Dynamic, Important New Information, How We Shall Deal with Apophis!

As a boy my day was incomplete if I didn't spend at least a few hours in the dark recesses of the public library, hunting through stacks of Science Fiction - novels and shorts - for something I had yet to read. Heinlein, Asimov, Bradbury - so many more, the list goes on. Now that they tell us our favorite planets are gas, there's not much to look forward to. But still, there is real science!

So, on that fateful summer morning in the year 2002, when those distracting little words that march across the bottom of ones TV screen during newscasts strolled similarly across mine - the heralds of future doom - I could hardly fail to notice; they made mention of a collision-course asteroid, coming in the years ahead! Young and romantic, in a lab-coat kind of a way, I jotted down the date for the world's end, and created a poster for my bedroom door: "The World Will End on Friday, the 13th of April, in 2029!" I kept an eye on the TV screen, but oddly, the asteroid report vanished; there was not another word. Only the poster remained.

The coming devastation remained unreported until a televised 20/20 Special Presentation called "Final Days" aired in 2006, four years after the aforementioned blip. The program many will recall dealt with several ways in which the world might suddenly end. Gamma Ray Bursts, giant evil robots, and yes, the asteroid which had now been deemed "Apophis", which translates from the Greek as "the Uncreator", a "serpent that dwells in eternal darkness". Apophis - formerly known as 2002NY40 - the broadcasters said, was a "near miss" on August 17th and 18th of 2006. They went on to say the space wanderer is again due in 2029 (Friday, April 13), and will pass much closer than the August 2006 pass, "within the orbits of our communication satellites". That same asteroid will again pass, even closer, on April 13, 2036. Now excuse me, but "within the orbits of our communication satellites" does indeed give me pause!

They said because of the speed of the asteroid, at 65,000 kilometers per hour, there was little hope of interception. They said, in any case, if we explode the traveler, we will be confronted not with one large object, but with hundreds, or thousands of smaller objects. NASA said then that the approach of the 460 foot long asteroid in 2029 was "not dangerous". They went on to say that they were very concerned by the unpredictability of the orbital change and the potential for impact in 2036.

Popular Science Magazine published an article reporting that the United States, and China are those most likely to feel the devastation of Apophis impact. Several ways of dealing with Apophis have been proposed. The History Channel recently mentioned the possibility of focusing sunlight on the invader. But they haven't actually tried it on a real asteroid. Some scientists have suggested we might give Apophis a gentle nudge while it is still far away, so it will miss the Earth cleanly. This nudge would be delivered by a volley of up to six nuclear missiles packing 1.2 megaton B83 warheads. This is consistent with the reported current thinking of Russian Scientists. These would detonate a hundred meters or so from the asteroid, and the heat of the explosions would cause part of Apophis to vaporize and move the remainder to one side. One science fiction reminiscent solution considered landing on the asteroid, drilling well below the surface, and planting an explosive device. That particular plan pales in comparison to what the Space Administration is in fact considering!

I promised some great new information and speculation and here it comes. We have established that Apophis wii come close to the Earth in April of 2029. Close meaning, within the orbits of our communication satellites. During that bypass, the asteroid's orbit will be altered by our gravitational pull, so that the following passage, in 2036, will be closer - by an indeterminate amount. NASA with out much fanfare has gone to great lengths to determine the range of the change in orbit, and to determine if there is a likelihood of impact. NASA stipulates several factors which come into involvement. Factors include the gravity of the Sun, Moon, other planets, as well as the three largest asteroids. Additional factors can influence the asteroids course in ways that depend on rarely known details, including the mass, and spin of the asteroid, how Apophis absorbs and reflects sunlight, and even the asteroids interaction with other asteroids, beyond the three largest.These small uncertainties can cause up to 23 Earth radii of prediction error for Apophis by 2036.

Apparently NASA has some plans to deal with the threat!

Here is what they say:

"....scaling up to distribute 250 kg (550 pounds) of a reflective or absorptive material (similar to the carbon fiber mesh being considered for solar sails) across the surface could use the existing radiation forces to produce a 6-sigma trajectory change, moving at least "99.9999998" percent of the statistically possible trajectories away from the Earth in just 18 years.

And:

"..the team found small variations in the energy absorption and reflection properties of Apophis' surface are sufficient to cause enough trajectory change to obscure the difference between an impact and a miss in 2036. Changing the amount of energy Apophis absorbs by half a percent as late as 2018 - for example by covering a 40 x 40 meter (130 x 130 foot) patch with lightweight reflective materials (an 8 kg payload) - can change its position in 2036 by a minimum of one Earth radius"
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It would appear that NASA is seriously considering a coat of fiber mesh for the incoming projectile

An Earth Radii is 3963 miles. 23 Earth Radii is 84,870 miles. So the range of potential trajectories is nearly 85,000 miles. Wikipedia says a "Low Earth Orbit Satellite" is about 250 miles above the planet.
In any case, the NASA link clearly says there is an absolute need for intervention; they have a plan to cover Apophis with absorptive/reflective material, which will provide about 99.9 % assurance of no impact.

That's how I read it.