object from its present course, but since we have never done it, we must learn by doing. This is definitely something that you don't want to depend totally on only having just one chance to be successful. Regarding "larger" asteroids, it is estimated that the impact of an object 1 kilometer across (3,300 feet) would be globally devastating on Earth's atmosphere and all human life. Such an impact would be on the order of 70,000 megatons of TNT, which is HUGE, the equivalent of 1,400 of the largest thermonuclear weapons ever detonated, most likely being a global life-extinction event. Some asteroids already located are a couple hundred miles across, but none have been identified as potential Earth-impacting objects (at least not yet). Much smaller asteroids, 100 to 200 meters in size, are far more numerous in the solar system, posing the biggest threat to Earth, much sooner over time. They are truly "stealth" objects due to their small size, being very difficult to detect since we have so few properly developed observatories watching for them. We must watch for these asteroids very closely, as they can do extreme localized damage, destroying large cities. Take a look at the Meteor (Barringer) Crater in Arizona, to witness what a "very tiny" asteroid, or meteor (solid metal), can do, powerful enough to have destroyed New York City and surrounding area (artist's rendering for perspective , but also realize the incredible blast energy that would be generated, aside from the crater). Absolutely astounding. All it takes is just one such devastating impact, killing millions of people in a matter of hours, for the world to fully understand the immensity of what we are up against. Presently, no nation, including the United States, is adequately equipped to search for these smaller asteroids, which many times have passed very close to Earth, taking us by surprise. This is truly an enormous international concern having an incredibly complex amount of political hurdles to overcome in developing Earth-wide protection plans. Right now NASA and the European Space Agency (ESA) are the only organizations that are "starting" to develop programs to watch for and deflect asteroids. But they are in their infancy, having a long way to go before being properly prepared. The biggest limiting factors are apprehensive, unsupportive governments and inadequate funding. The impact from something the size of "small" Apophis, about 1,000 feet across having the energy of approximately 800 to 1,000 megatons of TNT, would not be a global life-extinction event, but, depending on its physical composition, where it hits Earth and at what angle, it could do widespread catastrophic damage, far, far greater than anything mankind has ever witnessed and experienced in recorded history, destroying cities and devastating thousands of square miles. Or, if it hits the ocean, could generate a devastating tidal wave, destroying many coastal cities and millions of people in its path. Rough estimates have indicated a band or path of possible impact that includes Europe and the Middle East, but it also identifies a possible impact in the Pacific Ocean. It is impossible to accurately predict at this point in time. A potential impact by Apophis is no small matter to dismiss. This is extremely serious, life-threatening business, possibly affecting tens of millions of people in the blink of an eye. Earthlings have never faced such a potential catastrophic event, so a great deal of communication, education, cooperation and funding will be necessary as time progresses, depending on what the results of our on-going evaluations indicate. We must pay very close attention to this object, as well as continue, and expand, programs to watch for other such Near Earth Objects (NEOs). The survival of civilization will literally depend on it. It is not a matter of IF, but WHEN a sizable destructive object from space will target our tiny, precious planet. The clock is now ticking loudly. Time is of the essence! Asteroid Apophis is the first significant object on our long-range radar screen that is looking squarely at visiting Earth, possibly VERY up-close-and-personal. But we certainly cannot afford a direct visit. Fortunately, it is affording us some time to analyze and prepare, if we use the time wisely and productively. Governments need to "get the lead out" and open the funding door widely to support NEO detection and protection programs. NEO and Asteroid Websites
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