|
Michiel Daniel Overbeek
Michiel Daniel Overbeek (15 September 1920 in Ermelo, Mpumalanga, South Africa – 19 July 2001 in Johannesburg), also known as Danie Overbeek, was a South African amateur astronomer and one of the most prolific variable star observers. Life He studied in a Mining and Metallurgy program at the University of the Witwatersrand. During the Second World War he served in the South African Air Force and was awarded the Africa Star and mentioned in Dispatches. After the war he worked for South African Airways and South African Railways. In 1945 he married Jean Mary Preddy, with whom he had four children. She died in 1985. Astronomy Daniel Overbeek's serious interest in astronomy dates back to 1951, when he started observing occultations and variable stars. In 1958 he earned a B.Sc. degree in mathematics and astronomy from the University of South Africa. In his life he contributed 287,240 observations to the American Association of Variable Star Observers (AAVSO) International Database, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ermelo, Mpumalanga
Ermelo () is the educational, industrial and commercial town of the 7,750 km2 Gert Sibande District Municipality in Mpumalanga province, Republic of South Africa. It is both a mixed agriculture and mining region. It is located 210 km east of Johannesburg. History Some of the earliest inhabitants of the area were the Leghoya people. Not much is known about them, but ruins of their settlements dating back to c.1400 can be found in the area. During the mid-1800s, the area prior to the formation as a village, was an ''outspan'' area for resting teams of draw animals transporting goods across the region mainly due to the water of the small lakes dotting the area. Modern Ermelo was founded by Dutch Reformed Church Reverend Frans Lion Cachet (1835–1899). He would minister to the many farms in the area. A congregation was started by Cachet in 1870, and was recognised by the 5th annual general meeting of the church in April 1872. The town was formed on the farm ''Nooitgedacht'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of South Africa
The University of South Africa (UNISA), known colloquially as Unisa, is the largest university system in South Africa by enrollment. It attracts a third of all higher education students in South Africa. Through various colleges and affiliates, UNISA has over 400,000 students, including international students from 130 countries worldwide, making it one of the world's mega universities and the only such university in Africa. As a comprehensive university, Unisa offers both vocational and academic programmes, many of which have received international accreditation, as well as an extensive geographical footprint, giving their students recognition and employability in many countries the world over. The university lists many notable South Africans among its alumni, including two Nobel prize winners: Nelson Mandela, the first democratically elected president of South Africa and Archbishop Desmond Tutu. Founded in 1873 as the University of the Cape of Good Hope, the University of Sout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Achievement Award Of Astronomical Society Of The Pacific
The Gordon Myers Amateur Achievement Award, known until 2018 as the Amateur Achievement Award of the Astronomical Society of the Pacific, is one of nine annual astronomical awards managed by the Astronomical Society of the Pacific. It recognizes "significant contributions to astronomy or amateur astronomy by those not employed in the field of astronomy in a professional capacity." The contributions can be done in the fields of both observational astronomy or astronomical technologies. The award has been given to amateur astronomers from various countries since 1979 and has become one of the most geographically diverse astronomical awards. Award winners receive a commemorative plaque, which is presented at the Annual Meeting Awards Banquet. The monetary value of the award is US$500. Candidates can be nominated by any member of the astronomical community (with the exception of the nominees themselves and their families) and the nominations should be accompanied by other letters of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merit Award
The NIH MERIT award (Method To Extend Research in Time) Award (R37) was created by the National Institutes of Health The National Institutes of Health, commonly referred to as NIH (with each letter pronounced individually), is the primary agency of the United States government responsible for biomedical and public health research. It was founded in the late ... in 1986. It is a prestigious award designed to provide stable, long-term funding support to outstanding, experienced investigators whose productivity is distinctly superior and who are deemed highly likely to continue to perform their research activities in an outstanding manner. The MERIT award provided funding for 5 years and could be renewed for up to 10 years. Unlike most NIH grant awards, the MERIT award can not be applied for by the investigator. Researchers submitting an R01 that receives a fundable score are considered for the award. In 2018, the NIH began awarding MERIT awards to "Early Stage Investigators", ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill Medal
The Astronomical Society of Southern Africa (ASSA), formed in 1922, is a widespread body consisting of both amateur and professional astronomers. There are eight autonomous centres throughout Southern Africa. History The Cape Astronomical Association was established in 1912, shortly after the 1910 appearance of Halley's Comet. Sydney Samuel Hough, HM Astronomer at the Cape, was chosen President. In 1918, the Johannesburg Astronomical Association was created, with RTA Innes, Union Astronomer, as President. In 1922 it was decided to merge the two Associations to form the Astronomical Society of South Africa after an invitation from the Cape Association. In 1956 the name was amended to become the Astronomical Society of Southern Africa. Membership and publications Membership is open to all interested persons. The Society publishes the on-line peer-reviewed journal ''Monthly Notes of the Astronomical Society of Southern Africa'' (''MNASSA''). In addition to ''MNASSA'', the annual ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Society Of Southern Africa
The Astronomical Society of Southern Africa (ASSA), formed in 1922, is a widespread body consisting of both amateur and professional astronomers. There are eight autonomous centres throughout Southern Africa. History The Cape Astronomical Association was established in 1912, shortly after the 1910 appearance of Halley's Comet. Sydney Samuel Hough, HM Astronomer at the Cape, was chosen President. In 1918, the Johannesburg Astronomical Association was created, with RTA Innes, Union Astronomer, as President. In 1922 it was decided to merge the two Associations to form the Astronomical Society of South Africa after an invitation from the Cape Association. In 1956 the name was amended to become the Astronomical Society of Southern Africa. Membership and publications Membership is open to all interested persons. The Society publishes the on-line peer-reviewed journal ''Monthly Notes of the Astronomical Society of Southern Africa'' (''MNASSA''). In addition to ''MNASSA'', the annual ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sudden Ionospheric Disturbance
A sudden ionospheric disturbance (SID) is any one of several ionospheric perturbations, resulting from abnormally high ionization/ plasma density in the D region of the ionosphere and caused by a solar flare and/or solar particle event (SPE). The SID results in a sudden increase in radio-wave absorption that is most severe in the upper medium frequency (MF) and lower high frequency (HF) ranges, and as a result often interrupts or interferes with telecommunications systems. Discovery The ''Dellinger effect'', or sometimes ''Mögel–Dellinger effect'', is another name for a sudden ionospheric disturbance. The effect was discovered by John Howard Dellinger around 1935 and also described by the German physicist (1900-1944) in 1930. The fadeouts are characterized by sudden onset and a recovery that takes minutes or hours. Cause When a solar flare occurs on the Sun a blast of intense ultraviolet (UV) and x-ray (sometimes even gamma ray) radiation hits the dayside of the Earth after ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismograph
A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed digitally—is a seismogram. Such data is used to locate and characterize earthquakes, and to study the Earth's internal structure. Basic principles A simple seismometer, sensitive to up-down motions of the Earth, is like a weight hanging from a spring, both suspended from a frame that moves along with any motion detected. The relative motion between the weight (called the mass) and the frame provides a measurement of the vertical ground motion. A rotating drum is attached to the frame and a pen is attached to the weight, thus recording any ground motion in a seismogram. Any movement from the ground moves the frame. The mass tends not to m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetometer
A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, one that measures the direction of an ambient magnetic field, in this case, the Earth's magnetic field. Other magnetometers measure the magnetic dipole moment of a magnetic material such as a ferromagnet, for example by recording the effect of this magnetic dipole on the induced current in a coil. The first magnetometer capable of measuring the absolute magnetic intensity at a point in space was invented by Carl Friedrich Gauss in 1833 and notable developments in the 19th century included the Hall effect, which is still widely used. Magnetometers are widely used for measuring the Earth's magnetic field, in geophysical surveys, to detect magnetic anomalies of various types, and to determine the dipole moment of magnetic materials. In an air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismology
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. It also includes studies of earthquake environmental effects such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, glacial, fluvial, oceanic, atmospheric, and artificial processes such as explosions. A related field that uses geology to infer information regarding past earthquakes is paleoseismology. A recording of Earth motion as a function of time is called a seismogram. A seismologist is a scientist who does research in seismology. History Scholarly interest in earthquakes can be traced back to antiquity. Early speculations on the natural causes of earthquakes were included in the writings of Thales of Miletus (c. 585 BCE), Anaximenes of Miletus (c. 550 BCE), Aristotle (c. 340 BCE), and Zha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Magnetic Field
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic field is generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in Earth's outer core: these convection currents are caused by heat escaping from the core, a natural process called a geodynamo. The magnitude of Earth's magnetic field at its surface ranges from . As an approximation, it is represented by a field of a magnetic dipole currently tilted at an angle of about 11° with respect to Earth's rotational axis, as if there were an enormous bar magnet placed at that angle through the center of Earth. The North geomagnetic pole actually represents the South pole of Earth's magnetic field, and conversely the South geomagnetic pole corresponds to the north pole of Earth's magnetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
