POSTED by: on 10/14/2009
(0)Between 200BC and 600AD a group of people created a series of huge line drawings in the ground. The drawings are so big that they can only be fully seen from the air. Even today, more than 1500 years after their creation, no one has yet discovered what their purpose is.
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POSTED by: on 10/13/2009
(0)In late 2006, a Nasa probe, called Deep Impact, collided with the Tempel 1 comet. The resulting outgassing lasted for 13 days and released between 33 and 66 million pounds of matter.
The Deep Impact mission was instituted to learn more about the chemical makeup of comets. The spacecraft was made up of two parts, the flyby section and the impactor. The impactor hit the comet with the same force as an explosion of five tons of dynamite. The flyby section then flew through the plume of debris and collected data about it. The data was later radioed back to earth for analysis. The impactor also had a camera and recorded images until about 3 seconds before impact.
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POSTED by: on 10/11/2009
(1)Nitroglycerin is extremely dangerous to work with, it explodes from even small physical shocks, and over time it becomes even more unstable.
In 1867, Alfred Nobel combined Nitroglycerin with diatomaceous earth to create a mixture known as dynamite. In addition to being used for mining and construction purposes, dynamite became a widely used tool of death and destruction.
In 1888, a french newspaper incorrectly printed a obituary about Nobel, who hadn’t yet died. The article harshly condemned him for creating a more efficient method of killing. This article had such an effect on Nobel that when he died he established the Nobel Prize to honor those who have made significant contributions to science.
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POSTED by: on 10/09/2009
(0)…On the Moon. At the end of the Apollo 15 mission, immediately prior to returning to their spacecraft, astronauts David Scott and James Irwin performed a short experiment to prove that Galileo Galilei was correct in his theory that objects in a vacuum fall at the same rate regardless of their mass.
The experiment involved dropping a geology hammer and a falcon feather at the same time and seeing which one hit the surface first. On earth the hammer will always hit the ground first, but on the moon, where the atmosphere is all but nonexistent, both hit the ground at the same time. The actual cause for the disparity on earth is air resistance, not a difference in mass. Linked is a video of the experiment taken from the surface of the moon.
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POSTED by: on 10/08/2009
(0)Early on the morning of June 30th, 1908, a huge explosion rocked the Siberian forest. The explosion was so strong that it felled trees in a 850 square mile area around the blast site.
100 years later the cause of the explosion is still a mystery. The prevailing theory states that a meteorite or comet about 120 feet across entered the atmosphere above the Siberian forest and exploded at an altitude of 6-10 km above the ground. It released about 185 times the energy released by the detonation of the bomb over Hiroshima. The resulting shock wave stripped the branches and bark off the trees immediately below the air burst, felled the trees for tens of kilometers around and blasted a large amount of debris into the atmosphere.
There wasn’t a scientific expedition to the site of the explosion until 19 years after it happened.
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POSTED by: on 10/07/2009
(0)In the year 79 C.E. Mount Vesuvius, an active volcano near Naples, Italy, erupted with fatal force. OVer the course of two days it completely buried two Roman Cities, Herculaneum and the more famous Pompeii.
Pompeii and Herculaneum were two wealthy cities in the Roman world, both situated at the base of the fertile slopes of Mount Vesuvius. This placed them right in the path of several pyroclastic flows and surges that contributed, in addition to ash-fall, to the complete burial of both cities under tens of feet of volcanic materials.
People were caught in the middle of their daily lives and their homes have been kept in a remarkable state of preservation by the dense ash covering them. The bones of the victims have been found in small cavities in the ash. When these cavities are filled with plaster and the excavated, archaeologists are left with sulptures of the residents of the cities, caught in their final moments of life, some with such clarity that even the expression on their faces may be seen.
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POSTED by: on 10/06/2009
(0)In late 1977, two small spacecraft launched from earth and began a mission to visit Jupiter and Saturn and learn more about them. 32 years later, these two spacecraft, called Voyager 1 and Voyager 2 are flying at incredible speeds out of the solar system and into the vast regions of interstellar space; all the while, sending back new data about what they find so far away from our planet. Both spacecraft have now crossed the termination shock and are flying traveling through the Heliosheath, the final layer of the solar system before leaving the Heliosphere and reaching interstellar space.
The spacecraft are powered by radioisotope generators that are expected to provide power until about 2025. However, as the generators lose capacity, various experiments will need to be shutdown in order to conserve power.
It is unknown when the Voyager spacecraft will reach the Heliopause.
Both Voyager 1 and Voyager 2 also carry a small gold plated copper phonographic record (The Voyager Golden Record), containing greetings in various languages, music and pictures. These records are there in case one of the spacecraft is found by extraterrestrial beings, though the chance of this happening is next to nothing.
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POSTED by: on 10/05/2009
(0)Thomas Edison may have invented the first commercially practical light bulb and popularized the usage of electricity, but Nikola Tesla made our modern electrical infrastructure possible.
In the late 1800′s Thomas Edison founded the Edison Illumination Company, which provided electricity to a small number of customers in Manhattan. The electricity was transmitted as 110 volts of DC current and thus could only be transmitted about two miles. Tesla introduced a new system, called alternating current, which allowed the power to be transmitted over longer distances by stepping up the voltage of the electricity with transformers. Without this new system, it would not have been economical to run national power grids because there would have to be a generating station every few miles.
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POSTED by: on 10/04/2009
(1)Household oil fires are notoriously hard to put out, they are pools of fuel that are burning and pouring water on them is not a good idea. Now imagine a pipe from which thousands of gallons of highly flammable oil and gas are shooting out and immediately burning. These fires are typcally so hot that it is impossible to approach them without first cooling the ground around them and working under a continual spray of water. On top of this, every minute that the fire burns means more toxic smoke in the air, more toxic sludge on the ground, and more danger in putting it out. These factors all combine to give those men and women who fight oil well fires the name “HellFighters.”
So how do these HellFighters actually put out burning oil wells? The only way is to starve them of oxygen using methods ranging from blowing them out with concentrated streams of water, to dowsing them with flame retardant chemicals, to the most spectacular of methods, blowing them out with dynamite.
The original method for putting out burning oil wells is blasting them with dynamite. The basic idea behind this technique is simple, detonate an explosive in the heart of the fire and the resultant explosion will remove all the oxygen in the area and thus starve the fire. In practice, it is much harder. First the area must be cooled and all debris removed to prevent re-ignition. Then the firefighters must remove the crust of burned oil that has built up around the wellhead. It may sound easy, but they are working right next to a 3000 degree fire and must continually work behind heat shields and be cooled by streams of sprayed water. Once the area is clear, they have to maneuver highly volatile explosives into the heart of the fire without detonating them prematurely. Then they detonate them and put out the fire. Finished right? Nope, the firefighters then have to go in, remove the old wellhead, replace it with a new one, and then shut off the flow; all this with the oil still raining down on them and threatening a deadly explosion if even the least of sparks is made.
Needless to say, oil well fires are extremely dangerous and difficult to put out.
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POSTED by: on 10/03/2009
(0)
Infrared light is a type of electromagnetic radiation that has a longer wavelength than visible light. Despite the fact that it’s invisible, it is actually all around us all the time. The interesting thing, is that a digital camera with a CCD in it (most digital cameras use them) can see infrared. In fact they are so good at seeing it, that digital cameras actually incorporate an infrared filter to prevent interference.
Tv remote controls use infrared light to send signals to the tv. While they are invisible to the naked eye, a digital camera (even one with the IR filter still in place) can see them. See the video demonstration here.
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