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Large Magellanic Cloud

The Large Magellanic Cloud is a satellite galaxy of the Milky Way. At a distance of about 50 kiloparsecs, the LMC is the second- or third-closest galaxy to the Milky Way, after the Sagittarius Dwarf Spheroidal and the possible dwarf irregular galaxy known as the Canis Major Overdensity. Based on visible stars and a mass of 10 billion solar masses, the diameter of the LMC is about 14,000 light-years, making it one one-hundredth as massive as the Milky Way; this makes the LMC the fourth-largest galaxy in the Local Group, after the Andromeda Galaxy, the Milky Way, the Triangulum Galaxy. The LMC is classified as a Magellanic spiral, it contains a stellar bar, geometrically off-center, suggesting that it was a barred dwarf spiral galaxy before its spiral arms were disrupted by tidal interactions from the Small Magellanic Cloud and the Milky Way's gravity. With a declination of about −70°, the LMC is visible as a faint "cloud" only in the southern celestial hemisphere and from latitudes south of 20° N, straddling the border between the constellations of Dorado and Mensa, appears longer than 20 times the Moon's diameter from dark sites away from light pollution.

The Milky Way and the LMC are expected to collide in 2.4 billion years. Although both clouds have been visible for southern nighttime observers well back into prehistory, the first known written mention of the Large Magellanic Cloud was by the Persian astronomer'Abd al-Rahman al-Sufi Shirazi, in his Book of Fixed Stars around 964 AD; the next recorded observation was in 1503–1504 by Amerigo Vespucci in a letter about his third voyage. In this letter he mentions "three Canopes, two bright and one obscure". Ferdinand Magellan sighted the LMC on his voyage in 1519, his writings brought the LMC into common Western knowledge; the galaxy now bears his name. Measurements with the Hubble Space Telescope, announced in 2006, suggest the Large and Small Magellanic Clouds may be moving too fast to be orbiting the Milky Way; the galaxy and southern end of Dorado are in the current epoch at opposition on about 5 December when thus visible from sunset to sunrise from equatorial points such as Ecuador, the Congos, Uganda and Indonesia and for part of the night in nearby months.

Below about 28° south the galaxy is always sufficiently above the horizon to be considered properly circumpolar, thus spring and autumn are seasons of much-of-night visibility, the height of winter in June nearly coincides with closest proximity to the Sun's apparent position. The Large Magellanic Cloud has a spiral arm; the central bar seems to be warped so that the east and west ends are nearer the Milky Way than the middle. In 2014, measurements from the Hubble Space Telescope made it possible to determine that the LMC has a rotation period of 250 million years; the LMC was long considered to be a planar galaxy that could be assumed to lie at a single distance from the Solar System. However, in 1986, Caldwell and Coulson found that field Cepheid variables in the northeast portion of the LMC lie closer to the Milky Way than Cepheids in the southwest portion. More this inclined geometry for field stars in the LMC has been confirmed via observations of Cepheids, core helium-burning red clump stars and the tip of the red giant branch.

All three of these papers find an inclination of ~35°, where a face-on galaxy has an inclination of 0°. Further work on the structure of the LMC using the kinematics of carbon stars showed that the LMC's disk is both thick and flared. Regarding the distribution of star clusters in the LMC, Schommer et al. measured velocities for ~80 clusters and found that the LMC's cluster system has kinematics consistent with the clusters moving in a disk-like distribution. These results were confirmed by Grocholski et al. who calculated distances to a number of clusters and showed that the LMC's cluster system is in fact distributed in the same plane as the field stars. The distance to the LMC has been calculated using a variety of standard candles, with Cepheid variables being one of the most popular. Cepheids have been shown to have a relationship between their absolute luminosity and the period over which their brightness varies. However, Cepheids appear to suffer from a metallicity effect, where Cepheids of different metallicities have different period-luminosity relations.

The Cepheids in the Milky Way used to calibrate the period–luminosity relation are more metal-rich than those found in the LMC. Modern 8-meter-class optical telescopes have discovered eclipsing binaries throughout the Local Group. Parameters of these systems can be measured without compositional assumptions; the light echoes of supernova 1987A are geometric measurements, without any stellar models or assumptions. In 2006, the Cepheid absolute luminosity was re-calibrated using Cepheid variables in the galaxy Messier 106 that cover a range of metallicities. Using this improved calibration, they find an absolute distance modulus of 48 kpc; this distance has been confirmed by other authors. By cross-correlating different measurement methods, one can bound the distance; the results of a study using late-type eclipsing binaries to determine the distance more was published in the scientific journal Nature in March 2013. A distance of 49.97 kpc with an accuracy

West Virginia's 3rd Senate district

West Virginia's 3rd Senate district is one of 17 districts in the West Virginia Senate. It is represented by Republicans Donna Boley and Mike Azinger. All districts in the West Virginia Senate elect two members to staggered four-year terms. District 3 covers much of the Mid-Ohio Valley region, including all of Pleasants and Wood Counties and parts of Roane County, it is based in the city of Parkersburg covering the nearby communities of Vienna, Blennerhassett, Elizabeth, St. Marys; the district is located within West Virginia's 1st congressional district, with a small portion extending into West Virginia's 2nd congressional district, overlaps with the 6th, 7th, 8th, 9th, 10th, 11th districts of the West Virginia House of Delegates. It borders the state of Ohio. In 2016, both seats were up for election due to an unusual series of events. Republican Bob Ashley, appointed to the Senate following the departure of David Nohe in 2015, chose to run in a primary against his fellow senator Donna Boley, leaving his own seat open and triggering a special election

Prehensile tail

A prehensile tail is the tail of an animal that has adapted to grasp or hold objects. Prehensile tails can be used to hold and manipulate objects, in particular to aid arboreal creatures in finding and eating food in the trees. If the tail cannot be used for this it is considered only prehensile - such tails are used to anchor an animal's body to dangle from a branch, or as an aid for climbing; the term prehensile means "able to grasp". One point of interest is the distribution of animals with prehensile tails; the prehensile tail is predominantly a New World adaptation among mammals. Many more animals in South America have prehensile tails than in Southeast Asia, it has been argued that animals with prehensile tails are more common in South America because the forest there is denser than in Africa or Southeast Asia. In contrast, less dense forests such as in Southeast Asia have been observed to have more abundant gliding animals such as colugos or flying snakes. South American rainforests differ by having more lianas, as there are fewer large animals to eat them than in Africa and Asia.

Curiously, Australia-New Guinea contains many mammals with prehensile tails and many mammals which can glide. Tails are a feature of vertebrates. However, only vertebrates are known to have developed prehensile tails. Many mammals with prehensile tails will have a bare patch to aid gripping; this bare patch is known as a "friction pad". New World monkeys. Many New World monkeys in the family Atelidae, which includes howler monkeys, spider monkeys and woolly monkeys, have grasping tails with a bare tactile pad; this is in contrast with their distant Old World monkey cousins. Opossum. A marsupial group from the Americas. Video evidence exists of opossums using their prehensile tails to carry nesting material. Anteaters. Anteaters are found in South America. Three of the four species of anteater, the silky anteater and the two species of tamandua, have prehensile tails Binturong. One of the few Old World animals with prehensile tails, although they use only the tip of the tail. Kinkajou; the kinkajou of South and Central America is the only other animal of the order Carnivora, besides the binturong, to sport the adaptation.

Harvest mouse. Another old world mammal, the harvest mouse has a prehensile tail, it is found amongst areas of tall grasses such as cereal crops, roadside verges, reedbeds and salt-marshes. New World porcupines of the genera Coendou and Chaetomys have prehensile tails that help them to climb and prevent them from falling from trees. Tree pangolin. One of the few Old World mammals with a prehensile tail. Microgale longicaudata, an arboreal species of tenrec. Seahorses. Seahorses have prehensile tails, which they use to attach themselves to objects such as seagrass, sponges, corals, or man-made objects. New World monkeys; the capuchin monkey. The capuchin is more than intelligent enough to make full use of its prehensile tail, but since the tail lacks an area of bare skin for a good grip it is only used in climbing and dangling. Other reasons for partial prehensility might include the lack of strength or flexibility in the tail, or having no need to manipulate objects with it. Tree porcupines; the 15 species of tree porcupine.

They are found with one species extending to Mexico. All have prehensile tails. Rats have been known to be able to wrap the tail around an object after running around it, therefore giving the creature a small bit of balance, they have been seen to be able to hang off an object, though not for long. Possums; this large, diverse group of 63 species forms the marsupial suborder Phalangeriformes, found in Australia, New Guinea, some nearby islands. All members of the suborder have prehensile tails. Notably, all three marsupial glider groups belong to this suborder. Potoroidae. A marsupial group found in Australia that includes the potoroos, they have weakly prehensile tails. Monito del monte. A small South American marsupial with a prehensile tail. Prehensile-tailed skink. Several kinds of skink have prehensile tails. Chameleon lizards. Snakes. Many snakes have prehensile tails Crested gecko and their relatives have prehensile tails Urocoyledon rasmusseni. A gecko discovered in the Udzungwa mountains. Alligator lizard.

Some alligator lizards such as the southern alligator lizard, the Texas alligator lizard, the arboreal alligator lizards have prehensile tails. Salamanders. A number of North American forest-dwelling climbing salamanders have prehensile tails that help them climb; some are from the genus Aneides such as the clouded salamander, the wandering salamander, the arboreal salamander. Others are the cave salamander. There are the Central American Bolitoglossa sombra and Mexican and Central American Bolitoglossa mexicana salamanders. Syngnathidae. Many species from this group, which includes seahorses and pipefish, have prehensile tails. Canopy life More on canopy life