The Origins Of Theatre And Playwrights English Literature Essay

The Origins Of Theatre And Playwrights English Literature Essay This essay aims to discuss the effectiveness of political theatre in causing social change, looking specifically at the practice of the contemporary political playwright Augusto Boal including the influence of social theorist Karl Marx on Boals work and how Marxism affected Boals style of theatre. This essay will begin by looking at the origins of theatre and how it has been used since then as a medium of promoting political thought. However, in order to understand political theatre we must first be able to understand what is mean by politics, the Oxford Reference Dictionary (1991:647) describes something political as affecting the State or its Government; of public affairs. From this definition we are able to deduce that political theatre is theatre that is produced in order to affect or influence the community and those in power with regard to public affairs. This type of theatre has been used and enjoyed since the very beginning of theatre as we know it today, which began in Ancie nt Greece in the celebration of the festival of Dionysos, the God of ecstasy. The festival included prayer and procession as well as singing and dancing, there may also have been groups of performers who would answer each other through the medium of song or dance. It is believed that it was Thespis who stood out and performed first without the chorus, and thus creating what we understand to be a protagonist. (GREEK THEATRE 1) Competitions then began to take place during the festivals in which playwrights would enter their plays to be performed, either a tragedy, or a comedy and satyr play. The Greek playwrights would present the audience with ideas to think about and reflect over; during the plays a Parabasis, or stepping aside would take place, this was an opportunity for the playwright to comment upon the state of city affairs or anything else that he so wished. Aristophanes thought that, the dramatist should not only offer pleasure but should, besides that, be a teacher of morali ty and a political advisor.(in Boal 2008:xiii) In his plays, Aristophanes would satirise the most important people of the day, in between the scenes the chorus would perform short, satirical pieces of song and dance always attacking well known individuals by name, for example he ridiculed the demagogue Kleon in his play Babylonians. However, a plays success depended on the funding from the wealthy aristocracy ay the time, the choragus therefore the plays produced may be seen to reflect the view of the choregus rather than that of the playwright, because without them a play would not have the funding to be performed. Greek society was much controlled by the economic minority, the Bourgeoisie, but nothing was done to change this. This state of affairs in Ancient Greece is very similar to the social situation that Karl Marx was fighting against when he introduced his communist manifesto; the alternative to capitalism. Marx believed that human beings have been conditioned throughout his tory to behave a certain way by economic institutions and that in order for an equal society without a social hierarchy then the proletariat must seize power from the bourgeoisie through a social revolution and place everything in collective ownership. In his book Theatre of the Oppressed Augusto Boal writes how Marx believed that art is a key way of offering knowledge, but this knowledge is conveyed from the perspective of the artist, social surroundings or whoever provides sponsorship or payment. Mainly, it is the part of society that maintains economic power that holds control over any means of communication. Bordwell and Thompson (in Woodson, no date) back this up: Each art form is controlled, not by the artists, but by larger social institutions. In a capitalist society, an artist may believe he or she is using the art form for personal expression, but he or she is actually producing merchandise of a kind acceptable to the society. It is only from the arrival of Karl Marx and his theories on socialism that playwrights and practitioners have begun to use theatre as a means for change. Bertolt Brecht was greatly influenced by the Marxist theory because he too wanted to create change, the major goal of the historical avant-garde was to challenge the institution of bourgeois art (Kistenberg 1995:29); Pescator described Brechts work as a Marxist-based analysis of social relations. Brecht agreed with Marx that it was the capitalists that created the bourgeois society, and that drama can be used as a medium of didacticism. It was from this belief that Brecht adopted Piscators form of avant-garde theatre known as epic theatre. Epic theatre has many parallels with Cartesian tradition in which people are encouraged into rational thought; it underlines the socio-political content of drama rather than trying to manipulate the emotions of the audience. Brecht stated that there must be a transformation of psychological confl ict into historic condition (in Basuki no date) in theatre in order to release the self and to create rational thought. This Cartesian belief is needed so that neither the audience nor the actor tries to empathise with the action and characters on stage and are able to view the action with a critical mind. In order to do this Brecht proposed that theatre needed to give to the audience a process of alienation because alienation is necessary to all understanding (Brecht in Basuki no date) so that they are able to form an opinion unfettered by empathy. The term Brecht used to describe this distancing of the audience is Verfremdungseffekt, which when translated, means alienation. In a description about epic theatre Brecht gives an explanation about the difference between a spectator watching dramatic theatre and one watching epic theatre: The dramatic theatres spectator says: Yes, I have felt like that too-Just like me-Its only natural-Itll never change-The suffering of this man appals me, because they are inescapable-Thats great art; it all seems the most obvious thing in the world-I weep when they weep, I laugh when they laugh. The epic theatres spectator says: Id never have thought it-thats not the way-Thats extraordinary, hardly believable-Its got to stop-The sufferings of this man appal me, because they are unnecessary-Thats great art: nothing obvious in it-I laugh when they weep, I weep when they laugh (Brecht in Basuki no date) This quote from Brecht shows us how he intended epic theatre to work and its popularity among playwrights and directors is a great example of how successful epic theatre is as a form of didacticism. However, in Brechts plays the separation between the stage and the audience is still present. The spectator is persuaded to think the thoughts and opinions that presented to them through the action on stage because it is the playwrights who condemns the characters or the events that have taken place; the audiences thoughts are merely pointed in the right direction by the dramatist (OPPRESSED xx) Augusto Boal, though highly influenced by the likes of Marx and Brecht took the format of epic theatre to a new level. He found ways of combining Marxist theory with new ways of writing and analysis. He believed that in order to liberate the audience from the constraints of stage and spectator, they themselves must be part of what is happening on stage To transform is to be transformed.(Boal 2008: xxi) and thus becoming spect-actors. From this belief Boal created the Theatre of the Oppressed in which the audience are asked to intercede, and suggest the next course of action for the actors to perform or actually perform themselves, whilst the actors assist and persuade the audience to take the role of a spect-actor. For example, in forum theatre, the actors perform a short play with which ends with unresolved oppression and then it is performed again but this time the spect-actor is able to become involved and suggest ways to fix the oppression. Boal saw the spectators invasion of the stage as a symbolic moment in their transformation, This invasion is a symbolic trespass. It symbolises all the acts of trespass we have to commit in order to free ourselves from what oppresses us. (Boal 2008:xxi) By doing this the spect-actor is made aware of what he needs to do in order to change the situation in his real social setting, and by breaking down the wall between spectator and acto r, Boal also breaks the wall between the oppressor and the oppressed. (BOAL ESSAY) English Theatre company Cardboard citizens is one of the leading producers of Forum Theatre in the UK, this company is made up of homeless people or those at risk of becoming homeless. Cardboard Citizens tour the UK, performing for other Homeless people, and as it states on their website, aiming to problem-solve together. (CARDBOARD WEBSITE) Although this is an excellent way of trying to create social change, it may be the case that the company perform to an audience who are already aware of the situation being presented to them, and are therefore preaching to the converted. In The Transparent Closet: Gay Theatre for Straight Audiences, Richard Hall (in Kistenberg 1995:76) suggests: Theatre is inefficient as an instrument for social change. It either speaks to those already in support of its views, or to those who are so secure in their power that they dont mind hearing themselves abused, as long as the abuse is entertaining. Although theatre is an excellent form of communication, it is unable to access the parts of society in which people do not watch theatre that is seen to be anything other than mainstream entertainment i.e. Musicals etc. This then stops the theatre from being its most effective. As well as this, political theatre may become an outlet for people to confirm their opinions, for example, David Hares play Stuff Happens was written as a reaction to the Iraq War, somebody who has negative beliefs about this event may watch the play just so their opinions are confirmed. This again may stop the theatre from being at its most effective. Although Cardboard Citizens use of forum theatre has helped many homeless peoples situations and is working to gain understanding of the struggles homeless people encounter, Elizabeth Burns states that the audience view themselves as part of a performance rather than performance as part of their lives (in Kistenberg 1995:32) She believes that the audience are me rely props for the actors and that because they are in a state of being neither fully part of the performance nor full separate then it isnt much different from their usual role as spectator. If this is the case then the spectators of Cardboard Citizens performances, even if they were able to present their theatre to a much wider and varied kind of audience, would not be much changed by what they have seen. Boals next step in creating social change could be seen to have a great impact on society, he generated a form of theatre named Legislative Theatre in which theatre is used to create an active and practical change in society. Boal ran for election and was voted in to be one of 42 vereadores  of Rio, (BOAL ESSAY) he used his new political position to create Legislative Theatre. In this type of theatre Boal attempted To use theatre within a political system to create a truer from of democracy (Boal 2008:i) This type of theatre uses all the techniques of the theatre of the oppressed in order to create new laws, Boal would take his theatre to the streets of Rio and asked the people what they thought of certain issues then proposed his findings to the council chamber. In this way he was able to put forward laws to be passed that had a significant impact on the people of Rio, for example, one law that was passed was one which protected the witnesses of crimes. (LEGISLATIVE THEATRE 104). Theatre is not just about entertaining the masses; it provides a means in which to get a message across. Although all of theatre could be said to be political in a broader sense, it is political theatre that has been established as designing a theatre that is left wing and that expresses the need for radical change. Political theatre has thrived under oppressive governments as a means of communicating political opinions; however this has not always been the case. In spite of how seemingly political Greek theatre appears the censorship of the plays provides evidence towards the fact that it was not and it did little to challenge and change the social hierarchy of the time because it was controlled by the people in power. Greek theatre started by being interactive and an open form of communication; however the right to speak was taken away when the citizens were split into chorus and audience. It is seemingly ironic then that it was someone speaking out of turn that first created this form of theatre but by being made to be the audience the rest were stifled. Looking back at how political theatre has developed over the years it is clear of the relevance of each individual practitioner at the respective times in which they were writing, for example, in the years of extreme censorship by the Bourgeoisie when Brecht was writing he was one of the first practitioners to use theatre to make people aware of their situation therefore enlightening them because it was the first time they had been shown the truth. However now, in the 21st Century when people are able to access, via the means of the internet for example, all types of imformation without censorship they are given the opportunity through practices such as Boals to actively change society. Boals Legislative Theatre encapsulates the aim of political theatre. As Brecht used Epic theatre in order to create social change, Boal took his format and physically created change through the placement of new laws. This is ultimately the aim of political theatre, to release the oppressed from the op pressor. Conclusion. Zortman (2) says that The avant-garde artists were denounced as breeders of the proletarian world revolution Quotes 356 / 1403words.

Ecological Threats Essay

A cycle is a series of change which comes back to the starting point and which can be repeated.[1][2] The term â€Å"biogeochemical† tells us that biological, geological and chemical factors are all involved. The circulation of chemical nutrients like carbon, oxygen, nitrogen, phosphorus, calcium, and water etc. through the biological and physical world are known as biogeochemical cycles. In effect, the element is recycled, although in some cycles there may be places (called reservoirs) where the element is accumulated or held for a long period of time (such as an ocean or lake for water).[1][2] Water, for example, is always recycled through the water cycle, as shown in the diagram. The water undergoes evaporation, condensation, and precipitation, falling back to Earth clean and fresh. Elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another through the biogeochemical cycles. Systems Chloroplasts conduct photosynthesis and are found in plant cells and other eukaryotic organisms. These are Chloroplasts visible in the cells of Plagiomnium affine — Many-fruited Thyme-moss. Ecological systems also known as ecosystems have many biogeochemical cycles operating as a part of the system, for example the water cycle, the carbon cycle, the nitrogen cycle, etc. All chemical elements occurring in organisms are part of biogeochemical cycles. In addition to being a part of living organisms, these chemical elements also cycle through abiotic factors of ecosystems such as water (hydrosphere), land (lithosphere), and/or the air (atmosphere).[3] The living factors of the planet can be referred to collectively as the biosphere. All the nutrients—such as carbon, nitrogen, oxygen, phosphorus, and sulfur—used in ecosystems by living organisms are a part of a closed system; therefore, these chemicals are recycled instead of being lost and replenished constantly such as in an open system.[3] The flow of energy in an ecosystem is an open system; the sun constantly gives the planet energy in the form of light while it is eventually used and lost in the form of heat throughout the trophic levels of a food web. Carbon is used to make carbohydrates, fats, and proteins, the major sources of food energy. These compounds are oxidized to release carbon dioxide, which can be captured by plants to make organic compounds. The chemical reaction is powered by the light energy of the sun. It is possible for an ecosystem to obtain energy without sunlight. Carbon must be combined with hydrogen and oxygen in order to be utilized as an energy source, and this process depends on sunlight. Ecosystems in the deep sea, where no sunlight can penetrate, use sulfur. Hydrogen sulfide near hydrothermal vents can be utilized by organisms such as the giant tube worm. In the sulfur cycle, sulfur can be forever recycled as a source of energy. Energy can be released through the oxidation and reduction of sulfur compounds (e.g., oxidizing elemental sulfur to sulfite and then to sulfate). Although the Earth constantly receives energy from the sun, its chemical composition is essentially fixed, as additional matter is only occasionally added by meteorites. Because this chemical composition is not replenished like energy, all processes that depend on these chemicals must be recycled.

Allergies and other type of immune hypersensitivities

Allergies and other type of immune hypersensitivities are important undesirable side effect of our immune system. These problems occur in people who have a specific allergic tendency. Anyone suffering from allergy can take comfort that there are over 50 million fellow American sufferers of this problem. Roughly one in 6 American is afflicted with allergic problem. Fortunately, in very few people allergic condition can become life threatening.In most allergy sufferers problems due to allergy appear to be trivial such as runny nose, sneezing, itchy eyes, sinus problem, rash and skin complaints but these otherwise minor problems can make the allergy sufferers lives quite miserable. Our immune system, essential for defending our bodies against foreign organisms, produces antibodies and activated white cells to attack invaders like viruses and bacteria. Occasionally, the immune response results in an inappropriate or exaggerated reaction called hypersensitivity. Hypersensitivity is classi fied into four types; Types I, II, III and IV.Types I to Type III hypersensitivities are antibody-mediated while Type IV is a cell mediated hypersensitivity. Type II & III are Immunoglobulin G (IgG) mediated while Type I sensitivity is Immunoglobulin E mediated. The term ‘Allergy’ is confined to IgE mediated reactions or Type I hypersensitivity [Levinson, 2004] . Immunoglobulin E (IgE) is our body’s host defense system against certain parasites such as worms. In developed countries, where parasitic infection is uncommon, most people have no or very low level of IgE.An allergic reaction or allergy occurs when our body’s immune system mistakenly considers a harmless substance, called ‘allergen’ as dangerous and starts producing IgE to trigger an allergic reaction [Levinson, 2004]. Types of Allergies Allergic Rhinitis: This type of allergy causes swelling of nasal mucosa with respiratory discomforts like sneezing and runny nose by inhaling allerg ens such as pollen, molds, dust, dander and other allergens. Allergic Conjunctivitis: The allergic reaction affects the eyes, redness and itching are the signs of this allergy. Bronchoconstriction:Wheezing and shortness of breath caused by narrowing of bronchial cavities. Asthma is a serious type of bronchoconstriction. This type of allergy is also caused dust, pollen, mites, and other allergens. Ear Allergies: The allergens affect ear passages causing pain and impairing hearing. Skin Allergies: Itchy rashes, blisters, hives, and contact dermatitis caused by touching certain substances such a poison ivy or food items are manifestation of this type of allergy. In allergies where swelling occurs as a result of hives, swelling can cause breathing and swallowing difficulties. Food Allergies:Certain kind of foods, such as fish egg, nuts and milk can cause intestinal upsets due to allergic reactions. Time Delayed Allergies: An allergic response appearing hours or days after application or absorption of an allergen; including contact dermatitis and bacterial allergy [Allergies, 2006] Anaphylaxis: This is the most severe systemic allergic reaction causing bronchoconstriction, swelling of body tissues, vomiting, cramps, skin reactions and drop in blood pressure, coma and even death [Guyton & Hall, 2006]. Allergy can also be classified on the basis of its effect and allergen as:? Respiratory Allergies ? Skin Allergies ? Food Allergies ? Asthma ? Drug Allergies ? Sting Allergies Causes & Risk Factors Problems with normal immune responses are believed to be the result of both genetic and environmental factors. Children of allergic parents are more likely to have similar allergies though the allergens may differ. [Allergies, 2006] Genetic research is leading scientists to believe that skin and tissue specific genes may be responsible for causing allergy symptoms [NIH, 2000]. Stress and anxiety are acknowledged a common cause of allergic reaction.[Lenzoff, 1997] subjected p atients suspected of multiple chemical sensitivities concluded that in some sufferers allergy symptoms might be triggered by their perception of an environmental insult. Increasing use of chemicals has resulted in introduction of new toxins into the atmosphere. The increase in number of allergy cases during the last decades is often attributed to atmospheric pollution [Bornehag et al, 2004]. Better identification of problem as allergy and not other minor condition such as cold is perhaps also responsible for increased numbers. Allergy or ColdA number of symptoms of common cold are also the symptoms of allergy. It is not unusual to mistake one for the other. The major difference between the cold and flu are [Allergy, 2006b]: – Both cold and allergy show the common symptoms of allergy but the cold is also accompanied by fever and pain. – Allergy begins immediately after exposure to the allergen while cold takes a day or more to develop to full strength. – Cold is a self terminating diseases and the symptoms disappear in 3 to 7 days while allergies continue till the person remains exposed to the allergen AllergensThe body’s immune system has the capability to attack a foreign organism. If it identifies a substance such as pollen as foreign, even mistakenly, the defense mechanism comes into action and IgE is produced to fight off that particular substance. Thus, there will be separate IgE for pollen and for dust allergies. There are many allergens as any person could be allergic to a common substance, which is not an allergen to others, but the common allergens include pollen and fungus from weeds, grasses. Trees and outdoor mold, dog and cat dander, dust particles, noxious vapors and smog, foods such as fish, eggs, nuts and insect bites.Signs & Symptoms In addition to the usual sneezing, runny nose, rashes allergy and red or itchy eyes symptoms include atopic dermatitis, contact dermatitis, headache, earache, hives, coughing, sinusitis , and other discussed above. Medical Tests & Diagnosis Methods/Tools The diagnostic tests for Allergy include: †¢ Skin Prick Test (SPT) †¢ Total IgE Test †¢ Range of Specific IgE Test †¢ Phadiatop Assay †¢ Specific IgE Pediatric Food Mix fx5 Skin Prick Test: Skin prick test is a common and simple method of diagnosing allergy.In this test small amount of suspected allergens are injected either intra-dermally or into the scratching made in the patient’s skin. Patient allergic to any of the allergen shows a visible inflammation after half an hour. Skin Prick Test (SPT) only responds to allergens used in the test. In cases where patient is allergic to any other allergen, this test will not show. Some patients with delayed type hypersensitivity may be adversely affected by the test. Total IgE Test: Patient serum IgE test is another method used for determining Type I hypersensitivity.The test provides useful indication for allergy. This test however is not considered conclusive. The test measures total IgE value and is said to be only to report existence of allergy 60% of the time [Labspec, 2006]. The extent of symptoms and type of allergy has an effect on the result. Severe skin allergy shows a higher IgE value than rhinitis or conjunctivitis. [Labspec, 2006] also point out that Standard IgE values appear to vary with ethnicity of the patient. Range of Specific IgE Test: Some diagnostic suppliers are manufacturing specific IgE test for allergens.Specific tests for over 400 allergens are available. Some of these specific tests have been approved for routine tests, other are awaiting approval. [Labspec, 2006] Phadiatop Assay: Instead of testing total IgE or specific test for a single allergen, this test tests serum for a wide range of inhalant allergens. The test is said to be 95% reliable and can be used to exclude allergens included in Phadiatop assay. Specific IgE Pediatric Food Mix fx5 His test is similar to Phadiatop Assay, but in stead of inhalant allergens, ingestant allergens are tested.This test is still in approval stages for general laboratory use. Treatment Options Many people with mild allergies avoid seeking medical help, but it is important to know that allergies if left untreated can develop into serious health problems like infections in sinuses, throat and ears, chronic respiratory problems, skin problems such as eczema. The treatment Options for allergies include: †¢ Avoid allergen environment and/or food †¢ Over the counter medication (histamines) †¢ Prescription drugs & nasal drops, †¢ Allergy shots †¢ Allergy Drops †¢ Immunotherapy †¢ Alternate TherapiesOnce a person knows the substance that causes allergy, the best treatment is to avoid that substance. However avoiding allergen is not always possible as it is not possible to breathe. Food allergens can be easily avoided [When Should I Get Medical Treatment for Allergy, 2006] . In a very large number of case s of mild allergy over the counter medication is all one needs to relieve the symptoms. It is important to consult a doctor for over the counter medicine too, as some of these medicines if used excessively can cause serious side effects. Most of the histamines cause drowsiness.Antihistamines and decongestants relieve the symptoms of most allergy sufferers. Again, a physician’s advice should be sought. Many new antihistamines relieve the symptoms of allergy without causing drowsiness. In sinus congestion, nasal sprays available on prescription provide quick relief from symptoms of allergy. Allergy shots prevent the allergen from being recognized as a foreign body. This treatment is becoming very popular. Sublingual drops also known as sublingual Immunotherapy (SLIT) is an alternate to allergy shots and has the same principle of desensitization.Oral application of SLIT is also considered convenient by the patients. Those interested in alternative medicine often recommend severa l alternate therapies. Dietary supplements are said to increase health of immune system and prevent allergies. The other alternative medicines are beyond the scope of this paper. [Allergies, 2006a] provides several references to alternative treatment websites. Anaphylaxis must be considered a medical emergency and immediate medical help must be sought as it can cause low blood pressure, hyper-constriction, coma and even death.Prevention Methods The best prevention is to avoid the allergen responsible for causing the allergy. Cross the counter medicine approved by a patients physician may also be used before coming into contact with allergens. In view of the number of sufferers, various equipments such as vacuum cleaners, humidifiers, beddings and air purifiers are available in the market to control domestic allergens. A physician may be able to advice about prevention methods about other specific allergies. Bibliography 1.Allergies, (2006a), Alternative Allergy Treatment Options, [O nline], retrieved from Internet on 10 January 2007, http://allergies. about. com/od/alternatives/Alternative_Allergy_Treatment_Options. htm 2. Allergies, (2006b), [Online], retrieved from Internet on 10 January 2007, http://www. med-help. net/Allergies. html 3. Allergy, (2006), What is Allergy, [Online], retrieved from Internet on 10 January 2007, http://www. setel. com/~allergy/Products/allergy 4. Bornehag C, Sundell J, Weschler C, Sigsgaard T, Lundgren B, Hasselgren M, Hagerhed-Engman L (2004).â€Å"The association between asthma and allergic symptoms in children and phthalates in house dust: a nested case-control study. † Environ Health Perspective 112 (14): 1393-7. 5. Guyton, AC, and Hall, JE, (2006), Textbook of Medical Physiology-11th Edition, Published by Elsevier, Pa. , ISBN 13-81-8147-920-3 6. LabSpec, Allergy Diagnostic Tests, (2006) [Online], retrieved from Internet on 10 January 2007, http://www. labspec. co. za/diag. htm 7. Levinson, W. , (2004), Medical Microbio logy & Immunology, 8th Edition, McGraw Hill Companies, ISBN 0-07-143199-3 8. Leznoff. A., (1999), Provocative challenges in patients with multiple chemical sensitivity, J Allergy Clin Immunol 1997 Apr; 99 (4):438-42 9. NIH- National Institute of Health/ National Institute of Allergy and Infectious Diseases (NIAID), (2000), International Team Accelerates Investigation of Immune-Related Genes, [Online], retrieved from Internet on 10 January 2007, http://www3. niaid. nih. gov/news/newsreleases/2000/ihwg. htm 10. When Should I Get Medical Treatment for Allergies? , (2006) [Online], retrieved from Internet on 10 January 2007, http://health. howstuffworks. com/allergy-treatments-ga1. htm

What Redshift Reveals About an Object

When stargazers look up at the night sky, they see light. Its an essential part of the universe that has traveled across great distances. That light, formally called electromagnetic radiation, contains a treasury of information about the object it came from, ranging from its temperature to its motions. Astronomers study light in a technique called spectroscopy. It allows them to dissect it down to its wavelengths to create whats called a spectrum. Among other things, they can tell if an object is moving away from us. They use a property called a redshift to describe the motion of an objects moving away from each other in space. Redshift occurs when an object emitting electromagnetic radiation recedes from an observer. The light detected appears redder than it should be because it is shifted toward the red end of the spectrum. Redshift is not something anyone can see. Its an effect that astronomers measure in light by studying its wavelengths.   How Redshift Works An object (usually called the source) emits or absorbs electromagnetic radiation of a specific wavelength or set of wavelengths. Most stars give off a wide range of light, from visible to infrared, ultraviolet, x-ray, and so on. As the source moves away from the observer, the wavelength appears to stretch out or increase. Each peak is emitted farther away from the previous peak as the object gets recedes. Similarly, while the wavelength increases (gets redder) the frequency, and therefore the energy, decreases. The faster the object recedes, the greater its redshift. This phenomenon is due to the doppler effect. People on Earth are familiar with Doppler shift in pretty practical ways. For example, some of the most common applications of the doppler effect (both redshift and blueshift) are police radar guns. They bounce signals off of a vehicle and the amount of redshift or blueshift tells an officer how fast its going. Doppler weather radar tells forecasters how fast a storm system is moving. The use of Doppler techniques in astronomy follows the same principles, but instead of ticketing galaxies, astronomers use it to learn about their motions.   The way astronomers determine redshift (and blueshift) is to use an instrument called a spectrograph (or spectrometer) to look at the light emitted by an object. Tiny differences in the spectral lines show a shift toward the red (for redshift) or the blue (for blueshift). If the differences show a redshift, it means the object is receding away. If theyre blue, then the object is approaching. The Expansion of the Universe In the early 1900s, astronomers thought that the entire universe was encased inside our own  galaxy, the Milky Way. However, measurements made of other galaxies, which were thought to be simply nebulae inside our own, showed they were really  outside of the Milky Way. This discovery was made by astronomer Edwin P. Hubble, based on measurements of variable stars by another astronomer named  Henrietta Leavitt.   Furthermore, redshifts (and in some cases blueshifts) were measured for these galaxies, as well as their distances. Hubble  made the startling discovery that the farther away a galaxy is, the greater its redshift appears to us. This correlation is now known as Hubbles Law. It helps astronomers define the expansion of the universe.   It also shows that the farther away objects are from us, the faster they are receding. (This is true in the broad sense, there are local galaxies, for instance, that are moving towards us due to the motion of our Local Group.)   For the most part, objects in the universe are receding away from each other and that motion can be measured by analyzing their redshifts. Other Uses of Redshift in Astronomy Astronomers can use redshift to determine the motion of the Milky Way. They do that by measuring the Doppler shift of objects in our galaxy. That information reveals how other stars and nebulae are moving in relation to Earth. They can also measure the motion of very distant galaxies — called high redshift galaxies.   This is a rapidly growing field of astronomy. It focuses not just on galaxies, but also on other other objects, such as the sources of  gamma-ray bursts. These objects have a very high redshift, which means they are moving away from us at tremendously high velocities. Astronomers assign the letter z to redshift. That explains why sometimes a story will come out that says a galaxy has a redshift of z1 or something like that. The earliest epochs of the universe lie at a z of about 100.   So, redshift also gives astronomers a way to understand how far away things are in addition to how fast they are moving.   The study of distant objects also gives astronomers a snapshot of the state of the universe some 13.7 billion years ago. Thats when cosmic history began with the Big Bang. The universe not only appears to be expanding since that time, but its expansion is also accelerating. The source of this effect is dark energy,  a not-well-understood part of the universe. Astronomers using redshift to measure cosmological (large) distances​ find that the acceleration has not always been the same throughout cosmic history. The reason for that change is still not known and this effect of dark energy remains an intriguing area of study in cosmology (the study of the origin and evolution of the universe.) Edited by Carolyn Collins Petersen.