Edward Victor Appleton
Encyclopedia
Sir Edward Victor Appleton, GBE
, KCB, FRS (6 September 1892 – 21 April 1965) was an English
physicist
.
, West Yorkshire
and educated at Hanson Grammar School
. At the age of 18 he won a scholarship to St John's College, Cambridge
. He graduated with a first class degree in Natural Sciences.
During the First World War he joined the West Riding Regiment
, and later transferred to the Royal Engineers
. After returning from active service in World War I
, Appleton became assistant demonstrator in experimental physics at the Cavendish Laboratory
in 1920. He was professor of physics at King's College London
(1924–36) and professor of natural philosophy at Cambridge University
(1936–39). From 1939 to 1949 he was secretary of the Department of Scientific and Industrial Research
. Knighted in 1941, he received the 1947 Nobel Prize in Physics
for his contributions to the knowledge of the ionosphere
, which led to the development of radar
.
From 1949 until his death in 1965, he was Principal and Vice-Chancellor of the University of Edinburgh
. In 1956, the BBC invited him to deliver the annual Reith Lectures. Across a series of six radio broadcasts, titled Science and the Nation, Appleton explored the many facets of scientific activity in Britain at the time.
The existence of a reflecting atmospheric layer was not in itself a completely new idea. Balfour Stewart had suggested the idea in the late nineteenth century to explain rhythmic changes in the earth’s magnetic field. More recently, in 1902, Oliver Heaviside
and A.E. Kennelly had suggested such a hypothesis may explain the success Marconi had in transmitting his signals across the Atlantic. Calculations had shown that natural bending of the radio waves was not sufficient to stop them from simply “shooting off” into empty space before they reached the receiver.
Appleton thought the best place to look for evidence of the ionosphere was in the variations he believed it was causing around sunset in radio signal receptions. It was sensible to suggest these variations were due to the interference of two waves but an extra step to show that the second wave causing the interference (the first being the ground wave) was coming down from the ionosphere. The experiment he designed had two methods to show ionospheric influence and both allowed the height of the lower boundary of reflection (thus the lower boundary of the reflecting layer) to be determined. The first method was called frequency modulation and the second was to calculate the angle of arrival of the reflected signal at the receiving aerial.
The frequency modulation method exploits the fact that there is a path difference between the ground wave and the reflected wave, meaning they travel different distances from sender to receiver.
Let the distance AC travelled by the ground wave be h and the distance ABC travelled by the reflected wave h’. The path difference is:
The wavelength of the transmitted signal is λ . The number of wavelengths difference between the paths h and h’ is:
If N is an integer number, then constructive interference will occur, this means a maximum signal will be achieved at the receiving end. If N is an integer number of half wavelengths, then destructive interference will occur and a minimum signal will be received. Let us assume we are receiving a maximum signal for a given wavelength λ. If we start to change λ, this is the process called frequency modulation, N will no longer be a whole number and destructive interference will start to occur, meaning the signal will start to fade. Now we keep changing λ until a maximum signal is once again received. The means that for our new value λ’, our new value N’ is an also an integer number. If we have lengthened λ then we know that N’ is one less than N. Thus:
Rearranging for D gives:
As we know λ and λ’, we can calculate D. Using the approximation that ABC is an isosceles triangle, we can use our value of D to calculate the height of the reflecting layer. This method is a slightly simplified version of the method used by Appleton and his colleagues to work out a first value for the height of the ionosphere in 1924. In their experiment, they used the BBC
broadcasting station in Bournemouth
to vary the wavelengths of its emissions after the evening programs had finished. They installed a receiving station in Oxford to monitor the interference effects. The receiving station had to be in Oxford
as there was no suitable emitter at the right distance of about 100km from Cambridge in those days.
This frequency modulation method revealed that the point from which waves were being reflected was approximately 90 km. However, it did not establish that the waves were reflected from above, indeed they may have been coming from hills somewhere between Oxford and Bournemouth. The second method, which involved finding the angle of incidence of the reflected waves at the receiver, showed for sure that they were coming from above. Triangulations from this angle gave results for the height of reflection compatible with the frequency modulation method. We will not go into this method in detail because it involves fairly complex calculations using Maxwell’s electromagnetic theory.
Far from being conclusive, the success of the Oxford-Bournemouth experiment revealed a vast new field of study. It showed that there was indeed a reflecting layer high above the earth but it also posed many new questions. What was the constitution of this layer, how did it reflect the waves, was it the same all over the earth, why did its effects change so dramatically between day and night, did it change throughout the year? Appleton would spend the rest of his life answering these questions. He developed a magneto-ionic theory based on the previous work of Lorentz
and Maxwell
to model the workings of this part of the atmosphere. Using this theory and further experiments, he showed that the so called Kennelly-Heaviside layer
was heavily ionised and thus conducting. This led to the term ionosphere. He showed free electrons to be the ionising agents. He discovered that the layer could be penetrated by waves above a certain frequency and that this critical frequency could be used to calculate the electron density in the layer. However these penetrating waves would also be reflected back, but from a much higher layer. This showed the ionosphere had a much more complex structure than first anticipated. The lower level was labelled E – Layer, reflected longer wavelengths and was found to be at approximately 125 km. The high level, which had much higher electron density, was labelled F – Layer and could reflect much shorter wavelengths that penetrated the lower layer. It is situated 300 – 400 km above the earth’s surface. It is this which is often referred to as the Appleton Layer as is responsible for enabling most long range short wave telecommunication.
The magneto-ionic theory also allowed Appleton to explain the origin of the mysterious fadings heard on the radio around sunset. During the day, the light from the sun causes the molecules in the air to become ionised even at fairly low altitudes. At these low altitudes, the density of the air is great and thus the electron density of ionised air is very large. Due to this heavy ionisation, there is strong absorption of electromagnetic waves caused by ‘electron friction’. Thus in transmissions over any distance, there will be no reflections as any waves apart from the one at ground level will be absorbed rather than reflected. However, when the sun sets, the molecules slowly start to recombine with their electrons and the free electron density levels drop. This means absorption rates diminish and waves can be reflected with sufficient strengths to be noticed, leading to the interference phenomena we have mentioned. For these interference patterns to occur though, there must not simply be the presence of a reflected wave but a change in the reflected wave. Otherwise the interference is constant and fadings would not be heard. The received signal would simply be louder or softer than during the day. This suggests the height at which reflection happens must slowly change as the sun sets. Appleton found in fact that it increased as the sun set and then decreased as the sun rose until the reflected wave was too weak to record. This variation is compatible with the theory that ionisation is due to the sun’s influence. At sunset, the intensity of the sun’s radiation will be much less at the surface of the earth than it is high up in the atmosphere. This means ionic recombination will progress slowly from lower altitudes to higher ones and therefore the height at which waves are reflected slowly increases as the sun sets.
The basic idea behind Appleton’s work is so simple that it is hard to understand at first how he devoted almost all of his scientific career to its study. However, in the last couple of paragraphs some of the complexities of the subject have been introduced. Like many other fields, it is one that grows in intricacy the more it is studied. By the end of his life, ionospheric observatories had been set up all over the world to provide a global map of the reflecting layers. Links were found to the 11 year sunspot cycle and the Aurora Borealis, the magnetic storms that occur in high latitudes. This became particularly relevant during the second world war when the storms would lead to radio blackouts. Thanks to Appleton’s research, the periods when these would occur could be predicted and communication could be switched to wavelengths that would be least affected. RADAR
, another crucial wartime innovation, was one that came about thanks to Appleton’s work. On a very general level, his research consisted in determining the distance of reflecting objects from radio signal transmitters. This is exactly the idea of RADAR and the flashing dots that appear on the screen (a cathode ray tube) scanned by the circulating ‘searcher’ bar. This system was developed partly by Appleton as a new method, called the pulse method, to make ionospheric measurements. It was later adapted by Robert Watson-Watt
to detect aeroplanes. Nowadays, ionospheric data is important when communications with satellites are considered. The correct frequencies for these signals must be selected so that they actually reach the satellites without being reflected or deviated before.
In 1974 the Radio and Space Research Station
was renamed the Appleton Laboratory in honour of the man who had done so much to establish the UK as a leading force in ionospheric research, and had been involved with the station first as a researcher and then as secretary of its parent body, the Department of Scientific and Industrial Research.
IET Appleton lectures now at http://conferences.theiet.org/lectures/appleton/index.htm
Order of the British Empire
The Most Excellent Order of the British Empire is an order of chivalry established on 4 June 1917 by George V of the United Kingdom. The Order comprises five classes in civil and military divisions...
, KCB, FRS (6 September 1892 – 21 April 1965) was an English
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
.
Biography
Appleton was born in BradfordBradford
Bradford lies at the heart of the City of Bradford, a metropolitan borough of West Yorkshire, in Northern England. It is situated in the foothills of the Pennines, west of Leeds, and northwest of Wakefield. Bradford became a municipal borough in 1847, and received its charter as a city in 1897...
, West Yorkshire
West Yorkshire
West Yorkshire is a metropolitan county within the Yorkshire and the Humber region of England with a population of 2.2 million. West Yorkshire came into existence as a metropolitan county in 1974 after the passage of the Local Government Act 1972....
and educated at Hanson Grammar School
Hanson School
Hanson School is a comprehensive school in Bradford, West Yorkshire, England.-Admissions:Hanson School is situated between Bolton and Five Lane Ends. It is situated in an ethnically-white part of Bradford.-Head teacher:...
. At the age of 18 he won a scholarship to St John's College, Cambridge
St John's College, Cambridge
St John's College is a constituent college of the University of Cambridge. The college's alumni include nine Nobel Prize winners, six Prime Ministers, three archbishops, at least two princes, and three Saints....
. He graduated with a first class degree in Natural Sciences.
During the First World War he joined the West Riding Regiment
Duke of Wellington's Regiment
The Duke of Wellington's Regiment was an infantry regiment of the British Army, forming part of the King's Division.In 1702 Colonel George Hastings, 8th Earl of Huntingdon, was authorised to raise a new regiment, which he did in and around the city of Gloucester. As was the custom in those days...
, and later transferred to the Royal Engineers
Royal Engineers
The Corps of Royal Engineers, usually just called the Royal Engineers , and commonly known as the Sappers, is one of the corps of the British Army....
. After returning from active service in World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
, Appleton became assistant demonstrator in experimental physics at the Cavendish Laboratory
Cavendish Laboratory
The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the university's School of Physical Sciences. It was opened in 1874 as a teaching laboratory....
in 1920. He was professor of physics at King's College London
King's College London
King's College London is a public research university located in London, United Kingdom and a constituent college of the federal University of London. King's has a claim to being the third oldest university in England, having been founded by King George IV and the Duke of Wellington in 1829, and...
(1924–36) and professor of natural philosophy at Cambridge University
University of Cambridge
The University of Cambridge is a public research university located in Cambridge, United Kingdom. It is the second-oldest university in both the United Kingdom and the English-speaking world , and the seventh-oldest globally...
(1936–39). From 1939 to 1949 he was secretary of the Department of Scientific and Industrial Research
Department of Scientific and Industrial Research
Several countries have organizations called the Department of Scientific and Industrial Research, abbreviated DSIR.-United Kingdom:...
. Knighted in 1941, he received the 1947 Nobel Prize in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
for his contributions to the knowledge of the ionosphere
Ionosphere
The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere...
, which led to the development of radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
.
From 1949 until his death in 1965, he was Principal and Vice-Chancellor of the University of Edinburgh
University of Edinburgh
The University of Edinburgh, founded in 1583, is a public research university located in Edinburgh, the capital of Scotland, and a UNESCO World Heritage Site. The university is deeply embedded in the fabric of the city, with many of the buildings in the historic Old Town belonging to the university...
. In 1956, the BBC invited him to deliver the annual Reith Lectures. Across a series of six radio broadcasts, titled Science and the Nation, Appleton explored the many facets of scientific activity in Britain at the time.
Works
Appleton had observed that the strength of the radio signal from a transmitter on a frequency such as the medium wave band and over a path of a hundred miles or so was constant during the day but that it varied during the night. This led him to believe that it was possible that two radio signals were being received. One was traveling along the ground, and another was reflected by a layer in the upper atmosphere. The fading or variation in strength of the overall radio signal received resulted from the interference pattern of the two signals.The existence of a reflecting atmospheric layer was not in itself a completely new idea. Balfour Stewart had suggested the idea in the late nineteenth century to explain rhythmic changes in the earth’s magnetic field. More recently, in 1902, Oliver Heaviside
Oliver Heaviside
Oliver Heaviside was a self-taught English electrical engineer, mathematician, and physicist who adapted complex numbers to the study of electrical circuits, invented mathematical techniques to the solution of differential equations , reformulated Maxwell's field equations in terms of electric and...
and A.E. Kennelly had suggested such a hypothesis may explain the success Marconi had in transmitting his signals across the Atlantic. Calculations had shown that natural bending of the radio waves was not sufficient to stop them from simply “shooting off” into empty space before they reached the receiver.
Appleton thought the best place to look for evidence of the ionosphere was in the variations he believed it was causing around sunset in radio signal receptions. It was sensible to suggest these variations were due to the interference of two waves but an extra step to show that the second wave causing the interference (the first being the ground wave) was coming down from the ionosphere. The experiment he designed had two methods to show ionospheric influence and both allowed the height of the lower boundary of reflection (thus the lower boundary of the reflecting layer) to be determined. The first method was called frequency modulation and the second was to calculate the angle of arrival of the reflected signal at the receiving aerial.
The frequency modulation method exploits the fact that there is a path difference between the ground wave and the reflected wave, meaning they travel different distances from sender to receiver.
Let the distance AC travelled by the ground wave be h and the distance ABC travelled by the reflected wave h’. The path difference is:
The wavelength of the transmitted signal is λ . The number of wavelengths difference between the paths h and h’ is:
If N is an integer number, then constructive interference will occur, this means a maximum signal will be achieved at the receiving end. If N is an integer number of half wavelengths, then destructive interference will occur and a minimum signal will be received. Let us assume we are receiving a maximum signal for a given wavelength λ. If we start to change λ, this is the process called frequency modulation, N will no longer be a whole number and destructive interference will start to occur, meaning the signal will start to fade. Now we keep changing λ until a maximum signal is once again received. The means that for our new value λ’, our new value N’ is an also an integer number. If we have lengthened λ then we know that N’ is one less than N. Thus:
Rearranging for D gives:
As we know λ and λ’, we can calculate D. Using the approximation that ABC is an isosceles triangle, we can use our value of D to calculate the height of the reflecting layer. This method is a slightly simplified version of the method used by Appleton and his colleagues to work out a first value for the height of the ionosphere in 1924. In their experiment, they used the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
broadcasting station in Bournemouth
Bournemouth
Bournemouth is a large coastal resort town in the ceremonial county of Dorset, England. According to the 2001 Census the town has a population of 163,444, making it the largest settlement in Dorset. It is also the largest settlement between Southampton and Plymouth...
to vary the wavelengths of its emissions after the evening programs had finished. They installed a receiving station in Oxford to monitor the interference effects. The receiving station had to be in Oxford
Oxford
The city of Oxford is the county town of Oxfordshire, England. The city, made prominent by its medieval university, has a population of just under 165,000, with 153,900 living within the district boundary. It lies about 50 miles north-west of London. The rivers Cherwell and Thames run through...
as there was no suitable emitter at the right distance of about 100km from Cambridge in those days.
This frequency modulation method revealed that the point from which waves were being reflected was approximately 90 km. However, it did not establish that the waves were reflected from above, indeed they may have been coming from hills somewhere between Oxford and Bournemouth. The second method, which involved finding the angle of incidence of the reflected waves at the receiver, showed for sure that they were coming from above. Triangulations from this angle gave results for the height of reflection compatible with the frequency modulation method. We will not go into this method in detail because it involves fairly complex calculations using Maxwell’s electromagnetic theory.
Far from being conclusive, the success of the Oxford-Bournemouth experiment revealed a vast new field of study. It showed that there was indeed a reflecting layer high above the earth but it also posed many new questions. What was the constitution of this layer, how did it reflect the waves, was it the same all over the earth, why did its effects change so dramatically between day and night, did it change throughout the year? Appleton would spend the rest of his life answering these questions. He developed a magneto-ionic theory based on the previous work of Lorentz
Hendrik Lorentz
Hendrik Antoon Lorentz was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect...
and Maxwell
James Clerk Maxwell
James Clerk Maxwell of Glenlair was a Scottish physicist and mathematician. His most prominent achievement was formulating classical electromagnetic theory. This united all previously unrelated observations, experiments and equations of electricity, magnetism and optics into a consistent theory...
to model the workings of this part of the atmosphere. Using this theory and further experiments, he showed that the so called Kennelly-Heaviside layer
Kennelly-Heaviside layer
The Kennelly–Heaviside layer, named after Arthur Edwin Kennelly and Oliver Heaviside, also known as the E region or simply the Heaviside layer, is a layer of ionised gas occurring between roughly 90–150 km above the ground — one of several layers in the Earth's ionosphere...
was heavily ionised and thus conducting. This led to the term ionosphere. He showed free electrons to be the ionising agents. He discovered that the layer could be penetrated by waves above a certain frequency and that this critical frequency could be used to calculate the electron density in the layer. However these penetrating waves would also be reflected back, but from a much higher layer. This showed the ionosphere had a much more complex structure than first anticipated. The lower level was labelled E – Layer, reflected longer wavelengths and was found to be at approximately 125 km. The high level, which had much higher electron density, was labelled F – Layer and could reflect much shorter wavelengths that penetrated the lower layer. It is situated 300 – 400 km above the earth’s surface. It is this which is often referred to as the Appleton Layer as is responsible for enabling most long range short wave telecommunication.
The magneto-ionic theory also allowed Appleton to explain the origin of the mysterious fadings heard on the radio around sunset. During the day, the light from the sun causes the molecules in the air to become ionised even at fairly low altitudes. At these low altitudes, the density of the air is great and thus the electron density of ionised air is very large. Due to this heavy ionisation, there is strong absorption of electromagnetic waves caused by ‘electron friction’. Thus in transmissions over any distance, there will be no reflections as any waves apart from the one at ground level will be absorbed rather than reflected. However, when the sun sets, the molecules slowly start to recombine with their electrons and the free electron density levels drop. This means absorption rates diminish and waves can be reflected with sufficient strengths to be noticed, leading to the interference phenomena we have mentioned. For these interference patterns to occur though, there must not simply be the presence of a reflected wave but a change in the reflected wave. Otherwise the interference is constant and fadings would not be heard. The received signal would simply be louder or softer than during the day. This suggests the height at which reflection happens must slowly change as the sun sets. Appleton found in fact that it increased as the sun set and then decreased as the sun rose until the reflected wave was too weak to record. This variation is compatible with the theory that ionisation is due to the sun’s influence. At sunset, the intensity of the sun’s radiation will be much less at the surface of the earth than it is high up in the atmosphere. This means ionic recombination will progress slowly from lower altitudes to higher ones and therefore the height at which waves are reflected slowly increases as the sun sets.
The basic idea behind Appleton’s work is so simple that it is hard to understand at first how he devoted almost all of his scientific career to its study. However, in the last couple of paragraphs some of the complexities of the subject have been introduced. Like many other fields, it is one that grows in intricacy the more it is studied. By the end of his life, ionospheric observatories had been set up all over the world to provide a global map of the reflecting layers. Links were found to the 11 year sunspot cycle and the Aurora Borealis, the magnetic storms that occur in high latitudes. This became particularly relevant during the second world war when the storms would lead to radio blackouts. Thanks to Appleton’s research, the periods when these would occur could be predicted and communication could be switched to wavelengths that would be least affected. RADAR
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
, another crucial wartime innovation, was one that came about thanks to Appleton’s work. On a very general level, his research consisted in determining the distance of reflecting objects from radio signal transmitters. This is exactly the idea of RADAR and the flashing dots that appear on the screen (a cathode ray tube) scanned by the circulating ‘searcher’ bar. This system was developed partly by Appleton as a new method, called the pulse method, to make ionospheric measurements. It was later adapted by Robert Watson-Watt
Robert Watson-Watt
Sir Robert Alexander Watson-Watt, KCB, FRS, FRAeS is considered by many to be the "inventor of radar". Development of radar, initially nameless, was first started elsewhere but greatly expanded on 1 September 1936 when Watson-Watt became...
to detect aeroplanes. Nowadays, ionospheric data is important when communications with satellites are considered. The correct frequencies for these signals must be selected so that they actually reach the satellites without being reflected or deviated before.
In 1974 the Radio and Space Research Station
Radio Research Station
The Radio Research Station 1924 - August 31, 1979 at Ditton Park, Buckinghamshire, England was the UK government research laboratory which pioneered the regular observation of the ionosphere by ionosondes in continuous operation since September 20, 1932, and applied the ionosonde technology for the...
was renamed the Appleton Laboratory in honour of the man who had done so much to establish the UK as a leading force in ionospheric research, and had been involved with the station first as a researcher and then as secretary of its parent body, the Department of Scientific and Industrial Research.
Legacy
- the Rutherford Appleton LaboratoryRutherford Appleton LaboratoryThe Rutherford Appleton Laboratory is one of the national scientific research laboratories in the UK operated by the Science and Technology Facilities Council . It is located on the Harwell Science and Innovation Campus at Chilton near Didcot in Oxfordshire, United Kingdom...
- the Appleton TowerAppleton TowerAppleton Tower is a tower block in Edinburgh, Scotland, owned by the University of Edinburgh.- History :When the University developed the George Square site in the 1960s a huge swathe of Georgian Edinburgh was demolished, leading to accusations of cultural vandalism and megalomania...
at the University of EdinburghUniversity of EdinburghThe University of Edinburgh, founded in 1583, is a public research university located in Edinburgh, the capital of Scotland, and a UNESCO World Heritage Site. The university is deeply embedded in the fabric of the city, with many of the buildings in the historic Old Town belonging to the university... - the Appleton Science Building at Bradford College
- Appleton Academy, an up and coming new school, which will replace Wyke Manor School and High Fernley Primary School in the Wyke district of South BradfordBradfordBradford lies at the heart of the City of Bradford, a metropolitan borough of West Yorkshire, in Northern England. It is situated in the foothills of the Pennines, west of Leeds, and northwest of Wakefield. Bradford became a municipal borough in 1847, and received its charter as a city in 1897...
. This will be the first 'through-school' in West Yorkshire. - The crater AppletonAppleton (crater)Appleton is a heavily eroded lunar crater that lies in the northern hemisphere on the far side of the Moon. To the northwest are the craters Von Neumann and Campbel. The smaller Golovin lies to the northeast, while further to the southwest is the Mare Moscoviense.The crater wall and interior have...
on the MoonMoonThe Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
is named in his honour. - The Appleton Layer, which is the higher atmospheric ionized layer above the E-layer
- The annual Appleton Lecture at the Institute of Engineering Technology, IETInstitution of Engineering and TechnologyThe Institution of Engineering and Technology is a British professional body for those working in engineering and technology in the United Kingdom and worldwide. It was formed in 2006 from two separate institutions: the Institution of Electrical Engineers , dating back to 1871, and the...
. - Likely inspiration for the pseudonym Victor AppletonVictor AppletonVictor Appleton was a house pseudonym used by the Stratemeyer Syndicate, most famous for being associated with the Tom Swift series of books.The following series have been published under the Victor Appleton name:* Tom Swift, 1910–1941...
– the fictitious author of the Tom SwiftTom SwiftTom Swift is the name of the central character in five series of books, first appearing in 1910, totaling over 100 volumes, of American juvenile science fiction and adventure novels that emphasize science, invention and technology. The character was created by Edward Stratemeyer, the founder of...
series of novels - Appleton Academy in Bradford Wyke
Honours and awards
- Fellow of the Royal SocietyRoyal SocietyThe Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...
(1927) - Foreign Honorary Member of the American Academy of Arts and SciencesAmerican Academy of Arts and SciencesThe American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...
(1936) - Nobel Prize in PhysicsNobel Prize in PhysicsThe Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
(1947)
See also
- Kennelly–Heaviside layer
IET Appleton lectures now at http://conferences.theiet.org/lectures/appleton/index.htm
External links
- "Sir Edward Victor Appleton". nobelprize.org. Accessed October 21, 2007. (Citation: Nobel Prize in Physics: 1947, "for his investigations of the physics of the upper atmosphere especially for the discovery of the so-called Appleton layer." [Hyperlinked account. Provides link to BBC Historic Figures biography.]
- "Sir Edward Victor Appleton: Nobel Prize in Physics 1947" – Biography from Nobel Lectures, Physics 1942-1962 (Amsterdam: Elsevier Publishing Company, 1964). [Hyperlinked in previous entry.]
- "Sir Edward Victor Appleton (1892 - 1965): Appleton was an English physicist and Nobel prize winner who discovered the ionosphere." Historic Figures, bbc.co.uk. Accessed October 21, 2007. (Photograph of Appleton c. 1935 ©). [Provides link to Nobel Foundation account, listed above.]
- Nobelprize.org Biography
- Science and the Nation The BBC Reith Lectures, 1956, by Edward Appleton