when will the world end?

[lushrhian]

is there ever going to be a day where the world ends? or is it going to keep going. But how can it when there is so much pollution?

[theprof]

I've got some doubts about that dawkins.

Leaving aside the chances of the asteroid colliding for a moment, its worth looking at this UK goverment website:

http://www.parliament.uk/post/pn126.pdf

(continued)

[theprof]

The website states a ten metre diameter asteroid moving at up to 25 km per second has the energy of about five times the Hiroshima bomb. Whilst only a relatively small fragment of the 2036 asteroid may collide with the planet, sufficient energy could be released to cause widespread local devastation and/or tsunami.

Admittedly, a global catastrophe seems unlikely, but the risk of local devastation remains sufficiently serious for the world to try to form a think tank in the meantime.

[dawkins]

Very true Prof and I certainly wouldn't want to be underneath it when it hit. But this post is about the world ending and a 300 meter wide rock is not nearly big enough. If the Dinosaurs were killed off by a comet or asteroid it would have been between 6 and 12 miles in diameter. One theory of how the moon formed includes a collision with earth of a Mars sized planetoid. The earth is big enough to take care of itself, us humans on the other hand....

[Gnisy]

define world.

If humans are all dead but there are still other organisms around, is the 'world' at its end or is it still going on?

There plenty of things to die from actually: accidents ( too many cars on the road ), war, consumed chemicals, cancer, diabetes, cardiovascular diseases, snake bites, drug abuse, being stabbed whilst being robbed, being caught in a freak accident.. etcetera, etcetera, etcetera. Pollution's just one way, heck, it's not even a direct cause of death.

It's just me being gloomy. had a bad day.

[Llamatron]

Polution will certainly not put an end to the world. It may well put an end to humanity. But let's face it that wouldn't be a bad thing. How stupid must we be to screw up the only place we have to live on while killing each other because somebody happens to believe something different?

[alvin100]

Dawkins, at 300mtrs in Diameter, what is that chunk of rock likely to weigh? I would have thought that an object that size hitting the earth at thousands of miles per hour would create a fairly devastating shockwave,

[alvin100]

Getting back to the original question, I think (controversialy perhaps) that the best thing for planet earth would be the complete removal of the human race, Get rid of people and the rest of the planet's animals and vegetation could thrive in relative peace and harmony. The human race is like a cancer to the planet. it has no regard for the damage it causes to living things and its surroundings and is ultimately fatal, the best thing to do with a cancer is remove it completely!!

well I did say its a controversial view!!

[qapmoc]

Apophis will make a very close pass by Earth (roughly 37,000 km) on April 13, 2029. The deflection of its trajectory by Earth's gravity at that time will greatly magnify the uncertainty in its orbit, making predictions of a possible future collision with Earth difficult at this time. There are several dates that (as of July 31) have a slight chance of impact. Especially, April 13, 2036, has a probability of impact equal to 0.00012, with lesser probabilities for April 14, 2035, and April 13, 2037 [3]. Since the diameter of Apophis is 320 m, it could cause destruction over a large local area. Apophis will make fairly close passes by Earth (roughly 0.1 AU) in 2013 and 2021 that will allow accurate measurements of its orbit, and easier trajectories to it are available around those times.

[theprof]

Thanks dawkins.

I'm no authority in this field, but the paper I cited in my second link states that the estimated size of the Tunguska aerial explosion in 1908 was between 50 and 100 metres and its mass of the object was around 100,000 tonnes. The energy released was said to be 500-2000 times that of the Hiroshima bomb. The general opinion nowadays is that the explosion was that of an asteroid or comet.

Given that the 2036 asteroid is said to be 300 metres in diameter, extrapolating the above figures results in a truly alarming prospect.

Granted, the devastation would be unlikely to cause the end of the world directly, but it is debatable how many of us would survive the possible nuclear winter that could arise and the consequences of that would be with us for many decades. It is a reasonable assumption that a vast area of the planet would be uninhabitable for a considerable number of years.

I also think we need to define the end of the world. It is all to easy to imagine a huge explosion ripping the earth apart following such an impact in the manner of SF movies.

However, Gnisy makes a valid point in that if all humanity died in the catastrophe, it could be loosely regarded as "the end of the world". The death of all flora and fauna could be viewed from a similar perspective.

Taking this one step further, I wonder how the remaining population would suffer if one of the key economic centres of the world was hit. Could this lead to the collapse of the worldwide financial markets and the monetary system as we know it? How would we cope?

It�s a fascinating thought.