Hum Posted September 9, 2011 Share Posted September 9, 2011 Scientists have shown that the Earth's surface became enriched with precious metals by impacting meteorites. The Earth's crust and mantle has considerably more gold than expected from favoured models of planetary formation. A study from the University of Bristol looked at some of the oldest rocks on Earth, demonstrating that gold was delivered by meteorites long after their formation. Their results are published in Nature. While the Earth was forming, iron sank to the centre of the planet, forming the core. Any precious metals in the planetary mix would have gone with this iron and concentrated in the core, leaving the mantle devoid of elements such as gold, platinum, and osmium. But this is not what we observe. In fact, the silicate mantle has up to 1,000 times more gold than anticipated. Several reasons for this enrichment were proposed in the past, including delivery by meteorites, although until now it has not been possible to prove. By measuring isotopes in rocks that are nearly four billion years old from Greenland, the team has managed to date the gold delivery, and to relate it to an event known as the "terminal bombardment". more Link to comment Share on other sites More sharing options...
MrFunEGUY Posted September 9, 2011 Share Posted September 9, 2011 Stuff like this always interests me. Cool Post. Link to comment Share on other sites More sharing options...
Yusuf M. Veteran Posted September 9, 2011 Veteran Share Posted September 9, 2011 That's pretty interesting. I guess it makes some alien invasion movies more plausible. Link to comment Share on other sites More sharing options...
mudslag Posted September 9, 2011 Share Posted September 9, 2011 That's pretty interesting. I guess it makes some alien invasion movies more plausible. Why? The least resistance would be to gather up the billions and billions of meteors in a solar system then to attack a planet with life thats even remotely capable of defending itself. Rocks dont fight back. If our history is to be any kind of guide, it should be remembered that even a lesser advanced group can still defend against a more advanced one. While war of the worlds is a cheesy entertaining movie/book, it still hold some true aspects that germs and bacteria can be a life forms greatest foe. Specially to a life form who has never encountered it before. That is even a big concern for humans who plan on traveling to other worlds today. There was even concern back in the 60s when we went to the moon that we didnt bring back "something" that could harm us. Link to comment Share on other sites More sharing options...
Yusuf M. Veteran Posted September 9, 2011 Veteran Share Posted September 9, 2011 Why? The least resistance would be to gather up the billions and billions of meteors in a solar system then to attack a planet with life thats even remotely capable of defending itself. Rocks dont fight back. If our history is to be any kind of guide, it should be remembered that even a lesser advanced group can still defend against a more advanced one. While war of the worlds is a cheesy entertaining movie/book, it still hold some true aspects that germs and bacteria can be a life forms greatest foe. Specially to a life form who has never encountered it before. That is even a big concern for humans who plan on traveling to other worlds today. There was even concern back in the 60s when we went to the moon that we didnt bring back "something" that could harm us. I was referring to the alien invasion movies that involve aliens coming to Earth for its resources. My best friend seems to think it's silly because he believes that whatever resources are on Earth can be found in great abundance elsewhere. I always told him it's easier to go to a planet that has what you're looking for than to go from moon to moon and find very little of what you're looking for. The fact that Earth has more resources in its upper mantle and crust than it should gives those movies a little more plausibility. As for defending ourselves, I'd say that's possible if the aliens play by our rules. We wouldn't stand a chance if they were to bombard us from orbit with weapons of mass destruction (or even biological weapons). Link to comment Share on other sites More sharing options...
Hum Posted September 9, 2011 Author Share Posted September 9, 2011 I saw a TV show last night suggesting aliens wanted gold from Earth. But I just can't see any reason to take gold. It is not a fuel, energy source. And an advanced civilization able to travel between stars, should be able to synthesize any element. Link to comment Share on other sites More sharing options...
Solid Knight Posted September 9, 2011 Share Posted September 9, 2011 Meteroites bring elements from the perioditc table of elements to Earth. Link to comment Share on other sites More sharing options...
FMH Posted September 9, 2011 Share Posted September 9, 2011 Apparently South Africa was their favourite country! Link to comment Share on other sites More sharing options...
mokthraka Posted September 9, 2011 Share Posted September 9, 2011 I was referring to the alien invasion movies that involve aliens coming to Earth for its resources. My best friend seems to think it's silly because he believes that whatever resources are on Earth can be found in great abundance elsewhere. I always told him it's easier to go to a planet that has what you're looking for than to go from moon to moon and find very little of what you're looking for. The fact that Earth has more resources in its upper mantle and crust than it should gives those movies a little more plausibility. As for defending ourselves, I'd say that's possible if the aliens play by our rules. We wouldn't stand a chance if they were to bombard us from orbit with weapons of mass destruction (or even biological weapons). if they bombard us with weapons of mass destruction, it could damage whatever resource they need. not to mention in most movies they come for something like water, which is entirely pointless, since they could just go to Europa or something for water. Link to comment Share on other sites More sharing options...
Yusuf M. Veteran Posted September 9, 2011 Veteran Share Posted September 9, 2011 if they bombard us with weapons of mass destruction, it could damage whatever resource they need. not to mention in most movies they come for something like water, which is entirely pointless, since they could just go to Europa or something for water. You're right. They'd likely use smart weapons (e.g. drones that seek out human life). That way, everything else would stay intact. Link to comment Share on other sites More sharing options...
mokthraka Posted September 9, 2011 Share Posted September 9, 2011 You're right. They'd likely use smart weapons (e.g. drones that seek out human life). That way, everything else would stay intact. No. Because they would still sustain casualties. It would be pointless to attack earth for resources. What happens when there are just a few people left and they say "**** it." And just launch nukes at random. Link to comment Share on other sites More sharing options...
Yusuf M. Veteran Posted September 9, 2011 Veteran Share Posted September 9, 2011 No. Because they would still sustain casualties. It would be pointless to attack earth for resources. What happens when there are just a few people left and they say "**** it." And just launch nukes at random. Since they're advanced enough for interstellar space travel, it shouldn't be surprising if they have a means of disabling our weapons (including thermonuclear devices). Think about it: the smartest way to fight a war would be to fight one without the risk of casualties. If they use pure technology (drones with energy-based weapons and defensive force fields, for example), then they'd hardly sustain a single casualty. They might even be able to do that while mining our resources from orbit. Compared to other planets in our solar system, Earth is rare because of its natural resources (minerals, precious metals, etc). Then again, I guess it does seem like more trouble than it's worth. Link to comment Share on other sites More sharing options...
DocM Posted September 10, 2011 Share Posted September 10, 2011 If I were an alien commander I'd kidnap a representative sample of each human ethnicity and develop targeted bioweapons that would spread through normal interactions. Sit back and wait for critical mass. Link to comment Share on other sites More sharing options...
Rigby Posted September 10, 2011 Share Posted September 10, 2011 Meteorites brought everything to Earth, they're what the planet is made of. Link to comment Share on other sites More sharing options...
Solid Knight Posted September 10, 2011 Share Posted September 10, 2011 Assuming it is even economically feasible to conduct an interstellar invasion in the first place or that they have an interstellar military force capable of invading an entire planet and said military force actually has experience in planet scale invasions. Link to comment Share on other sites More sharing options...
Hell-In-A-Handbasket Posted September 10, 2011 Share Posted September 10, 2011 I saw a TV show last night suggesting aliens wanted gold from Earth. But I just can't see any reason to take gold. It is not a fuel, energy source. And an advanced civilization able to travel between stars, should be able to synthesize any element. True, but it is one of the few elements with its conductive properties and soft enough to easially make into any shape with verry little effort Link to comment Share on other sites More sharing options...
mudslag Posted September 10, 2011 Share Posted September 10, 2011 True, but it is one of the few elements with its conductive properties and soft enough to easially make into any shape with verry little effort That we know of, just this year we added 2 new elements to the periodic table. My guess is that it's a table that will continue to grow with time. Link to comment Share on other sites More sharing options...
DocM Posted September 11, 2011 Share Posted September 11, 2011 Some new research from the Max Planck Institute is indicating that gold and many other heavy elements were not made inside supernova explosions as previously believed. The new work indicates that they were made when supernova remnants called neutron stars collided. This isn't as rare an event as one might expect since a large number of stars are red giants in binary systems, 2 stars orbiting each other, and after both go supernova they eventually spiral towards each other and collide. Link to comment Share on other sites More sharing options...
Recommended Posts