There have been so many predictions regarding the soon coming 'end of the world'. Thankfuly they have all been wrong - so far. But it has set me wondering about the possibility of the world ending because of a collision with another heavenly body. How big would such an object need to be to cause the end of the world? I mean all forms od life permanently ended; the planet broken and the seas scattered. Nothing left that could be identified as being the former 'planet earth?' If there was such a body travelling towards us, how soon would we know it was going to collide with us?

And they will all continue to be wrong. Isn't the problem not only about identifying such a body, but knowing what can be done to stop it?

I predict, sometime in the next 10 billion years, our earth and sun will disappear or transform and evolve, possibly cataclysmically, into nothing, plasma, dust and debris, or something else. Prepare yourselves, the end is nigh...

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Forgiving is Love, Love is For Giving.

Not very big and some. :-)

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Every man has a right to his opinion, but no man has a right to be wrong in his facts. Bernard M. Baruch 1870-1965

Great post, Nancy Lee. Thanks for the investigation.

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In the spring, at the end of the day, you should smell like dirt.--Mar Atwood

Very, very, very big – or of very great mass (an important distinction) and / or velocity. However, relatively super massive objects wazzing around space at increased velocity don't really occur. For the scenario you describe, any object would certainly be 'big' enough to be spotted with even the most basic of equipment or, more importantly, big enough that it's very unlikely to have gone unnoticed; we're talking planet size rather than asteroid. For the scenario you describe, it's unlikely there would be anything we (or even Bruce Willis) could do about it.

Another scenario might be a 'chain reaction' of progressively large objects being knocked out of current orbits, culminating in our collision with a current 'non risk'. Though not impossible, statistically such an event also becomes progressively very unlikely.

On a universal scale asteroids are spread pretty thin; if you flew the Millennium Falcon through an average asteroid belt, even on a random course, there would be a good chance you'd not even see an asteroid – a million miles between each largish asteroid being a rough average. Of course the Earth is significantly bigger than the Falcon, and craters on the moon show strikes are numerous, but compare the 4.5 billion year age of the moon (and lack of atmosphere etc.) with our short time on this rock and the 'end of the world' in our lifetime is again greatly reduced.

End of civilisation as we know it is a different matter. Imagine even a predicted 'significant risk' over a prolonged period, the panic alone could be enough to cripple our fragile infrastructures. Or imagine the effect of even a small scale strike on a vital world economy. I think the most likely solution to the Fermi Paradox is that the 'intelligence' required for interstellar communication is ultimately an evolutionary disadvantage.

There will be future mass extinctions (with a variety of causes), but it's unlikely to be total, all the evidence suggests life of some form will persist on Earth long after we are 'gone', just as it did long before we were 'here'. Over ninety percent of all life that has ever existed on the planet has become extinct. As far as long term survival goes we occupy a very fragile niche, you'd be better off being a single celled organism.

Ultimately our sun has a finite life span, the end is inevitable if not nigh.

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Arguing with a creationist is like playing chess with a pigeon. It'll knock over the pieces, crap on the board, and fly back to it's flock to claim victory.

Apparently, with many people returning despondently to work with raised season ticket prices and an uncertain future today is officially one of the most depressing of the year. Weive coped with this sort of thing before though...

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"Millions long for immortality who don't know what to do with themselves on a rainy Sunday afternoon" Suzanne Ertz

THE END OF THE WORLD

Brenda Lee

Mant thanks almostfreebird. Great song well sung. Great pics.

no i don't believe --------that the world is going to end in the next few years ------i don't trust the mayan calendar----or any dud theories and claims of the world ending

i has been going on since a long time ------different people come out with different dates and all of them turn out false

may be nostradamus has some credibility-------coz i have studied his quatrain's in translations------and the way he has written it in riddles ----just confuses me

the most terrific thing ---i find about nostradamus is that ------he has mentioned that a tall guy with a ''blue turban'' --will be during the time of a big war or something disastrous[ may be a nuclear war]

i am especially fearful-----coz the guy who wears a blue turban all the time ---is our prime minister manmohan singh

Some end of the world links;

http://discovermagazine.com/2000/oct/featworld an old article but some interesting possibilities

http://science.discovery.com/videos/ways-the-world-might-end/ -pardon the adverts

http://www.cracked.com/article_18387_5-ways-world-could-end-youd-never-see-coming.html -some overlap in these- a supervolcano sounds like an unpleasant way to go

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"Millions long for immortality who don't know what to do with themselves on a rainy Sunday afternoon" Suzanne Ertz

There is one sure-fire (pardon the pun) answer:

If a planet-sized object doesn't smash into Earth in the next 4 or 5 billion years, our own sun will do the job when it becomes a red giant.

There is some uncertainty as to whether or not the sun will expand and actually engulf the earth, or merely get so close as to scorch the planet to a cinder.

Either way: total immolation, or scorched till the globe is molten, that ought to do the trick.

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"Be without fear in the face of your enemies. Be brave and upright that God may love thee. Speak the truth always, even if it leads to your death. Safeguard the helpless, and do no wrong". (Knight's Oath, Kingdom of Heaven)

I'm afraid to say, we don't need to wait for any foriegn object to come one day from millions of years, and wipe out the world; we, every other day, are vulnerable to get rid of our own existance. We have prepared enough small objects ourselves to make all it happen.

We couldn't sleep if we really think about the very possible dooms day we harp on daily bases with our own hands and mouth very, very swiftly.

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*It's wonderful to know that all languages are Greek if not understood.*

Quoted not the first time here, thar,
and probably not the last time!
Suited pretty well in this thread.

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I don't know half of you half as well as I should like; and I like less than half of you half as well as you deserve.

If the world does end, I just hope I'm asleep when it happens.

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"Millions long for immortality who don't know what to do with themselves on a rainy Sunday afternoon" Suzanne Ertz

The end of mankind is not the same as the end of the world. That kind of anthropocentric view ignores how truly insignificant we are.

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Arguing with a creationist is like playing chess with a pigeon. It'll knock over the pieces, crap on the board, and fly back to it's flock to claim victory.

If Armageddon is nuclear, then my money is on the cockroaches. Anything more serious and the world goes back to the extremophiles.

They were happily lounging about, when someone started pouring out this toxic pollutant, that caused the greatest extinction in Earth history.

Since then a whole mass of life forms have evolved that live off this foul pollutant.

The Great Oxygenation Event (or, for newspaper headlines, the Oxygen Catastrophe or the Oxygen Crisis) occurred 2.45Ga ago, and nearly annihilated the extremophile bacteria, but they hold on and survive against all the odds.

Maybe sometime, the Earth will be returned to its natural state and this toxic oxygen pollution can be reversed



O2 build-up in the Earth's atmosphere. Red and green lines represent the range of the estimates while time is measured in billions of years ago (Ga).
Stage 1 (3.85–2.45 Ga): Practically no O2 in the atmosphere.
Stage 2 (2.45–1.85 Ga): O2 produced, but absorbed in oceans & seabed rock.
Stage 3 (1.85–0.85 Ga): O2 starts to gas out of the oceans, but is absorbed by land surfaces and formation of ozone layer.
Stages 4 & 5 (0.85–0.54 Ga) & (0.54 Ga–present): O2 sinks filled and the gas accumulates.[1]

everything is relative!
(except some extremophiles, they may not be genetically related to us at all!)

In the wake of some recent news of the possible demise of SETI, perhsps all that will survive is some man made AI forever broadcasting 'Daisy' or similar to the rest of the universe.

I thought they used cockroaches in decommissioned nuclear power plants? A bit cruel if their resistance is poor.

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"Millions long for immortality who don't know what to do with themselves on a rainy Sunday afternoon" Suzanne Ertz