Do we have any protection from giant asteroids, which could wipe out all life on Earth in a flash?
921191
Only early detection.  The most promising idea of how to divert such an asteroid would involve sending a probe out to it that would be massive enough to pull at it by way of its own gravity.  If this is done with enough time to spare, you could actually divert the path of the asteroid so that it misses earth altogether.
893208
Our star, the Sun (Sol), is a G-2 class star.  Eventually it will deplete its hydrogen (H), converting into a helium (He) cooler burning star.  When this occurs it will be a cosmocataclysmic and extinction level event as far as the Earth is concerned, for the Sun will hyperdialate 100 times its mass into a Red Giant Star, engulfing the orbit of the Earth.  This event will generate a spontaneous stellar radiation burst, frying half of each planet, and generating a powerful shock wave causing atmospheric violence and may even dislodge planets out of their orbits to realign in new orbits around the Red Giant.  Hence, because the orbits of the planets are not stationary, the Earth most likely will survive when the initial shock wave hits our planet, perturbing its orbit away from the expanding stellar mass, but still it will precipitate an extinction level event that will lay down a new Carboniferous Layer to the Geological Column.\n\nNext, after about one million years our Red Giant will deplete its helium, and due to its enormous mass gravity will cause the star to collapse, thus “crunching” and compressing its internal molecular structure into a White Dwarf Star, while it simultaneously explodes its outer shell, the photosphere, in a sudden catastrophic multi-shock wave event called a “Nebula Discontinuity Event”, or merely a “Nebula”.  This will simultaneously create a Local Compression Bubble around our region of the Galaxy.  Only larger Red Supergiants, not smaller Red Giants, undergo a supernova event and become Neutron Stars or Black Holes.  The new White Dwarf will have the mass equal to the size of the Earth, yet it will retain the electromagnetic field of its original G-2 class star phase.  The nebula event will most likely incinerate the planets with X-ray radiation causing sterilization on Earth, generating another extinction level event.  The shock waves will concentrically disperse the planets outwardly from the smaller cool burning White Dwarf, and Earth will become a dead frozen planet.
96388
No. But there will be one that comes pretty damn close. If you use a search engine like Yahoo! you can find out about the near miss that happend not too long ago (I think around November 1998). It was never on the news for good reason.  But we had a close call that could have wiped us all out. Check it out. Its very interesting. The site even give you a scale to show the asteroids proximity to earth, its course and what day it will pass by again. Hope that helps.
332248
Look, a 1000 megaton detonation (whether it was due to a nuclear device or due to a meteor impact) would blow the line-of-site atmosphere into space.  We'd all suffer direly if that happened.\n\nA 10,000 megaton (or 10 gigaton) device would locally shatter the crust, and produce a surface wave that would do major damage to the crust all across the world.  Think of a bell: whack it hard enough anywhere and the whole thing rings, and if the whack is hard enough, the temporary standing waves would possibly shatter or crack the bell.  If you don't believe me, look at the Liberty Bell--that crack is (supposedly) due to it being rung hard enough.  Imagine that with the crust of the earth!  Pretty, it ain't.\n\nFrankly, nuclear weaponry is a silly approach to such an effort.  Throw rocks from orbit--you can get nuclear grade energies easily, and you can do it without any radiation.
48622
I'm assuming you mean not counting all objects falling from space (not just asteroids) and all objects being "launched" (molecules from the upper atmosphere, the moon etc).\n\nIn that case the only thing coming to or leaving the earth is light. Since the earth is cooler today than when it formed, some of this original energy has escaped into space in the form of infrared radiation.\nOn the other hand, light from the sun has come to earth and its energy has been stored in the chemicals bonds created during photosynthesis.\nSince the entire volume of the earth has cooled, and living things are only present on the surface, my guess it that the cooling effect wins. Thus the net flux of energy due to electromagnetic radiation has been outward, meaning that the earth has lost weight.\n\nThats just a guess, you could probably ask a geologist and ecologist for some numerical estimates.
504408
Actually, asteroids hit the earth daily.  They are just so small that they burn up in the earth's atmosphere so we don't notice them.  \n\nIf you'd like to keep up to date on the bigger ones, you might want to check here: http://impact.arc.nasa.gov/index.cfm\n(it doesn't speak about anything hitting the earth in a month or so, but you can read more there)\n\n\nAdded:\nHere's another site that shows close approaches of larger objects: http://neo.jpl.nasa.gov/ca/\n\nAs well as different impact risks for known objects:  http://neo.jpl.nasa.gov/risk/
1117857
Ok there are no known meteors that are going to "kill all Earth's life", and I highly doubt you'll be the one to find them while the highly trained astronomers do not. You'll need a very large opening (lens, the big opening at the top) to find meteors that far away. Power (magnification) is not important when the opening is very small. I'm sure you're asking this because of a meteor that is supposedly passing by on the 3rd at the 12th magnitude (you'll need a very good telescope and you can't see it with the naked eye).
776233
Well, considering an asteroid could wipe out life on this planet, and if detected early enough, we might have a chance of preventing that from happening - I'd say yes, it's worth it.
381332
The earth will not explode.  No, whoever said the sun will go supernova failed pre-k.  Ignore them.  Anyway, the earth can not explode, nor can any other planet pretty muc.  The Astroid belt would be to small to be a  destroyed planet, for it would be smaller than pluto if all the rocks were to be put together.  The only way the earth could exploide is with the colision of and object about 4x the size of earth if it was solid...and that, by almost all laws of physics, is impossible.\n\nEdit:\n\nOh, your also asking for the end of the world.  Very well.\n\nThe sun is 4.5 billion years old scientists estimate.  The sun eventually, in 4.5 billion years, swell into a red giant.  It will expand very far, and the earth will be engulped.  Plant life will die, the earth will become dry, and very few organisms will survive.  Eventually, the heat will evaporate the atmoshpere away.  The sun might swallow up the earth, and the earth will be devoured and broken apart from gravity if im correct.  Edit any posts and correct me if im wrpong.  If im not wrong and you correct me, watch how badly I flame your ***\n\nEdit2:\n\nOmfg how many people dont understand!  My god, you idiots!  Comon, a planet getting sucked into a blakc hole?!  YOu retatrds!  Your kidding me right? If your actually voted as the best answer, then the world truly will explode!  You people know nothing in life!\n\nAnyway, at the guy who says the earths core is a neuclear reactor:\n\nThe earth yes might be getting hotter, but that is no reason for it to explode.  Im not saying im with the media, Im only saying that the earths not in any real danger yet.  Im saying that I think It will last some time...but you do have a pont.  I'll do some looking into it.  Gotta show this to my buds on other forums.  Afk.\n\nPs. Good job for playgerizing the whole article but 2 words, by the way!
688079
No, if you think about it-*your* death is all that would matter to you at the time of death- If an asteroid wiped out the Earth, then the consequences for you would be no more than the much much more likely event of you dying in a car accident, or of a fatal stroke. Unless you have some altruistic worry about humankind in general, being killed by an asteroid and being killed by choking on a chicken bone is pretty much the same thing.  Of course, and normal person loves their family and freinds-but again, they are much more likely to die of disease or in a car accident-in addition, there is absolutely nothing you could do about an asteroid, so best to spend any worry energy on common means of death (accident, disease) and preventing that in you and the ones you love, than about low-probability things that you cannot effect.
268872
Certainly.  While life of any sort is unlikely to be found in our solar system (at least beyond the possible existance of bacteria or bacterial fossils) the universe is simply too large for life to not occur somewhere else.\n\nAssuming that life on earth formed and evolved from the basic chemicals of a primordial earth into molecules, and the single celled organisms, it is entirely possible that this could happen somewhere else.  As was previously mentioned, there are a huge amount of stars in the universe, all of which may hold the potential to support a solar system with planets and create conditions likely to that of the Earth 4.5 billion years ago.  Even with a low frequency (1 in billions or more) of any sort of life-form formation, this means what there would likely be life in many places throughout the universe.\n\nI believe that experiments have been performed simulating the primordial chemical environment of the Earth, and subjecting it to electric discharge as would be released by lightning.  It was found that simple compounds such as amino acids could be formed from these reactions, and thus the formation of life may be viewed as a statistical event with a decent probability of occurance, given the correct conditions.\n\nWhile the chance of life existing is significant, the chance of it being intelligent interacting life-forms that we are able to find is much lower.  Even traveling at the fastest speed possible (speed of light), which has never been close to attained for human flight, it would take 15 billion years to reach the outskirts of the universe.  Assuming that life may undergo cycles in which a life-form may evolve, deplete a planet's resources, and then die out, the window of opportunity for finding any life form may be small.  Additionally, since prospective planets to explore that may contain life are likely identified by telescopes, the telescopes show what the planet was like in the past due to the time it takes the light to travel to the Earth.  If we are looking at a planet that is 5 billion light years away, we are looking at the light that was sent from that planet 5 billion years ago.\n\nWhile there are many formidable obstacles, it is not altogether impossible for us to find life on other planets, but I doubt that any of us will see it in our lifetimes.
747685
You have to learn how to do simple arithmetic, and understand simple physics like the conservation of momentum and the conservation of energy.\n\nThen you will see that the effect of the biggest possible nuclear explosion on the Earth's orbit is like the effect of an insect landing on the Empire State Building.  The Earth has been pushed by radiation from solar flares with enormously more energy, hit by asteroids with enormously more momentum, than any puny little man-made nuclear explosion, and its orbit was still not affected measurably.
253010
Hell no, all humans will die from some crisis or big disaster, or maybe the earth will be swallowed by some black hole (Actually it's happening) scientist found out that our galaxy is being sucked by some Massive black hole.\n\nI just don't want to be there when it happens :D
810232
It is estimated that Earth is bombarded by a city-sized asteroid once every 65mil yrs.\ni) Assuming a Poisson distribution, find the probability that Earth will be hit by 2 or less of such asteroids in the next 10000yrs.\nEta Carinae is a suspected hypernova that is 7000 light-years away from Earth. Scientists have observed 200 of such star in many distant galaxies. It was found that the stars have an average life-span of 200mil years with variance 2500mil yrs^2.\nii) Construct a 95% confidence interval for the mean lifespan of Eta Carinae, giving your answer correct to 8 significant figures.\nIt was found later that Eta Carinae was formed 200.01mil yrs ago. \niii) Using the sample of 200 stars earlier, a scientist boldly claimed that Eta Carinae will explode today, causing devastation to Earth in 7000years’ time. By stating clearly the null and alternate hypothesis, test the scientist's claim at 5% level of significance.\nYou may assume the normality of the population of stars observed.
1162500
To answer some of your question......\nThe average velocity of meteoroids entering our atmosphere is 10-70 km/second. The smaller ones that survive the trip to the Earth's surface are quickly slowed by atmospheric friction to speeds of a few hundred kilometers per hour, and so hit the Earth with no more speed than if they had been dropped from a tall building. For meteorites larger than a few hundred tons (which fortunately are quite rare), atmospheric friction has little effect on the velocity and they hit the Earth with the enormous speeds characteristic of their entry into our atmosphere. Thus, for example, it is estimated that the meteorite that produced the Barringer Crater(http://csep10.phys.utk.edu/astr161/lect/meteors/meteor.jpg) was still travelling at 11 km/second when it struck what is now the Arizona desert 49,000 years ago. Such objects do enormous damage, because the kinetic energy carried by the meteorite is the product of the mass and the square of the velocity. A meteorite that large hitting the ocean would create a Tsunami. Whether it would cause as much damage as the one in Indonesia/india/africa, would depend on how close to land the meteorite struck. Change in our ecosystem would not be that great. On the other hand if we were to be struck by an asteroid as in the case of the K-T Extinction, there would be a dramatic effect on the ecosystem. ( just a quick note on asteroids,comets and meteors: Asteroids and comets are both classified as near-Earth objects. Asteroids are made of rock or metal and are thought to have been created in the warmer inner solar system. Comets are composed of ice, rock, and organic (carbon-based) compounds, and are believed to have formed in the cold outer solar sytem. Scientists believe both are "...ancient remnants of the earliest years of the formation of our solar system more than four billion years ago." When asteroids collide, meteroids, smaller rocky bodies, often result. Meteroids are also formed when a comet passes near the sun, and the heat releases dust particles from the comet's icy tail. When a meteroid or asteroid enters the Earth's atmosphere, it ignites, creating a visible streak of light called a meteor. If the object doesn't vaporize completely and crashes into the Earth, it's called a meteorite. \nFinaly, a meteorite, because of its size, would not cause dramatic changes to our eco-system, however, large one can would be able to produce a tsunami.....\n\nChris
799157
Yes, it is true. The name of the asteroid is 99942 Apophis. You can get more in the link. Basically, it will be a near miss in '36 and the Earth's grav, will set it on a course for Earth. If it happens, it will strike the west coast of the US and cause severe regional destruction. This is a very real threat and the teacher (though he may have been off on the dates) he is right. But, dont worry, this is only one mile wide, and will not kill the human race.
487630
ok there are solar flares that reach us but earth's magnetic field sort of protects us.\nso what we need is a combo of some sort\nso how about we go for\nEarth's magnetic pole flipping\nSolar flare(big) or solar increase\nMeteor\nComet\nput them all in the blender and mix\n\nso at the same time the magnetic pole flips\nthe field will drop to zero(not sure on how long)\nat this time a solar flare hits us making the entire sky look like the northern lights(very beautiful at sun set)\nbecause the atmosphere starts to ionize.\nand on the night side a comet heading straight for earth\nbut the comet is over taken by a large meteor that smashes the comet creating a lot of small comets of ice and rock and one mostly untouched meteor about 150-200km or larger in diameter. the meteor can crash in the middle of the pacific right on top of hawaii taking it out and creating a large tsunami that kills most of the people in the costal areas. then the ice covered meteors from the comet will at some time over the next 48 hours end up taking out most of the major urban centers of the world and the farms as well.\nalso the ensuing earthquakes can completely teraform the landscape in to a more mountainous terrain.\nand the electro magnetic serge caused by the solar flare launches all of the armaments across the globe at random GPS co-ordinates.(nuklear, chemical, biological, ETC...)\n\nhows that for a disaster waiting to happen.