.... is 22 degrees. Since the sun is 1/2 of a degree across, the radius of the halo is 44 sun-widths. Occasionally you may see a second halo at 46 degrees from the sun (that is, with a radius of 92 sun-widths). This is produced by sunlight passing through both the side and bottom of each crystal. Moonlight will also produce a halo, around the moon, with the proper layer of cirrostatus. Another common optical effect is known as "mock suns" or "sun dogs" or "parhelia" (Greek for "with the sun"). These bright spots on either side of the sun, outside of the halo, occur when sunlight passes through the sides of capped columns, bullet .....

.... of which hide and replicate. The first of these is the Trojan Horse programs, the name of which comes from the Greek legend that told how Greek soldiers gained entry to the city of Troy in a giant, hollow wooden horse and thus captured the city, ending the Trojan War. Though not technically a virus it is still dangerous and could cause permanent damage to your operating system. A Trojan Horse program is a program disguised as a game, a utility or an application. When run, a Trojan Horse will do something devious to your computer while appearing to do something useful, such as deleting every file beginning with the letter 'H' .....

.... Alligators are important ecologically and are dependent on the spatial and temporal patterns of water fluctuations. Patterns of courtship, mating, nesting, and habitat use are all dependent on marsh water levels. Alligators are a great study organism to study the adaptations and responses to the seasonal changes to the hydrological conditions in the everglades. Alligators seem to be able to adjust the height of the nest egg cavity based on the spring water levels, which historically indicated the water levels later in the nesting season. Water levels also determine the availability of food therefore affecting the patterns of gr .....

.... a lot for plating. Plating such things as electical contacts. Tin is also used as a protective coating. This protective coating can be as small as 15/1,000,000 of an inch. This protective coating protects against rust on steel and other metals. A coating of tin also gives a great look to plain old steel. Tin cans for food prevents weak acids from damaging the inside of the can. Not many cans are made of tin since aluminum started to be used for cans tins use dropped sharply. Tin is also used to coat staples, pins, bronze bell, pewter pitchers and many others things. Another popular tin mixture is tin and lead. Tin .....

.... processes was proposed by Charles Darwin. His most famous book, On the Origin of Species by Means of Natural Selection (1859), is a landmark in human understanding of nature. Pointing to variability within species, Darwin observed that while offspring inherit a resemblance to their parents, they are not identical to them. He further noted that some of the differences between offspring and parents were not due soley to the environment but were themselves often inheritable. Animal breeders were often able to change the characteristics of domestic animals by selecting for reproduction those individuals with the most desirable qual .....

.... empirical research that does exist, more often than not, does not define the kind of touch or massage methodology employed, and massage is often rolled in with a range of other therapeutic methods (Westland 1993). Nevertheless, interest in massage as a valid means of therapy is on the increase and in particular in the West, where stress is one of the most commonly experienced states, massage has a clear role to play in reducing stress and helping people learn to recognise early stressful symptoms as compared with a more relaxed and less stressed state. With pharmacology, medical technology and the ever-increasing depersonalisatio .....

.... This instrument, called a hydrostatic balance, was used by weighing the objects in water. Galileo returned to Pisa in 1589 and became a professor in math. He taught courses in astronomy at the University of Pisa, based on Ptolemy's theory that the sun and all of the planets move around the earth. Teaching these courses, he became more understanding of astronomy. In 1592, the University of Padua gave him a professorship in math. He stayed at that school for eighteen years. He learned and believed Nicolaus Copernicus's theory that all of the planets move around the sun, made a mechanical tool called a sector, explained .....

.... are complete, the volume of oil spilled in U.S. waters declined by two-thirds compared to the year before, representing the lowest amount recorded since the Coast Guard began publishing data in 1973. And more than three-fourths of those spills were under 10 gallons -- less than a car's fuel tank holds. Even as the industry strives to reduce the number and size of oil spills still further, we've also learned a lot over the past decade about the best way to respond when, despite all of our precautions, a spill does occur. Since the passage of the Oil Pollution Act of 1990, the petroleum industry has invested nearly $17 billio .....

.... and trained the crew to make the workshop habitable. At the same time, engineers "rolled" Skylab to lower the temperature of the workshop. Skylab's 2nd manned mission - May 25th to June 22nd Astronauts; Charles Conrad, Jr. Paul J. Weitz Joseph P. Kerwin The crew meats with Skylab on the fifth orbit. After making many repairs, including deployment of parasol sunshade which cooled the inside temperatures to 75 degrees F, by June 4 the workshop was in full operation. In orbit the crew conducted solar Earth resources experiments, medical studies, and five student experiments; 404 orbits and 392 experiment .....

.... external bleeding, you bleed from every opening on your body, blood fails to clot, so if you get cut in any way your body will never stop bleeding from that wound. Ebola could spread and infect everyone in the world in 48 hours. Marburg, Germany In this small German town people were taking tests on African monkeys. These monkeys were infected with the infamous Ebola virus. What's horrifying about Ebola is that the virus can change easily, as it did with this newest strand, Marburg. Now, the original Ebola is known as Ebola-Zaire. Marburg is not as bad of a virus as Ebola-Zaire is, the fatality rate is 1 out of 4 people, while Ebo .....