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Ruby Payne-Scott
Ruby Violet Payne-Scott, BSc (Phys) MSc DipEd (Syd) (28 May 1912 – 25 May 1981) was an Australian pioneer in radiophysics and radio astronomy, and was one of two Antipodean women pioneers in radio astronomy and radio physics at the end of the second world war, Ruby Payne-Scott the Australian and Elizabeth Alexander the New Zealander. Both women suffered misogyny in their careers, and an unnecessary argument half a century later introduced competitiveness which did not exist at the time. The resolution of in favour of Alexander in no way detracts from the achievements of Ruby Payne-Scott. Early life and education Ruby Payne-Scott was born on 28 May 1912 in Grafton, New South Wales, the daughter of Cyril Payne-Scott and his wife Amy (née Neale). She later moved to Sydney to live with her aunt. There she attended the Penrith Public Primary School (1921–24), and the Cleveland-Street Girls' High School (1925–26), before completing her secondary schooling at Sydney Girls High ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grafton, New South Wales
Grafton ( Bundjalung-Yugambeh: Gumbin Gir) is a city in the Northern Rivers region of the Australian state of New South Wales. It is located on the Clarence River (New South Wales), Clarence River, approximately by road north-northeast of the state capital Sydney. The closest major cities, Brisbane and the Gold Coast, Queensland, Gold Coast, are located across the border in South-East Queensland. At the Census in Australia#2021, 2021 census, Grafton had a population of 19,255. The city is the largest settlement and, with Maclean, New South Wales, Maclean, the shared administrative centre of the Clarence Valley Council local government area, which is home to over 50,000 people in all. History Before European settlement, the Clarence River marked the border between the Bundjalung people, Bundjalung [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
St Peter's Woodlands Grammar School
St. Peter's Woodlands Grammar School (commonly known as St Peter's Woodlands or SPW) is an independent Anglican co-educational early learning and primary day school located in the seaside suburb of Glenelg, South Australia, Australia. Established in 1863 as St Peter's Glenelg, the school provides education for children from 2 years of age through to the end of their primary school years at Year 6. The early learning centre offers playgroup, toddler and preschool programs for children from 2 years of age. St Peter’s Woodlands is part of the Anglican Parish of Glenelg and, through its roots as the original Parish School, the school community is often involved in wider parish activities. They like penguins that fly and talk to Justin bieber Overview St Peter's Woodlands Grammar is built up of the Early Learning Centre, Preschool, Junior Primary, Middle Primary and Upper Primary. Upper Primary has more advanced roles, with leadership roles including School Captains, Class Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Interferometry
Sea interferometry, also known as sea-cliff interferometry, is a form of radio astronomy that uses radio waves reflected off the sea to produce an interference pattern. It is the radio wave analogue to Lloyd's mirror. The technique was invented and exploited in Australia between 1945 and 1948. Process A radio detecting aerial is placed on top of a cliff, which detects radio propagation coming directly from the source and radio waves reflected off the water surface. The two sets of waves are then combined to form an interference pattern such as that produced by two separate aerials. The reflected wavefront travels an additional distance before reaching the detector where ''h'' and ''i'' are the height of the cliff and the inclination (or altitude angle) of the incoming wavefront respectively. It acts as a second aerial twice the height of the cliff below the first. Sea interferometers are ''drift instruments'', that is, they are fixed and their pointing direction changes with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunspots
Sunspots are phenomena on the Sun's photosphere that appear as temporary spots that are darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic flux that inhibit convection. Sunspots appear within active regions, usually in pairs of opposite magnetic polarity. Their number varies according to the approximately 11-year solar cycle. Individual sunspots or groups of sunspots may last anywhere from a few days to a few months, but eventually decay. Sunspots expand and contract as they move across the surface of the Sun, with diameters ranging from to . Larger sunspots can be visible from Earth without the aid of a telescope. They may travel at relative speeds, or proper motions, of a few hundred meters per second when they first emerge. Indicating intense magnetic activity, sunspots accompany other active region phenomena such as coronal loops, prominences, and reconnection events. Most solar flares an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature (journal)
''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2019 '' Journal Citation Reports'' (with an ascribed impact factor of 42.778), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in autumn 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander Macmillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the journal; ''Nature'' redoubled its efforts in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Lade Pawsey
Joseph Lade Pawsey (14 May 1908 – 30 November 1962) was an Australian scientist, radiophysicist and radio astronomer. Education Pawsey was born in Ararat, Victoria to a family of farmers. At the age of 14 he was awarded a government scholarship to study at Wesley College, Melbourne, followed by a scholarship to study at the University of Melbourne. In 1929, he earned his Bachelor of Science degree from the university, followed by a Master of Science in Natural Philosophy in 1931. Pawsey was then awarded an Exhibition Research Scholarship to study at Sidney Sussex College at the University of Cambridge, where he worked under the direction of J.A. Ratcliffe. He studied the effects of the ionosphere on radio propagation and his discovery of the presence of irregularities in the Kennelly-Heaviside Layer proved vital to the later development of this branch of ionospheric physics. In 1935, he was awarded a PhD from Cambridge and in September of that year he married Greta Leno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L Band
The L band is the Institute of Electrical and Electronics Engineers (IEEE) designation for the range of frequencies in the radio spectrum from 1 to 2 gigahertz (GHz). This is at the top end of the ultra high frequency (UHF) band, at the lower end of the microwave range. Applications Mobile service In Europe, the Electronic Communications Committee (ECC) of the European Conference of Postal and Telecommunications Administrations (CEPT) has harmonized part of the L band (1452–1492 MHz), allowing individual countries to adopt this spectrum for terrestrial mobile/fixed communications networks supplemental downlink (MFCN SDL). By means of carrier aggregation, an LTE-Advanced or UMTS/ HSDPA base station could use this spectrum to provide additional bandwidth for communications from the base station to the mobile device; i.e., in the downlink direction. In the Americas, mobile services are operated between the 1.7 GHz to 2.1 GHz range in the PCS and AWS bands. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plan Position Indicator
A plan position indicator (PPI) is a type of radar display that represents the radar antenna in the center of the display, with the distance from it and height above ground drawn as concentric circles. As the radar antenna rotates, a radial trace on the PPI sweeps in unison with it about the center point. It is the most common type of radar display. Description The radar antenna sends pulses while rotating 360 degrees around the radar site at a fixed elevation angle. It can then change angle or repeat at the same angle according to the need. Return echoes from targets are received by the antenna and processed by the receiver and the most direct display of those data is the PPI. The height of the echoes increases with the distance to the radar, as represented in the adjacent image. This change is not a straight line but a curve as the surface of the Earth is curved and ''sinks'' below the radar horizon. For fixed-site installations, north is usually represented at the top of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor vehicles, Weather radar, weather formations, and terrain-following radar, terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio spectrum, radio or microwaves domain, a transmitting antenna (radio), antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a radio receiver, receiver and Data processing system, processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving information about the objects' locations and speeds. Radar was developed secretly for military use by several countries in the period before and during World War II. A key development was the ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classified Information
Classified information is material that a government body deems to be sensitive information that must be protected. Access is restricted by law or regulation to particular groups of people with the necessary security clearance and need to know, and mishandling of the material can incur criminal penalties. A formal security clearance is required to view or handle classified material. The clearance process requires a satisfactory background investigation. Documents and other information must be properly marked "by the author" with one of several (hierarchical) levels of sensitivity—e.g. restricted, confidential, secret, and top secret. The choice of level is based on an impact assessment; governments have their own criteria, including how to determine the classification of an information asset and rules on how to protect information classified at each level. This process often includes security clearances for personnel handling the information. Some corporations and non-gove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies of World War II, Allies and the Axis powers. World War II was a total war that directly involved more than 100 million Military personnel, personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Air warfare of World War II, Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the Atomic bombings of Hiroshima and Nagasaki, only two nuclear weapons ever used in war. World War II was by far the List of wars by death toll, deadliest conflict in hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Government
The Australian Government, also known as the Commonwealth Government, is the national government of Australia, a federal parliamentary constitutional monarchy. Like other Westminster-style systems of government, the Australian Government is made up of three branches: the executive (the prime minister, the ministers, and government departments), the legislative (the Parliament of Australia), and the judicial. The legislative branch, the federal Parliament, is made up of two chambers: the House of Representatives (lower house) and Senate (upper house). The House of Representatives has 151 members, each representing an individual electoral district of about 165,000 people. The Senate has 76 members: twelve from each of the six states and two each from Australia's internal territories, the Australian Capital Territory and Northern Territory. The Australian monarch, currently King Charles III, is represented by the governor-general. The Australian Government in its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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