manalishi:
I read recently that the cosmos is practically a junk yard,with millions of debris pieces hurling around at 17,000 mph,mostly from defunct satellites.There’s even a NASA astronauts gauntlet floating about from a circa 1960s mission that he apparently ‘misplaced’’I wonder how much of that debris makes it’s way earthwards,mistaken as a meteor?..I did witness a colossal,thingy,over Staffordshire way mid nineties.Once seen never forgotten.Project-Bluebeam anyone?
“Fireballs” those meteors that range in size from a fist to a car - are fairly common. They are easier to see, as they take a few seconds to cross the entire sky, compared to a “blink-and-you-miss-it” appearance for regular meteors, that have burned out, totally vapourized in the high atmosphere in less than a second.
On the subjects of “Meteors” and “Meteorites”, as a general rule of thumb, the vast majority of “random space projectiles” are moving at around 10miles per second when they hit the atmosphere, the friction in slowing down suddenly from air resistances - being the thing that causes such objects to burn up.
Most of these projectiles range in size from a breadcrumb to a golf ball in size. These form 99% of all meteors seen streaking across our skies at different times of the years as the “regular” meteor showers.
They are the remains of long-since broken up comets these “small pieces”. There’s just not enough material of them to make it through the Atmosphere to leave anything solid on the ground as a “Meteorite”. They are entirely vapourized at an altitude far exceeding any aircraft down below them, so don’t present a danger to such aircraft. If they did we would see Airport Lockdowns when every regular meteor shower happens - if you think about it…
Less often, you get some spectacular meteors in the forms of “storms” such as the Leonids in mid-november every year… Most of the time, you might see upto 100 per hour on “shower night”. BUT every 33 years or so, the Earth’s Orbit takes it right through the nucleus of this orbiting material, and we end up with a “storm” instead of a “regular shower”. The last time I saw the Leonids do this was November 1998, so I guess the next one will be due around 2031. “Day of the Triffids” quality we’re talking about here btw.
Once “space debris” is upto the size of a boulder to around the size of a house - we’re talking about “fireball” re-entry, and enough material survives to strike the ground as a “Meteorite”. These objects are usually rich in Iron and Nickel.
Once any material remains to actually impact the Earth’s surface, then it is inevitable that there will be some collateral damage to the surrounding region, even if that damage is limited to broken windows, knocked-down trees, etc.
The really large ones, a mile or more across - hit the ground hard enough to cause a cataclysm in the surrounding environment.
Tunguska, Russia 1908 was probably the last one recorded of THIS magnitude.
The world is however littered with such “event evidence” over geological time.