How Radio Waves Help Us Understand the Universe

Humans perceive the universe using visible light that we can see with our eyes. Yet, theres more to the cosmos than what we see using the visible light that streams from stars, planets, nebulae, and galaxies. These objects and events in the universe also give off other forms of radiation, including radio emissions. Those natural signals fill in an important part of the cosmic of how and why objects in the universe behave as they do. Tech Talk: Radio Waves in Astronomy Radio waves are electromagnetic waves (light), but we cant see them. They have wavelengths between 1 millimeter (one-thousandth of a meter) and 100 kilometers (one kilometer is equal to one thousand meters). In terms of frequency, this is equivalent to 300 Gigahertz (one Gigahertz is equal to one billion Hertz) and 3 kilohertz. A Hertz (abbreviated as Hz) is a commonly used unit of frequency measurement. One Hertz is equal to one cycle of frequency. So, a 1-Hz signal is one cycle per second. Most cosmic objects emit signals at hundreds to billions of cycles per second. People often confuse radio emissions with something that people can hear. Thats largely because we use radios for communication and entertainment. But, humans do not hear radio frequencies from cosmic objects. Our ears can sense frequencies from 20 Hz to 16,000 Hz (16 KHz). Most cosmic objects emit at Megahertz frequencies, which is much higher than the ear hears. This is why radio astronomy (along with x-ray, ultraviolet, and infrared) is often thought to reveal an invisible universe that we can neither see nor hear. Sources of Radio Waves in the Universe Radio waves usually are emitted by energetic objects and activities in the universe. The   Sun is the closest source of radio emissions beyond Earth. Jupiter also emits radio waves, as do events occurring at Saturn. One of the most powerful sources of radio emission outside of the solar system, and beyond the Milky Way  galaxy, comes from active galaxies (AGN). These dynamic objects are powered by supermassive black holes at their cores. Additionally, these black hole engines will create massive jets of material that glow brightly with radio emissions. These can often outshine the entire galaxy in radio frequencies. Pulsars, or rotating neutron stars, are also strong sources of radio waves. These strong, compact objects are created when massive stars die as  supernovae. Theyre  second only to black holes in terms of ultimate density. With powerful magnetic fields and fast rotation rates, these objects emit a broad spectrum of  radiation, and they are particularly bright in radio. Like supermassive black holes, powerful radio jets are created, emanating from the magnetic poles or the spinning neutron star. Many pulsars are referred to as radio pulsars because of their strong radio emission. In fact, data from the  Fermi Gamma-ray Space Telescope  showed evidence of a new breed of pulsars that appears strongest in gamma-rays instead of the more common radio. The process of their creation remains the same, but their emissions tell us more about the energy involved in each type of object.   Supernova remnants themselves can be particularly strong emitters of radio waves. The Crab Nebula is famous for its radio signals that alerted astronomer Jocelyn Bell to its existence.   Radio Astronomy Radio astronomy is the study of objects and processes in space that emit radio frequencies. Every source detected to date is a naturally occurring one. The emissions are picked up here on Earth by  radio telescopes. These are large instruments, as it is necessary for the detector area to be larger than the detectable wavelengths. Since radio waves can be larger than a meter (sometimes much larger), the scopes are typically in excess of several meters (sometimes 30 feet across or more). Some wavelengths can be as large as a mountain, and so astronomers have built extended arrays of radio telescopes.   The larger the collection area is, compared to the wave size, the better the angular resolution a radio telescope has. (Angular resolution is a measure of how close two small objects can be before they are indistinguishable.) Radio Interferometry Since radio waves can have very long wavelengths, standard radio telescopes need to be very large in order to obtain any sort of precision. But since building stadium size radio telescopes can be cost prohibitive (especially if you want them to have any steering capability at all), another technique is needed to achieve the desired results. Developed in the mid-1940s, radio interferometry aims to achieve the kind of angular resolution that would come from incredibly large dishes without the expense. Astronomers achieve this  by using multiple detectors in parallel with each other. Each one studies the same object at the same time as the others. Working together, these telescopes effectively act like one giant telescope the size of the whole group of detectors together. For example, the Very Large Baseline Array has detectors 8,000 miles apart. Ideally, an array of many radio telescopes at different separation distances would work together to optimize the effective size of the collection area as well improve the resolution of the instrument. With the creation of advanced communication and timing technologies, it has become possible to use telescopes that exist at great distances from each other (from various points around the globe and even in orbit around  the Earth). Known as Very Long Baseline Interferometry (VLBI), this technique significantly improves the capabilities of individual radio telescopes and allows researchers to probe some of the most dynamic objects in the  universe. Radios Relationship to Microwave Radiation The radio wave band also overlaps with the microwave band (1 millimeter to 1 meter). In fact, what is commonly called  radio astronomy, is really microwave astronomy, although some radio instruments do detect wavelengths much beyond 1 meter. This is a source of confusion as some publications will list the microwave band and radio bands separately, while others will simply use the term radio to include both the classical radio band and the microwave band. Edited and updated by Carolyn Collins Petersen.

The Struggle Of Women By The Sherlock Holmes Stories By...

In crime fiction, many themes are encountered in crime stories, enabling the reader to reflect on the cultural and moral values of the society. These stories discuss various topics such as race, ethnicity, sexism, and femininity. In the Sherlock Holmes stories by Sir Arthur Conan Doyle, the independence of women is shown as a conflict in society that must be solved and controlled by men. This may be demonstrated by the poor representation of single women present in the Sherlock Holmes stories, such as Mary Morstan and Irene Adler who are considered as a problem in this society, because they do not have the presence of a male figure guiding them in their everyday lives. In the stories, the issues caused by these women are redundantly resolved by marrying a man. This implies an unacceptable prejudice towards the female gender. Firstly, in the stories, single women who are alone appear to be problematic due to the lack of men in their everyday lives. Mary Morstan is isolated, and must be saved by men, whereas Irene Adler is presented as being a scandalous woman who must be restrained. As Mary Morstan first approaches Holmes and Watson to state her case, she explains that her mother has deceased, her father has disappeared, and that she does not have any other family member close by to be there for her, therefore, she is alone. She says: â€Å"My father was an Indian regiment, [...] My mother was dead, and I had no relative in England.† (Conan Doyle,Show MoreRelatedThe Character of Sherlock Holmes in Sir Arthur by Conan Doyle1742 Words   |  7 PagesThe Character of Sherlock Holmes in Sir Arthur by Conan Doyle Sir Arthur Conan Doyle, the renowned author who gave birth to the extraordinary crime detective tales of Sherlock Holmes. Conan Doyle was born on May 22, 1859, in Edinburgh and educated at Stonyhurst College and the University of Edinburgh. From 1882 to 1890 he practiced medicine in Southsea, England. A Study in Scarlet, the first of 60 stories featuring Sherlock Holmes, appeared in 1887. The characterizationRead MoreThe Stories Of Sir Arthur Conan Doyle937 Words   |  4 PagesSir Arthur Conan Doyle is a 19th century author who is known by his stories of Sherlock Holmes. Sherlock Holmes is a crime series based in the Victorian era when â€Å"feminists in this period were calling for women and children to have equal protection under the law† (Miller 55). He is consider one of most known iconic British characters created who solves mysteries with visual detection. One thing is clear author Conan Doyle portrays women as a weakness in Holmes’s visual approach, â€Å"his extraordinaryRead MoreThe Veiled Lodger by Sir Arthur Conan Doyle and The Lamb To The Slaughter by Roald Dahl1436 Words   |  6 PagesIn the stories The Veiled Lodger by Sir Arthur Conan Doyle, and The Lamb To The Slaughter by Roald Dahl, both women murder their husbands. Who do you have the most sympathy for, and why? In the stories The Veiled Lodger by Sir Arthur Conan Doyle, and The Lamb To The Slaughter by Roald Dahl, both women murder their husbands. Who do you have the most sympathy for, and why? The adventure of the veiled lodger is an epic tale of treachery, murder, and deceit. Written in VictorianRead MoreComparing Sherlock Holmes the Speckled Band and Roald Dahls Lamb to the Slaughter2524 Words   |  11 PagesComparing the two stories ‘The Adventures of the Speckled Band’ and ‘The Lamb to the Slaughter’ Within this essay I will be comparing and contrasting the two detective stories ‘The Adventures of the Speckled Band’ and ‘The Lamb to the Slaughter’, referring to the structure, language and characterisation. ‘The speckled band’ was written in 1892 by Sir Arthur Doyle, he was qualified as a doctor which gave him a medical perspective for all his stories. ‘The lamb to the slaughter’ was written in 1952Read MoreSusan Glaspell’s One-Act Play, Trifles: Men Vs Women1190 Words   |  5 Pagesthe women for spending time â€Å"worrying over trifles† (Glaspell 918) rather than the case. Ironically, the women’s subjective notions about the case lead to a better understanding of the circumstances than the men’s cold and objective view of the facts of the case. In â€Å"Trifles† the conflict between the sexes can be based on one very important question, how are the perceptions of the men and the women diffe rent and from where does their internal bias arise? Upon closer inspection of the story, weRead MoreVictorian Novel9605 Words   |  39 Pagesthat its new type emerged- sensational fiction. Written as more entertaining form, it appealed to the middle-class women, especially housewives. They were interested in the tales of bigamy, double identity, violence, set in the realities close to what they were familiar with. What is more, during that time the nation had to face two challenges of social quality. The position of the women in society and their rights to own property within marriage, and the problem of illiteracy- poorer classes were not

Antecedents and Consequences of Ethical Leadership †Free Samples

Question: Discuss about the Antecedents and Consequences of Ethical Leadership. Answer: Introduction: The essay deals with the analysis of aspects of change that has been observed in a group. Leadership is the ability of translating visions into realities. Devoid of proper governance and efficient leadership at every level in civil, public and private organizations, it is debatably nearly impossible to sustain and achieve efficient administration, to accomplish goals, to maintain the quality as well as deliver first class services. The growing requirements and complexities that arise from the continuous changes in the society, in addition to the continuous drive for higher productivity, call for ethical and effective leadership (Auerbach, 2012). Proper governance with ethical and effective leadership is the vital requirements for an organization to do well in the twenty-first century. Quality leadership in the educational field is essential for an all-round success of a school system or an individual school. Dwight D. Eisenhower, the thirty-fourth President of United States, had stated in his definition of leadership that it is an art of getting something done by somebody else. Leadership is witnessed at not only the work place, but almost everywhere. At all circumstances, the leader initiates or takes a step forward for taking charge of the situations. It can be at the workplace, educational institution, or any other place. No person is a leader from the birth. A person becomes a leader as they have the sincerity and credibility, as a result other individuals would be inclined to obey or follow them (Flores et al., 2012). As per my observation, the leaders possessed exemplary leadership skills and qualities such as honesty, confidence, commitment, discipline, positive attitude and creativity. The body language of the leaders was appropriate and they were active listeners. The group members were able to participate actively in the group sessions and share their views. Proper planning was done by the leaders, which helped in proper management of the group activities. The leaders regularly invited the group members to share their views and opinions on the happenings over the weeks. The leaders encouraged the participation of the group members in the group activities by properly interacting with them in a two way communication process. However, a few members took active participation in the group meetings while the others remained reluctant. The major issue, which aroused was the lack of confidence among a few members. Due to lack of confidence, a few group members could not openly express their views and could not freely participate in the group activities. Throughout the session, I have observed that the leaders were friendly in nature and encouraged all the group members to participate in the group activities. They were successful in paying equal attention to all the members. In order to make the activities interesting, the leaders often asked questions to the group members and tried to raise the level of confidence of the group members who lacked the courage to put forward their views and suggestions. I observed the leaders to be emphatic and enforce a cross- cultural leadership style. Since the group members belonged to different cultures and backgrounds, the implementation of cross- cultural leadership proved to be fruitful for the group activities and restored peace and harmony among the group members. Cross- cultural leadership style ensured that there is equality among the members and no discrimination on any grounds. This enables the group members to form healthy personal relations with the leaders (Galegher, Kraut Egido, 2014 ). An indispensable quality that is important for being an efficient leader, is to have a balanced attitude and have different perspectives. Possessing these qualities gives an ability to view the world from various angles. I, as a leader assuming to be equipped with these qualities, opine that, the mode by which I perceive the world is definitely not the only mode of perceiving. Rather, I believe in the principle thatthe world is viewed by various ways by different people. By the conception of perspective, I believe that, there is a probability to modify my views to give new insight for my actions. This quality calls for immense intellectualities as well as philosophical modesty from members of a certain organization (Dugan, Kodama Gebhardt, 2012). The factor of body language determination has been an important part in the observation process. It comprises of gesture, facial expression and others. Body language makes a major impact as a speaker. Some members make gestures by nodding heads, which may either imply a yes or a no. However, it varies from person to person. It has been evident that meetings are a process followed in any workplace. The reason can be sharing of thoughts. There are pseudo listeners who act or pretend to listen. However, active listening has really been on the focus, as it is the process of listening in a full attentive manner. This process has been aggravated by globalization. The seating arrangement has also been an area of focus in my observation, as it can influence the whole interaction or meeting among people. However, it often happens by chance, and not intentionally. It has been assumed that seating arrangements should be done by providing justice to every member. The leaders were placed at the centre, able to communicate and obverse the other members. The strategy of shared leadership was observed to be working in the educative group. Shared leadership models of governance mean the leaders seek out other persons in the school premises to build a partnership, hit the strengths of others, and progress the vision forward jointly. The leaders acted and believed in traditions that call for invitations and encouraged a common purpose appreciate that intensified relationship that was developed by both informal and formal interaction and was elementary to motivate every member to proceed in a similar direction. Planning in a group helps in achieving a common goal. Similarly, I have observed that the leaders ensured that there is an alternative plan in case the primary plan does not work. As one of the various leadership aspects, implementation of a fruitful change management strategy is an important part of any fruitful leadership strategy of the team. Organizational change has been a constant trait of contemporary organizations and the reliance upon program delivery and successful projects has not been higher. It does not depend on the shortage of money that is generating a large number of strategic initiative mishaps (Mendenhall, 2012). The most important causes are often related to inadequate communications, across the organization. Effective leaders in the school are the key to a large scale and sustainable reform of education. Leaders have a deep and more lasting impact on organization and provides more comprehensive headship if the focus spreads beyond sustaining high standards. Cultural Change leaders display blatant enthusiasm, hope and energy. Moreover, few indispensable components characterizes the leaders in the knowledge society, such as moral purpose, understanding of the process of change, the ability to develop relationship, knowledge sharing and creation, and rationality (Holt Marques, 2012). Moral purpose is the societal responsibility to the environment and other persons. leaders in school with a moral purpose intend to make some differences in the lives of the students. They have been concerned regarding bridging the gap between the high performers and lower performers in schools and raising the achievements of the students (Bogotch, 2014). The objective is not just to innovate, but Innovating in a selective manner with rationality is considered better. Possessing the best idea is not sufficient. The leaders helped other persons to find and assess collective meanings and commitments to new means. The leaders did not avoid the expected early difficulty of trying some new thing. It was known to them, for instance, that regardless of how much they arrange or plan for the changes, the first few months after implementing will be rough (Wagner et al., 2012). Resistance is to be redefined. Successful leaders are generally not concerned when naysayers cause an argument. Sometimes the doubters have significant points to be taken into consideration. Leaders seek for means for addressing those concerns. Reculturing has been the name of the game, which says that a culture of the school influences the thought process of the people, their feelings, and actions. Being competent to shape and understand the culture is a key to the success of schools in promoting learning of the students and staffs (Northouse, 2015). Creation and sharing of knowledge is fundamental to effective leaderships. Information, facts or data, of which we have an overabundance, simply becomes knowledge by asocialprocess. Therefore, professional learning communities and relationships are necessary. Organizations must promote knowledge seeking as well as knowledge giving. Student Success Skills is a program designed for helping the students to develop the academic, self management and social skills that are required to be successful in schools. The counselors in school are encouraged for setting themselves up for the success in presentation of outcomes by implementation of the interventions as anticipated and keeping a track of the attendance of the student in a group session (Mayer et al., 2012). Good Governance and efficient leadership are considered two sides of one coin. The two have several mutual elements. Good Governance may not be envisaged by us in totality without an efficient leadership. In reality, we may not achieve good governance in totality for psychological, sociological and cultural impacts as well as differences. Leaders are expected to walk their talk; that is, the leaders are expected to practically do what has beensaid by their mouth. Promptness for accepting the change is an additional essential constituent to ensure good governance; in order that the present leaders as well as the emerging leaders in future ought to be prepared for accepting the change and proceed accordingly. References Auerbach, S. (Ed.). (2012).School leadership for authentic family and community partnerships: Research perspectives for transforming practice. Routledge. Bogotch, I. (2014). Educational theory: The specific case of social justice as an educational leadership construct. InInternational handbook of educational leadership and social (in) justice(pp. 51-65). Springer Netherlands. Dugan, J. P., Kodama, C. M., Gebhardt, M. C. (2012). Race and leadership development among college students: The additive value of collective racial esteem.Journal of Diversity in Higher Education,5(3), 174. Flores, K. L., Matkin, G. S., Burbach, M. E., Quinn, C. E., Harding, H. (2012). Deficient critical thinking skills among college graduates: Implications for leadership.Educational Philosophy and Theory,44(2), 212-230. Galegher, J., Kraut, R. E., Egido, C. (2014).Intellectual teamwork: Social and technological foundations of cooperative work. Psychology Press. Holt, S., Marques, J. (2012). Empathy in leadership: Appropriate or misplaced? An empirical study on a topic that is asking for attention.Journal of business ethics,105(1), 95-105. Mayer, D. M., Aquino, K., Greenbaum, R. L., Kuenzi, M. (2012). Who displays ethical leadership, and why does it matter? An examination of antecedents and consequences of ethical leadership.Academy of Management Journal,55(1), 151-171. Mendenhall, M. E. (Ed.). (2012).Global leadership: Research, practice, and development. Routledge. Northouse, P. G. (2015).Leadership: Theory and practice. Sage publications. Wagner, T., Kegan, R., Lahey, L. L., Lemons, R. W., Garnier, J., Helsing, D., ... Rasmussen, H. T. (2012).Change leadership: A practical guide to transforming our schools. John Wiley Sons.

Lamb To The Slaughter By Dahl Essays - Lamb To The Slaughter, Lamb

Lamb To The Slaughter By Dahl Characterization, a method that an author chooses to develop his/her character, is a very important element in a story. In "Lamb to the Slaughter," Roald Dahl, effectively develops the protagonist both directly and indirectly; however, the use of indirect characterization is more dominant because it reveals her actions and how she deals with her conflict, her words, and creating a dynamic character with her words, and her personality. First, she seems like a typical house-wife longing for her husband to return, but something is odd about this particular day; "There was a slow smiling air about her, and about everything she did...was curiously tranquil...the eyes, with their new placid look, seemed larger, and darker than before" (108). It was almost as if she is expecting something unusual to happen, and that she is preparing for that specific moment. In addition, her actions change from being a wife-pleasing-husband, to a self-conscious woman that knew all of a sudden, exactly what to do, as if she had been prepared for months. Also, in the beginning of the story she is described as a inoffensive, harmless person, but immediately after her husband reveals his burden, she becomes unstable and almost naturally she hits her husband. She "...simply walked up behind him and without any pause she swung the big frozen leg of lamb...and brought it down as hard as she could..." (111). And as strange as it looks, she goes somewhat through a metamorphoses, from being a content house-wife, to a maniac, possessed woman, to the point of killing her husband. Second, she reveals through her words, her duplicity and deceitfulness by exterminating all the evidence left. When the police arrived she trying to hide evidence, asks for her husband's whiskey, "?Jack...would you mind giving me a drink?'...'You mean this whiskey?'...'Yes, please'...'Why don't you eat up that lamb that is in the oven?'..." (115,116), and the reader realizes that she tries to convince others with her deceitful lies, and with a concrete set of credible words, she gets away easily; "She tried a smile. It came out so peculiar...The voice sounded so peculiar too...She rehearsed it several times more..." (112). Mrs. Maloney, had thought about it even before the incident happened, for she tries to look as normal as possible, by acting it out her daily routine. Finally, her personality creates in her a dynamic characterization, and as the reader observes it when she is talking to the shopkeeper, by saying something very odd: "'I got a nice leg of lamb from the freezer...I don't much like cooking it frozen...but I'm taking a chance on it this time. You think it'll be alltight?" (112). What she was really referring, was what she had done just minutes ago. But when she said , at the end, to him if "it'll be allright?" she revealed a weak, fragile nature as if she had been pulled out of a protective coat all of a sudden and left naked, for she is described by the narrator as a loving and faithful wife, who is willing to do anything for her husband. Moreover, at the end when she offers the leg of lamb to the officers, she does another extraordinary act; "And in the other room, Mary Maloney began to giggle" (116). And by doing so, she was declaring that she was indeed independent, and was mature enough to make her own decisions based on what she thought was the best, not others. Roald Dahl, developed the protagonist successfully in "Lamb to the Slaughter," through a way that is important in this short story. Where indirect characterization is the most predominant in the protagonist's actions, words, and how the author creates a convincing dynamic character, which reflects it in the body itself.