The Stars And Galaxies Essays - Spectroscopists, Stellar Astronomy

The Stars And Galaxies Essays - Spectroscopists, Stellar Astronomy The Stars And Galaxies MEGAN JACKSON MS. KEYS SCIENCE DECEMBER 5,2000 THE STARS AND GALAXIES Have you ever looked up at the sky and wondered what are those bright and shiny things up there. Stars: a natural luminious body visible in the sky especially at night. A self-luminious gaseous celestial body ofgreat mass which produces energy by means of nuclear fusion reactions, whose shape is usually spheroidal, and whose size may be as small as the earth or larger than the earths orbit. Galaxies: Any of the very large groups of stars and associated matter that are found throughout the universe. In 1802, William Wollaston noted that the spectrum of sunlight did not appear to be a continious band of colors, but rather had a series of dark lines superimposed on it. Wollaston attributed the lines to natural boundaries between colors. Joseph Fraunhofer made a more careful set of observations of the solar spectrum in 1814 and found some 600 dark lines, and he specifically measured the wavelenght of 324 of them. Many of the Fraunhofer lines in the solar spectrum retain the notations he created to designate them. In 1864, Sir William Huggins matched some of these dark lines in the spectra from other stars with terrestrial substances, demonstrating that the stars are made of the same materials of everyday material rather than exotic substances. This paved the way for modern spectroscopy. Since even before the discovery of the spectra, scientists had tried to find ways to catergorize stars. By observing spectra , astronomers realized that the large numbers of stars exhibit a small number of distinct patterns in their spectral lines. Classification by the spectral features quickly proved to be a powerful tool for understanding stars. The current spectral classification scheme was developed at Harvard Observatory in the early 20th century. Work was begun by Henry Draper who photographed the first spectrum of Vega in 1872. After his death, his wife donated the equipment and a sum of money to the Observatory to continue his work. The bulk of classification work was done by Annie Jump Cannon from 1918 to 1924. The original scheme used capital letters running alphabetically, but the subsequent revisions have reduced this as stellar evolution and typing has become better understood. The work was published in the Henry Draper Catalog and Henry Draper Extension which contained spectra of 225,000 stars down to ninth magnitude. The scheme is based on lines which are mainly sensitiveto stellar surface tempertures rather than actual composition differences,gravity, or luminosity. Inportant lines

Why Animal Rights Activists Oppose Aquariums

Why Animal Rights Activists Oppose Aquariums Animal rights activists oppose aquariums for the same reason they oppose zoos. Fish and other sea creatures, like their land-dwelling relatives, are sentient and have a right to live free from human exploitation. In addition, there are concerns about the treatment of the animals in captivity, especially marine mammals. Aquariums and Animal Rights From an animal rights perspective, keeping animals in captivity for our own use is an infringement on that animals right to be free of human exploitation, regardless of how well the animals are treated. There are some people who doubt the sentience of fish and other sea creatures. This is an important issue because the rights of animals are based on sentience - the ability to suffer. But studies have shown that fish, crabs, and shrimp do feel pain. What about anemones, jellyfish and other animals with simpler nervous systems? While its debatable whether a jellyfish or anemone can suffer, it is clear that crabs, fish, penguins and marine mammals do feel pain, are sentient and are therefore deserving of rights. Some might argue that we should give jellyfish and anemones the benefit of the doubt because there is no compelling reason to keep them in captivity, but in a world where clearly intelligent, sentient beings such as dolphins, elephants and chimpanzees are kept in captivity for our amusement/education, the main challenge is convincing the public that sentience is the determining factor for whether a being has rights, and sentient beings should not be kept in zoos and aquariums. Aquariums and Animal Welfare The animal welfare position holds that humans have a right to use animals as long as the animals are treated well. However, even from an animal welfare viewpoint, aquariums are problematic. Animals in an aquarium are confined in relatively small tanks and can get bored and frustrated. In an effort to provide more natural environments for the animals, different species are often kept together, which lead to predatory animals attacking or eating their tank mates. Furthermore, the tanks are stocked either with captured animals or animals bred in captivity. Capturing animals in the wild is stressful, injurious and sometimes fatal; breeding in captivity is also a problem because those animals will live their entire lives in a tiny tank instead of a vast ocean. Special Concerns About Marine Mammals There are special concerns regarding marine mammals because they are so large and they so obviously suffer in captivity, regardless of any educational or entertainment value they may have for their captors. This is not to say that marine mammals suffer more in captivity than small fish, although that is possible, the suffering of marine mammals is more obvious to us. For example, according to the World Society for the Protection of Animals, a dolphin in the wild swims 40 miles per day, but US regulations require dolphin pens to be only 30 feet in length. A dolphin would have to circle his tank more than 3,500 times every day to simulate his natural range. Regarding killer whales in captivity, the Humane Society of the US explains: This unnatural situation can cause skin problems. In addition, in captive killer whales (orcas), it is the probable cause of dorsal fin collapse, as without the support of water, gravity pulls these tall appendages over as the whale matures. Collapsed fins are experienced by all captive male orcas and many captive female orcas, who were either captured as juveniles or who were born in captivity. However, they are observed in only about 1% of orcas in the wild. And in rare tragedies, captive marine mammals attack people, possibly as a result of post-traumatic stress syndrome after being captured from the wild. What About Rehabbing or Public Education? Some might point out the good work that aquariums do: rehabbing wildlife and educating the public about zoology and ocean ecology. While these programs are laudable and certainly not trivial, they cannot justify the suffering of the individuals in aquariums. If they operated as true sanctuaries for individual animals who cannot return to the wild, such as Winter, the dolphin with a prosthetic tail, there would be no ethical objections. What Laws Protect Animals in Aquariums? On the federal level, the federal Animal Welfare Act covers the warm-blooded animals in aquariums, such as marine mammals and penguins, but does not apply to fish and invertebrates - the vast majority of animals in an aquarium. The Marine Mammal Protection Act offers some protection for whales, dolphins, seals, walruses, sea lions, sea otters, polar bears, dugongs, and manatees, but does not prohibit keeping them in captivity. The Endangered Species Act covers endangered species that might be in an aquarium and applies to all types of animals, including marine mammals, fish, and invertebrates. Animal cruelty statutes vary by state, and some states may offer some protection to the marine mammals, penguins, fish and other animals in aquariums. The information on this website is not legal advice and is not a substitute for legal advice. For legal advice, please consult an attorney.