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(1)Amateur Astronomy -- A Hobby as Big as the Universe
(2)End of the universe?
(3)End of Science
How would you like to take a trip to some of the most exotic and beautiful places in deep space without leaving the safety of Earth? Just imagine, exploring the surface of the moon, watching the weather on Jupiter, peeking into a stellar nursery, or gazing into the heart of a giant spiral galaxy. Amateur Astronomy delivers just that and much more! Amateur Astronomers are hobbyists interested in observing the heavens for personal enjoyment or public education You don't need to be a scientist or an optical expert to participate, and you don't even need to own a telescope. Many amateurs are just ordinary people who look at the skies through, telescopes, binoculars or with the unaided eye and a star chart. Amateur Astronomers come in ages ranging from grade schoolers to senior citizens and in both sexes. Some observe just for the fun of it, while others build their own telescopes, perform astro-photography, or even scientific research, but all share a common appreciation of the wonders of the universe.
Scientists working at the Sudbury Neutrino Observatory (SNO) in Ontario, Canada have finally revealed the fate of the Universe ... The have managed to calculate the mass of that elusive particle, the neutrino, and come to the conclusion that while there is a colossal amount of neutrinos in the universe their combined mass is not enough to halt the outward expansion of the universe. The universe is therefore destined to expand forever until it becomes a cold, dark place devoid of all signs of life. What is a neutrino anyway? Technically: a lepton with zero charge, spin 1/2 and an extremely small mass. They only interact with other particles through weak interaction and their existence was originally postulated by Wolfgang Pauli to account for the missing energy in beta decay. It is thought that they account for a large portion of the *dark matter* in our universe. There are three types: electron neutrinos, tau neutrinos and muon neutrinos. The physicists working on the project were trying to explain the problem of the missing solar neutrinos. The problem is as follows: the nuclear reactions that fuel the Sun emit a vast quantity of electron neutrinos, but experiments find that only a fraction of the expected amount of electron neutrinos are reaching Earth. The experiments at Sudbury proved that neutrinos can oscillate between the different types accounting for the discrepancy in the amount of electron neutrinos. An interesting discovery you might think, but it also has far reaching implications in that the direct evidence for solar neutrino transformation also indicates that neutrinos have mass and by combining this with previous information, it is possible to set an upper limit on the sum of the known netrino masses. According to Scott Tremaine, professor of astrophysical sciences at Princeton University: "This is the final clue we need to determine the fate of the Universe". Missing Mass In order for the expansion of the Universe to be halted and for it to eventually contract into a "Big Crunch" the mass of the Universe must be above a certain value. The stars and galaxies in the universe which are detectable by our telescopes and instruments only account for a small fraction of the mass of the universe. This is clear from indirect evidence, like the rotation of galaxies for example (see article on dark matter
One last thought on scientific progress: could scientists someday work themselves out of a job? Science seems to progress at such a great pace. And that pace seems to be steadily accelerating. Isn't it possible that someday we'll know everything we could possibly want or need to know? A hundred years ago, it was quite fashionable to predict the demise of science. "Everything that can be invented has been invented," pronounced Charles Duell, head of the U.S. Patent Office in 1899. It was thought that science would soon be a mopping up exercise. The values of certain physical constants would be refined to a few more decimal places. Bigger telescopes would put more stars on the map. Stronger microscopes would find smaller microorganisms. But basically, we shouldn't expect any more surprises. Well, you can see what happened to people who made such predictions. They missed the revolution that was about to happen. And even so, says Dr. Bruce Hunt, history professor at the University of Texas at Austin, scientists such as Stephen Weinberg and Steven Hawking have been caught making very similar predictions today. Dr. Hunt says, "That's a parallel. They have a very different expectation of what the final theory will look like. But that kind of theory was flourishing at the end of the 19th Century and now, the 20th Century." Science can never come to an end, says Dr. Harold Kozac, Adjunct Professor of Astronomy at Wagner College, Staten Island, New York. "We're always battling disease. We're always looking to further space exploration. Our sun -- in about 4.5 billion years -- is going to die. It's going to become a red giant and then a white dwarf. Our descendants will have to leave the planet because the solar system is doomed. As long as humanity continues, there will be problems and science is the only way to solve it," he says. |