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Thursday, August 31, 2006

20/20 out to terrify people...

Last night I decided, against my better judgment, to watch 20/20: Last Days On Earth. Needless to say, I was pretty disappointed by it. It seemed like they only had some of the facts and made the rest of it up as they went along. It seemed to be more science fiction then science fact to me. The only person they had on there that made sense and told it like it is was Steven Hawking. As he said, the Earth is more likely to be destroyed by humankind rather then Gamma Ray Bursts.

This makes me wonder though, are there really people out there who take everything on 20/20 as 100% fact and truth? Is the populous really that gullible?

Remind me to never watch 20/20 again.

They said that a black hole could suck up the earth, umm, anyone have proof that this can and has happened? Scientists have stated that only matter that reached the event horizon in a black hole is doomed to be "sucked in". The biggest misnomer is that black holes are giant cosmic vacuum cleaners, this isn't a whole truth.

Here is what the fact is about Black Holes:


Black holes and quasars ( Source – Answers.com )

When a very massive star collapses, it forms a black hole. A black hole does not have a surface in the usual sense of the word. There is simply a region in space around a black hole beyond which nothing can be seen, because nothing can escape from inside this region. This region is called the event horizon.

Anything that passes beyond the event horizon is doomed to be crushed as it descends ever deeper into the gravitational well of the black hole. Neither visible light, nor x-rays, nor any other form of electromagnetic radiation given off by the particle can escape.

A black hole cannot be seen directly. The only way to find one is by observing the energy released by matter that is falling toward the black hole. As gas and dust particles swirl toward a black hole, they speed up and form a flattened disk. Friction caused by collisions between the particles heats them to extreme temperatures. Just before the particles pass beyond the event horizon, they produce x-rays and gamma rays as their temperatures approach 108 K.

Black holes grow when matter falls into them. A black hole in the center of a galaxy where stars are densely packed may grow to the mass of 109 suns. Energy released from large clouds of gas as they fall into these supermassive black holes can be stupendous. This is the accepted explanation for quasars, sources in which the power output at the center of a galaxy is a thousand times greater than an entire galaxy of 1011 stars. See also Quasar.

One of the most intriguing features of supermassive black holes is that they do not suck up all the matter that falls within their sphere of influence. Some of the matter falls inexorably toward the black hole, and some explodes away from the black hole in high-energy jets that move at near the speed of light. These jets produce radio, optical, x-ray, and gamma radiation. The matter swirling around the black hole must somehow be producing enormous electric and magnetic fields that accelerate electrons to extremely high energies. Exactly how this happens is unknown and is a major focus of research. See also Black hole.

They also talked about Gamma Ray Bursts hitting and destroying the Earths Ozone layer and that the only thing left living will be the microbes. Not a very comforting feeling. The fact about Gamma Ray Busts is such:

Gamma Ray Bursts ( Source: NASA )

Extraordinary explosions.

Imagine an explosion so fierce and intense that it carries with it the power to destroy everything in its path for hundreds if not thousands of light years away. No this isn’t the realms of science fiction but the amazing world of Gamma Ray Bursts.

Astonishing discovery.

Gamma Ray Bursts, or GRBs as they are otherwise known were f irst detected during the late 1960’s. US monitoring equipment on a space satellite set up to detect Soviet nuclear weapons testing began to notice intense gamma ray bursts that were hard to explain.

For a long time it also proved impossible to determine the origin of these bursts. Then in the last decade of the 20th century astronomers made the astonishing discovery that these phenomenal bursts of radiation emanated from the observable extremities of the known Universe.

Nothing rare.

Dramatic though the discovery of Gamma Ray bursts was, there is nothing particularly rare about them since they were, and continue to be spotted at a rate of around one a day. But what were these bursts? They were obviously some form of intense radiation coming from an unimaginably distant location but how could they be explained?

Very quickly astronomers began to surmise that GRBs were exploding stars. These are usually known as supernovas but GRBs were in a whole new category and made even the tremendous force of a supernova look minuscule by comparison. Scientists have now speculated that Gamma Ray Bursts may be associated with black holes capable of releasing a fireball of energy into a high pressure jet that in turn creates the shock waves that lead to the formation of Gamma Rays.

Long and short duration.

For all their astonishing power GRBs are of extremely short duration and fall into two categories. The first involves those with an average of just a third of a second and others with a much longer average span of 30 seconds. Astronomers then conjectured that different causal forces lay behind the origin of the two categories. As it is there is still a huge amount we do not understand about GRB’s, but one thing we do know for sure is the great damage they would be capable of causing.

Deadly consequences.

Since most GRBs are at the extremities of the Universe and occurred when the Earth was very young there is seemingly nothing to worry about. Yet the very nature of GRBs mean that an explosion at even several thousand light years distance could prove deadly to all life on Earth. Indeed some scientists believe that GRBs were responsible for at least some of the frequent mass extinction's that have swept the planet over millions of years. For more on the possibly drastic implications that GRB’s could hold for our planet please turn to the accompanying link:

http://www.nature.com/nsu/030922/030922-7.html

Our Sun - the ultimate end!

For the ultimate disaster representing the End of the World we should look no further than our own Sun. Eventually - in many millions of years - this too will erupt in a vast fireball and completely vaporize our planet. This may be a long time in the future but the Sun has shown recent signs of an increase in activity.

They also mentioned the exploding of Yellow Stone National Park’s Caldera. That’s not a matter of if, that’s a matter of when. It has happened in the past and it will happen again according to Discovery Channel and the scientists involved in the information.

Here’s what they had to say:

Yellow Stone Caldera ( Source: Discover Channel )

The VEI scale runs from zero to eight. The higher the VEI number, the bigger — and less frequent — the eruptions. On one end there are the burbling, rather gentle eruptions that happen on the big island of Hawaii. These happen daily on Earth, and even with their occasional impressive fountains of lava, they rate a zero on the VEI.

At the other extreme is the Yellowstone eruption of 2.1 million years ago, which is described on the VEI as an eight: mega-colossal, with a towering ash cloud 10 miles high that pours out at least a thousand cubic miles of ash. That Yellowstone eruption had 10 times the ejected material as a VEI 7 volcano, which modern humans have never seen either.

In fact, the last VEI 7 eruption was in Toba, Indonesia, 74,000 years ago, and it caused such global cooling that some scientists think it nearly drove humans to extinction.

The largest known eruption in the last several thousand years is believed to be that of Tambora, Indonesia, in 1815. It was tens of times more massive an eruption than Mount St. Helens in 1980. Despite pouring out 7 cubic miles of ash and causing short-term global cooling, Tambora was small fry compared with any of Yellowstone's big eruptions, or even the eruption of Toba 74,000 years ago.

No eruptions of this magnitude have happened since the dawn of civilization, about 10,000 years ago — which is lucky for us, and perhaps one reason civilization has been able to develop.

As with Yellowstone, none of the other caldera-based supervolcanoes around the globe fit the classic volcano image.

Calderas are broad, sunken areas often filled with lakes, ringed with hot springs and landscaped with domes of lava. They are something like cauldrons, after which they were named, and tend to be the largest volcanoes on the planet — hence the less formal name they are sometimes given: supervolcanoes.

Like other calderas worldwide, the Yellowstone caldera landscape was created by the "roof collapse" on a subterranean chamber after molten rock — called magma — was ejected in massive prehistoric eruptions. It's almost as if there was a giant magma balloon under the surface that suddenly deflated. The deflation itself is the super-eruption, and the sunken land left behind is the caldera.

Also, as with many other calderas, there is still hot material not far underground at Yellowstone, which is why there are so many hot springs and geysers today.

As for what caused the land to inflate with magma and explode in the first place, it was a powerful "hot spot" welling up from deep in the Earth and melting rock closer to the surface into magma, says Smith.

But what caused the hot spot? And what can explain it today? Scientists are still learning answers to these questions.

"A hot spot is a long-lived point spot of magmatism," explains geologist Paul Ihinger of the University of Wisconsin at Eau Claire. Among the most famous places made by hot spots are the Hawaiian Islands, Iceland and, of course, Yellowstone.

In the case of Yellowstone, the hot spot has left a 350-mile trail marked by several generations of ever-older and deader calderas marching away to the southwest of Yellowstone.

The oldest is a 15- to 16.5-million-year-old dead caldera straddling the Oregon-Nevada state line near McDermitt, Nev. The trail of dead calderas is evidence that the hot spot has remained in place while the North American continent has moved southwest over it.

The next thing they talked about was an asteroid hitting Earth. Again, that’s not a matter of if but a matter of when. The Earth has been hit by asteroids, meteors and other space debris in the past, and is hit by smaller meteorites to this very day. According to NASA we’ve had many near misses in the past. But, seriously, this probably won’t happen in our lifetimes, or even our children’s lifetimes. Or so scientists hope. NASA has been working on finding ways to “deflect” an asteroid if it should target our planet. They have some pretty far fetched ideas, but they could very well work, or not. For this one we have nothing else to do but wait and see what happens.

They also talked about Nuclear War, okay, so that is a possibility, considering the state of things. This one is not far fetched and is a possibility. What more can I say about it? Of course I’m hoping it doesn’t happen.

Next was Germs/Disease: Plague and Bioterrorism, again not so far fetched. Bioterrorism is a very real threat.

Then there was the all-time favorite Global Warming/Climate Change, again, not far fetched. The human race is killing our planet with all the gasses and toxins we’re spewing into the atmosphere. It’s called progress, I call it killing our planet. But there’s not much that one person can do about something this big. An example of the climate changes is the recent heat wave that hit North America. Temperatures reached 100 degrees Fahrenheit and higher. What can be done to fix this? The scientists seem to think they have an answer to this question. Stop pumping so much CO2 into our atmosphere, but that’s the cost of using our fossil fuels and driving our cars, trucks, busses and so on.

Okay, time for me to hop off my soap box.

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