The risk of death via asteroid is higher than dying in an airplane crash – new NEOs are being surveyed as potentially dangerous every day – the time to act is now.
Broad in 91(author and a senior writer at The New York Times. Won two Pulitzer prizes, was a Pulitzer finalist, won the Emmy for PBS Nova, won a Dupont Award, The New York Times, Asteroids, a Menace to Early Life, Could Still Destroy Earth; There's a 'Doomsday Rock,' But When Will It Strike?, June 18, 1991, http://www.nytimes.com/1991/06/18/science/asteroids-menace-early-life-could-still-destroy-earth-there-s-doomsday-rock-but.html?pagewanted-print&src-pm, znf)
"The risk of death," Dr. Chapman continued, "is higher per person than a jet airplane crash. It's more likely than lots of things people worry about, like botulism or fireworks or many carcinogens." The risk is high enough, he said, to suggest the desirability of action. The American Institute of Aeronautics and Astronautics, a society of professional engineers based in Washington, strongly agrees. "We would be derelict if we did nothing," the group said in a position paper last year. Asteroids are craggy remnants from the creation of the solar system that revolve around the Sun, mostly in orbits between those of Mars and Jupiter. Some, however, follow a more eccentric course that takes them across the path of the Earth. So far, 184 Earth-crossing asteroids have been observed and their orbits mapped. New ones are being added at the rate of about two per month. None found so far are expected to hit the Earth soon. On the other hand, it is estimated that only about 10 percent of the big ones have been found so far. Mountains From Space Experts say there are probably 500 Earth-crossing asteroids with diameters of roughly a mile, and perhaps a dozen that are three or more miles wide, making them the size of large mountains. The bigger ones would truly be doomsday rocks. The father of the field is Dr. Eugene M. Shoemaker, a 63-year-old geologist-turned-astronomer with the United States Geological Survey in Flagstaff, Ariz. In the 1950's he closely studied a three-quarters-of-a-mile-wide crater in northern Arizona, which many geologists believed was volcanic in origin. Instead, he proved it was created by a 150-foot-wide asteroid that slammed into the Earth 50,000 years ago. Using a telescope atop Mount Palomar in California, Dr. Shoemaker now heads one of three teams in the United States that hunt for Earth-crossing asteroids. "They're little things" and difficult to spot compared with the stars and planets usually studied by astronomers, he said. "You don't see them unless you use a very large telescope, or unless they come close to the Earth. They're sort of at the threshold of detection." The field has been buttressed by the discovery of numerous asteroid craters around the world that have not yet been totally eroded by the Earth's atmosphere and oceans. If not for these forces, the craters accumulated over the ages would be as prominent as those on the Moon. Dr. Richard Grieve of the Department of Energy, Mines and Resources in Canada compiles a list of confirmed asteroid craters, the total now standing at 131. The list grows by five or six a year. A crater in south Australia is 100 miles across. The largest found so far, measuring 124 miles from rim to rim, is in Ontario.Collisions with Earth have occurred as recently as 1908, when a celestial object exploded near the Stony Tunguska River in Siberia with the force of 12 megatons of TNT. Forests were leveled for dozens of miles around, and horses 400 miles away were reportedly knocked down. Instruments around the world recorded atmospheric shock waves from the blast. Then too, there are near-misses. In 1972 a large asteroid, estimated at up to 260 feet in diameter, or nearly the length of a football field, zipped through the upper atmosphere over the northern United States and Canada, blazing across the sky in a daylight fireball witnessed by thousands of people before it re-entered space. And last January, a small asteroid, perhaps no larger than 30 feet wide, streaked by Earth, within less than half the distance to the Moon.
We’re overdue for our next big asteroid hit—the impact is billions of deaths.Ghayur 7 (A., Lecturer, University Institute of Information Technology, 5/3/2007, NB http://www.aero.org/conferences/planetarydefense/2007papers/P5-1--Ghayur--Paper.pdf)
1694was the year when a man envisioned a bone chilling scenario after witnessing aNear Earth Object (NEO); “What if it would return and hit the Earth?” The man is now a world renowned scientist, Dr. Edmond Halley, and the object now one of the most famous comets, the Halley’s Comet has returned numerous times without any incident. Human civilization has come a long way since the Dark Ages of mid twentieth century, however, it is only now that the mankind is realizing the veracity of the apocalyptic scenario – a heavenly body colliding with earth – the Hellish nightmare which troubled Dr. Halley. Although the chances of Halley’s Comet plummeting into earth are nearly nonexistent, the chances nevertheless of another NEO colliding head on with earth are very much there. The battle-scared face of moon and the numerous impact craters on earth are a living testament to it. But all this evidence proved insufficient to turn any heads until 1994 when Shoemaker-Levy Nine crashed into Jupiter. The earth-sized storms created on Jupiter surface sent alarms through the echelons of bureaucracy and politics and suddenly a nonexistent apocalyptic nightmare had become a very much possible scenario. Today, we are sitting in the midst of ever increasing human population on this planet Earth, which in turn is sitting amidst ever increasing number of identified NEOs. We are already overdue for our next big hit; last one occurring 65 million years ago at Chixilub. Any impact of that scale would result in deaths and displacement of billions, if not more. Do we have a global network and an institution to respond timely and effectively