Near Earth Asteroid March 5th

DesVegas

Hold onto your hats!!

http://www.msn.com/en-gb/news/world/100-foot-asteroid-to-buzz-earth-next-month/ar-BBp9zVo?li=BBoPOOl?ocid=binganswers

seany65

I don't want to p*ss on anybody's chips, but as far as I'm concerned, these odds they quote about the chances of it hitting earth either this time or the next two times mean nothing. Remember, 'They' said the Titanic couldn't sink.

sinbaadi

They should be testing targeting systems on objects like this.

57Deluxe

I often get a scare from a near-earth Hemorrhoid...

ICBM

seany65 said:

I don't want to p*ss on anybody's chips, but as far as I'm concerned, these odds they quote about the chances of it hitting earth either this time or the next two times mean nothing. Remember, 'They' said the Titanic couldn't sink.

The ship's designers didn't - that was a media invention.

This rock is not going to hit the Earth now, or next time, or the one after that. The difficulty is working out what happens in the long run, because every time it comes close its orbit is altered by the Earth's gravity, and how much depends on how far away it is - so an error now quickly makes the result after a couple of iterations very difficult to calculate.

This is not a dinosaur-extinction size rock either - it's only a bit bigger than the 2013 Chelyabinsk meteor. That could still be bad enough though - the reason that only caused minor damage and injuries at ground level was because it came in at a very shallow angle so it exploded high in the atmosphere and only the shock wave and small fragments reached the ground.

The Barringer Crater in Arizona was made by an only slightly larger one that came in almost vertically - that produced an explosion of about 10 megatons and a hole in the ground a mile wide. If that happened in a populated area now it could kill millions.

hugbot

seany65;961523" said:

I don't want to p*ss on anybody's chips, but as far as I'm concerned, these odds they quote about the chances of it hitting earth either this time or the next two times mean nothing. Remember, 'They' said the Titanic couldn't sink.

Who, astronomers? I didn't know they worked on the titanic.

GuitarMonkey

Bring it on I say.

Bogwhoppit

ICBM said:

The Barringer Crater in Arizona was made by an only slightly larger one that came in almost vertically - that produced an explosion of about 10 megatons and a hole in the ground a mile wide. If that happened in a populated area now it could kill millions.

Ideally, we require small one that lands on parliament on a Wednesday at around 12 (ish)....

Chalky

Bogwhoppit;961707" said:

ICBM said:

The Barringer Crater in Arizona was made by an only slightly larger one that came in almost vertically - that produced an explosion of about 10 megatons and a hole in the ground a mile wide. If that happened in a populated area now it could kill millions.





Ideally, we require small one that lands on parliament on a Wednesday at around 12 (ish)....

Very small odds of it hitting any densely populated area. Remember the majority of Earth's surface is not populated at all and a further large fraction is sparsely populated.

ICBM

Chalky said:

Very small odds of it hitting any densely populated area. Remember the majority of Earth's surface is not populated at all and a further large fraction is sparsely populated.

70% is ocean to start with. A small asteroid like these ones wouldn't cause any permanent damage at all if it falls into the sea. Even to cause a tsunami that would affect a large area of coastline would need a bigger one, very close to the shore.

Chalky

ICBM;961873" said:

Chalky said:Very small odds of it hitting any densely populated area. Remember the majority of Earth's surface is not populated at all and a further large fraction is sparsely populated.





70% is ocean to start with. A small asteroid like these ones wouldn't cause any permanent damage at all if it falls into the sea. Even to cause a tsunami that would affect a large area of coastline would need a bigger one, very close to the shore.

Even then there would probably not be a tsunami - the kinetic energy converts to heat that vaporises the seawater and moves upwards rather than outwards (path of least resistance). In the following moments the 'hole' left by the vaporisation will simply pull surrounding water back inwards by gravity. An expansion followed by a contraction.

In the numerous multi-megaton tests in the South Pacific, the result was a large ripple or wave of a metre or more high and several metres along its direction. Whereas what we think of now as a tsunami is a large body of water several metres high and kilometres along its direction.

ICBM

Chalky said:

Even then there would probably not be a tsunami - the kinetic energy converts to heat that vaporises the seawater and moves upwards rather than outwards (path of least resistance). In the following moments the 'hole' left by the vaporisation will simply pull surrounding water back inwards by gravity. An expansion followed by a contraction.

In the numerous multi-megaton tests in the South Pacific, the result was a large ripple or wave of a metre or more high and several metres along its direction. Whereas what we think of now as a tsunami is a large body of water several metres high and kilometres along its direction.

Yes - you do get that if the asteroid is large enough though... admittedly orders of magnitude bigger.

These rocks are tiny even by small-asteroid standards. The one that wiped out the dinosaurs was roughly ten kilometers across - almost a thousand times larger, ie a billion times heavier - and that did cause a mega-tsunami. I'm not sure where the threshold is, but I'm pretty sure it would be a much bigger rock than these little ones.

Chalky

Still not convinced we'd get a mega-tsunami. In the only practical scientific experienced-based evidence we have, the results are that when very high energy levels are created explosively - many by the US up to 15 mt and the Russians up to 50 mt - then the energy finds the most efficient gradient for dissipation and follows that. Hence most goes upwards. Even the shockwaves largely bounce off the ground.

When the US used to 'vaporise' coral islands at sea level, they were somewhat crestfallen to see that the crater allegedly a mile wide was also impressively shallow despite detonating the device on the ground. It is often viewed as counter-intuitive that energy behaves like this and its not helpful to the various movies that wish to show the depth or width of the propagation of energy. But it is one of the reasons why development of larger nuclear weapons was stalled. Despite its optimum height airburst the 1962 Russian 50mt bomb did impressively little damage for something many times bigger than the combined power of every explosive used in every war since time began. Warmed up a lot of air high in.the atmosphere though!

ICBM

Chalky said:

Still not convinced we'd get a mega-tsunami. In the only practical scientific experienced-based evidence we have, the results are that when very high energy levels are created explosively - many by the US up to 15 mt and the Russians up to 50 mt - then the energy finds the most efficient gradient for dissipation and follows that. Hence most goes upwards. Even the shockwaves largely bounce off the ground.

These are so far below the energy levels of a larger asteroid impact that it's irrelevant though. The dinosaur-killing one caused a mega-tsunami that went hundreds of kilometers inland over what is now North America. The question is at what point does the upward energy direction give way to sideways expansion.

Chalky said:

When the US used to 'vaporise' coral islands at sea level, they were somewhat crestfallen to see that the crater allegedly a mile wide was also impressively shallow despite detonating the device on the ground. It is often viewed as counter-intuitive that energy behaves like this and its not helpful to the various movies that wish to show the depth or width of the propagation of energy.

The Barringer Crater is over 500ft deep though - into solid rock - and the explosive equivalent of that is only estimated at around 10 megatons. There appears to be something different about the dynamics of a direct impact as opposed to an explosion at ground level or an air burst (nuclear or natural).

Bogwhoppit

Chalky said:

Still not convinced we'd get a mega-tsunami.

I hope not, that stuff tastes horrible - especially on Rye.

Reverend

ICBM said:

Chalky said:

Very small odds of it hitting any densely populated area. Remember the majority of Earth's surface is not populated at all and a further large fraction is sparsely populated.

70% is ocean to start with. A small asteroid like these ones wouldn't cause any permanent damage at all if it falls into the sea. Even to cause a tsunami that would affect a large area of coastline would need a bigger one, very close to the shore.

It would if it hit your boat.

chillidoggy

Any chance it could hit Brussels? Just thinking it might solve a few issues.

thecolourbox

Maybe it's a Near-Asteroid Earth that we exist upon

Chalky

Man, that's deep y'know.

Old hippies joke:
Where's the exit?
Over there!
Aw, way out!

Sambostar

Watch out for a surge of ginger children being born on the 6th.

Bellycaster

chillidoggy;962408" said:

Any chance it could hit Brussels? Just thinking it might solve a few issues.

Look, if you hate Sprouts that much, don't eat the bloody things.