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Melting Pot free essay sample

The blend has been utilized figuratively to portray the elements of American public activity. Notwithstanding its engaging uses, it has like...

Thursday, March 26, 2020

Astronomers Peer Deep into Blobs in Space

Astronomers Peer Deep into Blobs in Space Out in the depths of space, theres a blob that astronomers have been anxious to explain. It wasnt immediately obvious to them why it shined as brightly as it did. The blob (and it really is a blob) is called SSA22-Lyman-alpha-blob and it lies some 11.5 billion years away from us. That means that it looks to us now as it did some 11.5 billion years ago. SSA22-LAB appears to have two giant galaxies at its heart that are bursting with star formation activity. The whole region where this object and its galaxies lies is swarming with smaller galaxies. Clearly, something is going on there, but what?   VLT and ALMA to the Rescue This rare Lyman-alpha Blob is not exactly visible to the naked eye. Thats largely due to distance, but also because the light its emitting is visible to us here on Earth in infrared wavelengths and also in radio frequencies. The name Lyman-alpha-blob tells astronomers that the object originally radiated its light in ultraviolet wavelengths. However, due to the expansion of space, the light is shifted so that its visible in infrared. Its one of the largest of these LABs to be observed. So, astronomers used the European Southern Observatorys  Very Large Telescope Multi Unit Spectroscopic Explorer to dissect the incoming light for study. They then combined that information with data from the Atacama Large-Millimeter Array (ALMA) in Chile. Together, these two observatories allowed astronomers to peek into the heart of the action at the distant blob in space. Deep imaging with the Hubble Space Telescopes Imaging Spectrograph and the W.M. Keck Observatory in Hawaii also helped them refine the view of the blob. The result is an amazingly beautiful view of a blob that existed in the distant past but is still telling us its story today. Whats Happening at SSA22-LAB? It turns out that this blob is one very interesting result of galaxy interactions,  which create ever-larger galaxies. Furthermore, the two embedded galaxies are surrounded by clouds of hydrogen gas. At the same time, they are both cranking out hot young stars at a furious rate. Baby stars emit a lot of ultraviolet light, and that lights up the surrounding clouds. Its like looking at a streetlight on a foggy night - the light from the lamp scatters off the water drops in the fog and it makes a kind of foggy glow around the light. In this case, the light from the stars is scattering off the hydrogen molecules and creating the lyman-alpha blob. Why Is This Discovery so Important? Distant galaxies are extremely interesting to study. In fact, the more distant they are, the more fascinating they get. Thats because very distant galaxies are also very early galaxies. We see them as they were as they were infants. The birth and evolution of galaxies is one of the hottest areas of study in astronomy these days. Astronomers know that it proceeds as smaller galaxies merge together with larger ones. They see galaxy mergers at nearly every part of cosmic history, but the beginnings of those mergers started back 11 to 13 billion years ago. However, the details of all mergers are still being studied, and the results (such as this lovely blob) are often quite a surprise to them. If scientists can get a handle on how galaxies form through collisions and cannibalization, they can understand how these processes worked in the early universe. Whats more, from observing other, newer galaxies that have been through the same process that this LAB galaxy is experiencing, they know that it will result in a giant elliptical galaxy. Along the way, it will collide with more galaxies. Each time, the galaxy interaction will force the creation of countless hot, young massive stars.  These starburst galaxies show prodigious rates of star formation. And, as they evolve and die, they will also change their galaxy - seeding it with more elements and the seeds of future stars and planets. In a sense, looking at SSA22-Lyman-alpha-blog is like looking at the process our own galaxy might have experienced early in its formation. However, the Milky Way didnt end up as an elliptical galaxy in the heart of a cluster as this one will do. Instead, it became a spiral galaxy, home to trillions of stars and many planets. ​In the future, it will merge again, this time with the Andromeda Galaxy. And, when it does that, the combined galaxies will indeed form an elliptical. So, the study of SSA22-LAB is a very important step in understanding the origin and evolution of all galaxies.

Friday, March 6, 2020

Medea in the hellenic age essays

Medea in the hellenic age essays In todays society people are from different cultures and social backgrounds. Your culture may determine your values and the way you should act. Many people judge others cultures on the sole basis of their culture. Sometimes conflicts occur when cultures clash. Different cultures fights or even worse wars may submerge from them fighting. In Greek history there were many ages and peoples culture and value system changed over the times. The Greek culture was the first to look at human beings as the source of themselves. They no longer saw mortals as the inconsequential objects of divine whim.(WH p 31) They saw themselves as having some control over their responsibilities and moral accountability for their actions. The Greek philosopher Protagoras stated that Man is the measure of all things. Thinking this way the Greeks was more successful in creativity reaching heights they never thought they would reach. Their culture developed in the Aegean Sea were, trading, conquest and expansion was possible. The Greeks traded goods with the Egyptians and the Hittites of Anatolia. They borrowed and adapted a writing system from the Phoenicians. They learned sculptural techniques from the Egyptians and other teachings such as working with metal and clay, music and mathematics, and elements of their religious system from other Eastern civilization. The Greek thrived in the Aegean basin. with Minoan and the Mycenaean who left a mark on the Greeks. With the defeat of Persians at Plataea in 479 B.C., the Greeks entered the Hellenic age. This age lasted until Alexander the great died in 323 B.C. The Hellenic age was the first stage of classic civilization.(WH p55) It was one of the Greeks highest achievements. The Greeks still lived in countryside but the city now dominates politics, society and the economy. Attitudes toward Olympian were getting better and public work ship developed into festivals. The g ...