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It Came From Outer Space!
There is much danger to Earthlings as we tiptoe through eternity.Click thumbnail to view full-size
Asteroid impact. No defense possible
We were treated to a spectacular event in our skies over England and Ireland last night.
For once, it was a clear night suffused with the heavenly firmament, as it is poetically know, of stars and planets as the Milky Way and all the other players shone forth, as they do all the time but we rarely see them.
Arriving from the east and heading west came at first a “large” object and as it segued into our outer atmosphere, began to turn white hot and then break up into many smaller “meteors.” Watchers who knew a bit about the debris which bombards the planet constantly were divided as to whether they were watching the break-up of a meteor in the shape of a piece of rock, or some man-made space junk, such as a satellite.
There was speculation on the speed of the immigrant. “That’s going at the speed of military aircraft,” announced one observer.
Wiser heads knew no military craft could reach the speeds of the incoming: 18 miles above the surface of our world, astronomers told us today, the speed initially of the meteorites - if this is what they were - was around 18,000 miles per hour - and could have been much faster than that.
Space debris like this burns up by the hundreds of tons every year in Earth’s atmosphere. Without this thin yet vital cushion of air, we would be like ducks in a shooting gallery and might well have to live underground or undersea.
It is no mystery to most of us today that the high speed of the space rocks and the friction from the air molecules produces this blinding and destructive heat and destruction of the potential missiles before they can impact with the surface and cause death and destruction. The fact that most are small does not detract from the kinetic energy they store at this great speed and a piece the size of a bullet would impact with explosive force and could destroy a large area.
Many of these potential visitors are strays from the Asteroid Belt, that area between Mars and Jupiter where they are held in check by the gravity of their huge neighbors. We also have “Near Earth” asteroids and Trojans, etc, other areas of space where asteroids gather.
We have been watching and plotting the movements of asteroids for years as our history has shown several destructive impacts from much larger bodies over the millennia. These take roughly two forms: a direct impact with earth causing a life-threatening chain of events as material is thrown into the atmosphere, even changing the climate for many years and causing the loss of species.
Recently, another type of collision with the planet has been noted called “Air Burst” impact. These events are caused by significantly smaller asteroids which overheat and “explode” just above the surface of the planet. Space rocks no more than several meteors across can cause hundreds of miles of destruction to flora and fauna - and man if he’s somewhere underneath. We have clear evidence of one that struck Siberia about 100 years ago showing many square miles of downed trees from the blast wave.
There are asteroids up there much larger than this…a few many KILOMETERS across! One is so large, it is classified as a minor planet! If one of these monsters would collide with earth it would destroy most if not all life and might even structurally damage the planet and cause it to break up. It would be a spectacular event, but there would be no posterity to see the records.
The worry among astrophysicists and their ilk is that these monsters travel so darned fast there can be little warning of their arrival. And even if we could forecast their arrival a year ahead, what could we do? In the event that the incoming was not huge, maybe we could evacuate the area…maybe! Look what happened to New Orleans when the hurricane struck, evacuation proved about hopeless.
If on our journey through space, we stumbled into the orbit of giant asteroids Ceres, Pallas, or Vesta, all more than 500 kilometers across, or into the path of another 150, plus monsters, all more than 100 kilometers wide, well, time to bend down and kiss the patootie adios!
Not that it would need be one of these space giants; an asteroid a couple of miles wide would probably give all life as we know it the death blow - as one did the dinosaurs and those that caused the other three great extinctions of Planet Earth.
But what a sight it would be for doomed earthlings!! As the huge rock hit our atmosphere, it would begin to glow and then get white hot. Thousands of chunks would burn off the surface and join the charge towards the surface of Mother earth. We would only have seconds to live then as the speed of approach might exceed 50,000 miles per hour with just 18 miles to cover. As the remains impacted with the planet, an explosion of dimensions never before seen of imagined would occur. For perhaps a thousand miles in every direction, the destruction would be total, even mountains would be leveled. Then a huge cloud of ash and particulate matter would plunge us into a permanent night which could last for a hundred years. Nothing and no one could survive unless we had left for the moon or a nearby planet, should our technology be up to escaping like this…and this would only be for a few, and you know who they would be! Not you and I! Obama, Cameron, Richard Branson and the “royals” would watch the disaster from a safe distance, along with the crown jewels. Kate and Willy might have smug smiles watching the end of the paparazzi!…