anyone notice that its not just the earth thats warming up.....everything from mars to pluto is warmer then they should be. I heard that some scientists shot some lasers or something at pluto (probably wrong on how they did it) but they discovered even though pluto is farther from the sun then ever. It was 10 degrees warmer then its supposed to be. As well out of no wheres One of the eyes on Jupiter (which has been around for hundreds of years) just up and disappeared. The same has happened to a number of lines on Jupiter. As well Mars is substantlally warmer then it should be as well. So Not ALL of the Global Warming is due to humans, albiet we arent helping, we arent the sole source. if i remember correctly (definitely have to find the article on this that i read) its Star dust thats seeping into the solar system because somehow the protective "forcefield" created by the sun has some holes in it for some reason. Honestly I have no clue how the Sun keeps shit like stardust (whatever that is) out so honestly im at a loss for words as to really figure out how it will effect us. The article did mention that the supposed peak of this stardust would fall in 2012...............

Yep, from what I've heard, it's the whole solar system that's warming up. 2 possible explanations :

- Solar cycle at its peak...but not likely

- Red dwarf passing by (Nibiru anyone ?)...but then again, not likely.

Oh well, we'll know soon enough anyway I guess.

No, I haven't really noticed... but its been awhile since i visited the martian surface...

Errr... no. A red dwarf is a star. you don't need an infrared telescope to see it, because it emits its own light. Furthermore, red dwarfs are relatively cool stars, definitely cooler than our own sun. Thus, for the thermal effects to be noticeable, the new star would have to be very close to our system - so close in fact that you would clearly be able to see it in daylight with the naked eye.

A brown dwarf, a gas giant so big its on the verge of nuclear fusion, but not quite, is a relatively large astral body which does not emit visible light, only infrared. It is still much smaller than our Sun.

Also, it is geometrically impossible that an astral object can be seen only from the South Pole. Earth is a sphere, if you can see something from the South Pole, you can see it from the entire Southern Hemisphere.

To continue, the Earth's magnetic field cannot be modified or "dropped" by the proximity of a large astral body. The magnetic field is caused by the dynamo effect - circulating electric currents within the molten iron core of the planet. To disrupt this effect, Earth's rotation would need to be slowed down or stopped.

If something actually managed to expend that much energy on the planet, we would all be very much dead long before the magnetic field dissipated.

Simple proximity of a large astral body, however, is not enough to do something like that. A star passing through the Solar system would, however, seriously knock all planets about, hence my joke about being rammed by Jupiter. But as I said,  there is no such star in the vicinity of the Solar system. The whole Nibiru, Planet X thing is a hoax, nothing more.

I believe there were so far three Extinction Events in Earth's past. I think one of them pretty much wiped out 95% of all life on the planet. And yet, as you say, life bounced back. I would however, attribute that more to the incredible resilience of life itself, than to being favoured by something or someone.

As for the asteroid impact, there are many shows on Discovery, and some tend to be a little... flamoyant. As far as I know, the Extinction Event caused by the asteroid impact was not something which happened overnight. It was a rather long process in fact... paleonthologists can confirm that as they know that not all dinosaurs died off at the same time. In different part of the world the extinction happened at different rate.

What probably happened (because no one knows for sure and its all speculation) is that the impact threw up so much fine dust into the atmosphere that it crated an aerosol layer which blocked out a large percentage of Sun's radiation from reaching the surface - something simmilar is predicted to happen if there ever is a widespread nuclear war, and a simmilar effect caused a "mini ice age" when Krakatau exploded (the famous year-long winter which was felt around the world).

However, this effect does not last just one year - it lasts long enough to trigger an Ice Age! What happens is that Earth falls into a sort of a feedback loop. Lowered temperatures caused by the dust cloud cover cause the buildup of polar icecaps beyond a critical level needed to alter the planet's albedo - the amount of energy reflected back into space increases because the ice and snow cover are white and absorb far less energy than darker oceans and landmasses. This in turn lowers the temperatures even further until a new equillibrium is found.

Dinosaurs,  dependant on abundant plantlife which can no longer survive the altered climate, start to die of. First to suffer are of course plants. Herbivore populations start to drop because those giant reptiles need a massive amount of food daily to keep going. Naturally, carnivores soon follow.

Who survives? The underdogs of the food chain - mammals and small critters (compared to dinosaurs) who can survive on much less than the giants now dying across the world. Mammals are also far better equipped to deal with a cold climate. Size ceases to be an advantage and becomes a death sentence.

Fish and marine life of course survive as well, largely protected because even during an Ice Age there are plenty of oceans to swim in.

As for oxygen, keep in mind most of our oxygen actually comes from the oceans, from the phytoplankton. It needs sunlight much as other plantlife does for photosynthesis, but since I dount the world was scolded in blistering air during the impact, I think much of the plantlife survived in the tropical regions, where the most oxygen producing forests still are (for the time being).

In the end, I don't think we humans can permanently damage this planet or render it uninhabitable yet. We can kill ourselves off, yes, but life itself is just too tough. If it can exist in an oxygen-free environment at temperatures of several hundred degrees Celsius and produce complex life forms such as worms and crabs, then it can survive anything we can throw at it as is.