Geophysics Research in PeruEdit
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What level or category is an article?Edit
This is an article in the "academia" domain of the collaborative editing “wikia” website. (http://academia.wikia.com/wiki). The tags (etiquetas) at the base of this article indicate the categories to which the article has been assigned. Tagging and indexing convert the journal into a database. Other tags can be added, e.g. geophysics. See the OJPS page for a list of categories. http://academia.wikia.com/wiki/Journal_of_Peruvian_Studies. The Minkapedia (minka - Quechua: working together, pedia – clas. Greek: education) category is for “collaborative” educational articles akin to the contents of university lectures / classes, but written collaboratively! The difference between Minkapedia and Wikipedia is the difference between a university lecture/class/course and handout (separata) and an encyclopaedia article. Good advice: don't over-categorise (claim a higher academic level than an article justifies) because the article will receive undue academic criticism (e.g. don’t tag your article “for peer review” when it’s a nice little magazine number. If you are just starting up a new collaborative piece call it a “stub”). Don't be too modest either. The category or tag is an indication to the reader about an article's academic level.
Focus of researchEdit
Peru is blessed and cursed by features of its geography and geology which have led to two special areas of research. These features are (a) its approximate position at the magnetic equator and (b) its vulnerability to earthquakes. Others could be added: some of the driest desert in the world, etc. However this article outlines the research being conducted in relation to (a) and (b), starting with the work of the Jicamarca radio observatory research station.
Jicamarca radio observatory research stationEdit
Initial stage 1960'sEdit
This section presents a film made by the US Department of Commerce - National Bureau of Standards (USDC-NBS), the partner organisation to the IGP (the Peruvian Geophysics Institute). Together they developed the original radio observatory on the Jicamarca site. The film is now over 40 years old. A few passages may strike the viewer as somewhat dated, as might be expected, but overall it has stood the test of time and provides a very useful insight into the construction and development phase (and to aspects of the Peru of that era). The film has been split into 3 YouTube videos, subtitles added and the videos embedded below. A version in Spanish is available from the YouTube site.
The original “Jicamarca videos"Edit
The internet addresses (URL's) of the Spanish version of these videos are given at the end of this section
(00.00 to 03.00 minutes.)The first video explains why, in the 1960’s, scientific research was reaching out beyond the atmosphere and why the NBS was searching for a research partner (and site) on or near the magnetic equator. It explains why the research problems start around 300 kms from the Earth’s surface. At this distance short wave radio signals are reflected back to Earth (see video) – useful but this limits radio-based research into and beyond the ionosphere (see definition). The then relatively new rockets and satellites could help but provided only “snapshots”. A new research technique using scatter radar was developed but the USDC-NBS needed a site for the radar observatory.
(03.00 minutes) The video then provides a more technical explanation. It may help if you check out the concept of free electrons. Scientists wanted to know how far above the denser F-layer free electrons extended.
(05.08 minutes) Explanation of the incoherent scatter radar research techniques developed by Dr Kenneth Bowles and his team at the Boulder, Colorado Laboratories of the USDC-NBS: provides a facinating insight into the history of science at this point.
(06.47 minutes)The video now explains why a site near the magnetic equator was chosen – the chemical composition of the ionosphere could be measured more precisely.
(08.24 minutes) Lima the capital of Peru then examined. (08.29 end of first video)
(00.00 to 00.57) Explains various factors favouring Lima as the site for the research facility. The street scenes will be nostalgic for some. Note the tram (streetcar) lines. This was the time of President Kennedy and much of Latin America, including Peru, was politically closer to the United States. Some of the areas filmed, especially the city centre, have never really regained the prosperity which they had enjoyed until then. So this footage is fascinating for many reasons.
(00.58 minutes) We are introduced to Peru’s Instituto Geofísico and via a train journey on the Central Railway to the Institute’s observatory near Huancayo (also shown).
(03.05 minutes) Back to the coast to search for a specific site: dry, and protected from radio interference by surrounding hills.
(04.12 minutes) A treaty is signed between Peru and the US. Work is started August 1960. First the diversion dam to protect the site from sudden mud flows and flash floods.
(05.12 minutes) Work proceeds on the antenna.
(06.25 minutes) Life for the project’s families. 10 Bureau families. Chaclacayo. Speaking Spanish.
(07.53 minutes) Back to construction at the Jicamarca site (08.00) End Part 2.
(00.00 to 00.53) The transmitter. The training of Peruvian engineers and technicians.
(00.54 minutes) The transformer room producing 3750 KW of electrical power. The condenser bank.
(01.36 minutes) The capacitors (bank) have a capacitance of 1000 micro-farads. Can be discharged in a powerful electrical pulse rated up to 20,000 jules.
(01.46 minutes) The four red amplifiers used in the transmitter. Up to 6 million watts of radio frequency power.
(02.21 minutes) The water cooling system and the air cooled tunnels for cabling and coaxial “tubes”.
(03.00 minutes) The monitoring equipment. Much of the equipment above has stood the test of time and is still providing service. However the monitoring equipment is now largely digital.
The full YouTube URL's are given below
English ver. Part 1/3 : http://www.youtube.com/watch?v=6g4RNW9Ro84
English ver. Part 2/3 : http://www.youtube.com/watch?v=Y9YHQw-XtO0
English ver. Part 3/3 : http://www.youtube.com/watch?v=EmVpCWQawDo
Parte 1/3 en Español: http://www.youtube.com/watch?v=cRm3v3Om4pY
Parte 2/3 en Español: http://www.youtube.com/watch?v=G5Db6HGwLTw
Parte 3/3 en Español: http://www.youtube.com/watch?v=_04ITHSSPDg
The wikipedia encyclopaedia entry (Spanish)Edit
(See above for clarification on the different focuses of Wikipedia and Minkapedia. Go to original wikipedia article for links (in red) to work).
El Radio Observatorio de Jicamarca es una estación ecuatorial de la cadena de radio observatorios de dispersión incoherente (ISR, sus siglas en inglés) ubicada en Perú. Se ubica a 25 kilómetros, media hora en automóvil, al este de Lima y su altitud aproximada es de 500 msnm. Su ángulo de inclinación es de apenas 1º, pero varía de acuerdo a la estación del año.
Situado en el ecuador magnético de la Tierra, a 25 km del centro de Lima, el Radio Observatorio de Jicamarca (ROJ) es el radar científico más grande del mundo. Su transmisor utiliza una antena de 90 mil metros cuadrados –ocho canchas de fútbol— para iluminar el espacio con destellos de radio de hasta 6 millones de vatios.
Jicamarca fue el primer Radar de Dispersión Incoherente(ISR: Incoherent Scatter Radar) especialmente diseñado para estudiar la ionosfera, la capa exterior de la atmósfera terrestre, una región de partículas eléctricamente cargadas que envuelve el planeta desde los 80,000 metros hasta miles de kilómetros de altitud. El ROJ ha obtenido registros de la ionosfera hasta 10,000 km sobre el nivel del mar.
Fue inaugurado el 27 de abril de 1961, construido por el Laborarotio central de Radio Propagación de la National Bureau of Standards (NBS). En 1969, los nuevos dueños del observatorio (Environmental Science Service Administration, ESSA) transfirió el mando al Instituto Geofísico del Perú, que había brindado ayuda en la construcción y puesta en funcionamiento del Observatorio.
- Una digisonda.
- Un magnenómetro.
- Radares VHF.
- Un radar de detección especular de meteoros.
The joule is the derived unit of energy in the International System of Units. It is defined as - One joule is the amount of energy required to perform the following actions: The work done by a force of one newton traveling through a distance of one meter; The work required to move an electric charge of one coulomb through an electrical potential difference of one volt; or one coulomb volt, with the symbol C·V; The work done to produce the power of one watt continuously for one second; or one watt second (compare kilowatt hour), with the symbol W·s. Thus a kilowatt hour is 3,600,000 joules or 3.6 megajoules; The kinetic energy of a 2 kilogram (kg) mass (m) moving at a velocity of 1 meter per second (m/s). The energy is linear in the mass but quadratic in the velocity, being given by E = ½mv², energy (E) is equal to 1/2 of mass (m) multiplied by velocity (v) squared.
The ionosphere is the uppermost part of the atmosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on the Earth. It is located in the Thermosphere.