http://www.hist-geo-space-sci.net/ History of Geo- and Space Sciences Latest Articlesenhttp://www.hist-geo-space-sci.net/3/117/2012/<b>Iceland spar and its legacy in science</b><br /><br />History of Geo- and Space Sciences, 3, 117-126, 2012<br /><br />Author(s): L. Kristjánsson<br /><br />In the late 17th century, Rasmus Bartholin and Christiaan Huygens investigated a curious optical property of crystals found at Helgustaðir in Eastern Iceland. This property which has been called double refraction, revealed in the 19th century a new aspect of light which turned out to be very useful as a probe of the internal structure of matter. Clear specimens of these crystals, an unusually pure variety of calcite, have since around 1780 been known as ''Iceland spar''. Few if any other localities yielding calcite crystals of comparable size and quality were discovered before 1900, and no alternatives for use in precision optical instrumentation were developed until the 1930s. Hundreds of tons of calcite were exported from Helgustaðir, mostly between 1850 and 1925. However, little information has been found on trading routes for the material of optical quality, so that some enigmas remain regarding its supply-demand situation. A study of the scientific literature in the period up to 1930 has revealed that results obtained with the aid of Iceland spar accelerated progress within the earth sciences (in mineralogy and petrology), physics, chemistry, and biology, even by decades. This has also influenced the development of technology and of medicine in various direct and indirect ways.Wed, 16 May 2012 00:00:00 +0200http://www.hist-geo-space-sci.net/3/113/2012/<b>Book Review<br> From Hooke and Leibniz to Rouelle and Lavoisier, the eventful world of early geologists. A review of ''Studies on Eighteenth-Century Geology, a Selection of Papers by Rhoda Rappaport''</b><br /><br />History of Geo- and Space Sciences, 3, 113-115, 2012<br /><br />Author(s): P. Richet<br /><br />Fri, 11 May 2012 00:00:00 +0200http://www.hist-geo-space-sci.net/3/99/2012/<b>Rectification of the ancient geographic coordinates in Ptolemy's Geographike Hyphegesis</b><br /><br />History of Geo- and Space Sciences, 3, 99-112, 2012<br /><br />Author(s): C. Marx<br /><br />A multitude of the ancient places given by Ptolemy in his <I>Geography</I> (~150 AD) are so far unknown. One of the main problems of their identification are the errors of the given ancient coordinates. The different kinds of errors are illustrated by examples. A new geodetic-statistical analysis method is described, by which groups of places with homogeneous systematic errors and places with gross errors can be determined. Based on a transformation function describing the systematic errors, presumable modern coordinates of unknown places can be computed. That, in conjunction with further information, can make possible their identification. A test of the analysis method is carried out on a complex simulated example and shows its practicability. The analysis method has been applied within an interdisciplinary research project on Ptolemy's <I>Geography</I>. Further developments of the method are imaginable to make it accessible for related data diagnostics.Wed, 28 Mar 2012 00:00:00 +0200http://www.hist-geo-space-sci.net/3/87/2012/<b>Notes on historical aspects on the earliest known observations of noctilucent clouds</b><br /><br />History of Geo- and Space Sciences, 3, 87-97, 2012<br /><br />Author(s): P. Dalin, N. Pertsev, and V. Romejko<br /><br />The present paper considers historical aspects of the earliest known observations of noctilucent clouds (NLCs). The 1884 and 1885 are discussed by considering important historical citations by the pioneers of the earliest known observations of noctilucent clouds. For the first time in NLC studies, we consider seven major volcanic eruptions: Laki in 1783, Mount St. Helens in 1800, Tambora in 1815, Galunggung in 1822, Cosigüina in 1835, Shiveluch in 1854 and Askja in 1875. These all preceded the catastrophic 1883 eruption of Krakatoa, which despite having a lesser magnitude than Tambora in 1815, had pronounced effects on the atmosphere. These eruptions represent possible triggers for the appearance of NLCs. For the first time, we publish an unknown, in English-speaking literature, historical fact on the first determinations of the altitude of noctilucent clouds made by two Russian astronomers V. K. Tseraskii and A. A. Belopolskii on 26 June 1885, who managed to infer the altitude of the clouds in the range of 73&ndash;83 km, that is, for the first time, demonstrating the possible existence of the clouds at great altitudes in the Earth's atmosphere. Moreover, V. K. Tseraskii was the first observer to photograph noctilucent clouds in 1885 or 1886, which is 1&ndash;2 yr before the German astronomer O. Jesse, who owns the first published images of noctilucent clouds. The photographs made by V. K. Tseraskii, unfortunately, did not reach us.Tue, 27 Mar 2012 00:00:00 +0200http://www.hist-geo-space-sci.net/3/75/2012/<b>Edwin James' and John Hinton's revisions of Maclure's geologic map of the United States</b><br /><br />History of Geo- and Space Sciences, 3, 75-86, 2012<br /><br />Author(s): K. R. Aalto<br /><br />William Maclure's pioneering geologic map of the eastern United States, published first in 1809 with <i>Observations on the Geology of the United States</i>, provided a foundation for many later maps &ndash; a template from which geologists could extend their mapping westward from the Appalachians. Edwin James, botanist, geologist and surgeon for the 1819/1820 United States Army western exploring expedition under Major Stephen H. Long, published a full account of this expedition with map and geologic sections in 1822&ndash;1823. In this he extended Maclure's geology across the Mississippi Valley to the Colorado Rockies. John Howard Hinton (1791&ndash;1873) published his widely read text: <i>The History and Topography of the United States</i> in 1832, which included a compilations of Maclure's and James' work in a colored geologic map and vertical sections. All three men were to some degree confounded in their attempts to employ Wernerian rock classification in their mapping and interpretations of geologic history, a common problem in the early 19th Century prior to the demise of Neptunist theory and advent of biostratigraphic techniques of correlation. However, they provided a foundation for the later, more refined mapping and geologic interpretation of the eastern United States.Wed, 14 Mar 2012 00:00:00 +0100http://www.hist-geo-space-sci.net/3/73/2012/<b>Robert Helliwell, pioneer of whistler-mode research</b><br /><br />History of Geo- and Space Sciences, 3, 73-74, 2012<br /><br />Author(s): D. L. Carpenter and U. S. Inan<br /><br />No abstract available.Wed, 14 Mar 2012 00:00:00 +0100http://www.hist-geo-space-sci.net/3/53/2012/<b>Sophus Peter Tromholt: an outstanding pioneer in auroral research</b><br /><br />History of Geo- and Space Sciences, 3, 53-72, 2012<br /><br />Author(s): K. Moss and P. Stauning<br /><br />The Danish school teacher Sophus Peter Tromholt (1851&ndash;1896) was self-taught in physics, astronomy, and auroral sciences. Still, he was one of the brightest auroral researchers of the 19th century. He was the first scientist ever to organize and analyse correlated auroral observations over a wide area (entire Scandinavia) moving away from incomplete localized observations. Tromholt documented the relation between auroras and sunspots and demonstrated the daily, seasonal and solar cycle-related variations in high-latitude auroral occurrence frequencies. Thus, Tromholt was the first ever to deduce from auroral observations the variations associated with what is now known as the auroral oval termed so by Khorosheva (1962) and Feldstein (1963) more than 80 yr later. He made reliable and accurate estimates of the heights of auroras several decades before this important issue was finally settled through Størmer's brilliant photographic technique. In addition to his three major scientific works (Tromholt, 1880a, 1882a, and 1885a), he wrote numerous short science notes and made huge efforts to collect historical auroral observations (Tromholt, 1898). Furthermore, Tromholt wrote a large number of popular science articles in newspapers and journals and made lecture tours all over Scandinavia and Germany, contributing to enhance the public educational level and awareness. He devoted most of his life to auroral research but as a self-taught scientist, he received little acclaim within the contemporary academic scientific society. With his non-academic background, trained at a college of education &ndash; not a university &ndash; he was never offered a position at a university or a research institution. However, Sophus Tromholt was an outstanding pioneer in auroral research.Wed, 07 Mar 2012 00:00:00 +0100http://www.hist-geo-space-sci.net/3/47/2012/<b>History of EISCAT – Part 3: The early history of EISCAT in Norway</b><br /><br />History of Geo- and Space Sciences, 3, 47-52, 2012<br /><br />Author(s): O. Holt<br /><br />The paper describes the Norwegian participation in the EISCAT project during the first years of planning the facility. This includes obtaining the support of the relevant research groups as well as the possible funding agencies. Attention is also given to strengthening the competence and capacity of the potential user groups, along with taking part in the cooperation with the participating groups in other countries.Tue, 06 Mar 2012 00:00:00 +0100http://www.hist-geo-space-sci.net/3/33/2012/<b>Father Secchi and the first Italian magnetic observatory</b><br /><br />History of Geo- and Space Sciences, 3, 33-45, 2012<br /><br />Author(s): N. Ptitsyna and A. Altamore<br /><br />The first permanent magnetic observatory in Italy was built in 1858 by Pietro Angelo Secchi, a Jesuit priest who made significant contributions in a wide variety of scientific fields, ranging from astronomy to astrophysics and meteorology. In this paper we consider his studies in geomagnetism, which have never been adequately addressed in the literature. We mainly focus on the creation of the magnetic observatory on the roof of the church of Sant'Ignazio, adjacent to the pontifical university, known as the Collegio Romano. From 1859 onwards, systematic monitoring of the geomagnetic field was conducted in the Collegio Romano Observatory, for long the only one of its kind in Italy. We also look at the magnetic instruments installed in the observatory, which were the most advanced for the time, as well as scientific studies conducted there in its early years.Tue, 28 Feb 2012 00:00:00 +0100http://www.hist-geo-space-sci.net/3/1/2012/<b>Spiral structures and regularities in magnetic field variations and auroras</b><br /><br />History of Geo- and Space Sciences, 3, 1-31, 2012<br /><br />Author(s): Y. I. Feldstein, L. I. Gromova, M. Förster, and A. E. Levitin<br /><br />The conception of spiral shaped precipitation regions, where solar corpuscles penetrate the upper atmosphere, was introduced into geophysics by C. Störmer and K. Birkeland at the beginning of the last century. Later, in the course of the XX-th century, spiral distributions were disclosed and studied in various geophysical phenomena. Most attention was devoted to spiral shapes in the analysis of regularities pertaining to the geomagnetic activity and auroras. <br><br> We review the historical succession of perceptions about the number and positions of spiral shapes, that characterize the spatial-temporal distribution of magnetic disturbances. We describe the processes in the upper atmosphere, which are responsible for the appearance of spiral patterns. We considered the zones of maximal aurora frequency and of maximal particle precipitation intensity, as offered in the literature, in their connection with the spirals. <br><br> We discuss the current system model, that is closely related to the spirals and that appears to be the source for geomagnetic field variations during magnetospheric substorms and storms. The currents in ionosphere and magnetosphere constitute together with field-aligned (along the geomagnetic field lines) currents (FACs) a common 3-D current system. At ionospheric heights, the westward and eastward electrojets represent characteristic elements of the current system. The westward electrojet covers the longitudinal range from the morning to the evening hours, while the eastward electrojet ranges from afternoon to near-midnight hours. The polar electrojet is positioned in the dayside sector at cusp latitudes. All these electrojets map along the magnetic field lines to certain plasma structures in the near-Earth space. The first spiral distribution of auroras was found based on observations in Antarctica for the nighttime-evening sector (N-spiral), and later in the nighttime-evening (N-spiral) and morning (M-spiral) sectors both in the Northern and Southern Hemispheres. The N- and M-spirals drawn in polar coordinates form an oval, along which one observes most often auroras in the zenith together with a westward electrojet. <br><br> The nature of spiral distributions in geomagnetic field variations was unabmibuously interpreted after the discovery of the spiral's existence in the auroras had been established and this caused a change from the paradigm of the auroral zone to the paradigm of the auroral oval. Zenith forms of auroras are found within the boundaries of the auroral oval. The oval is therefore the region of most frequent precipitations of corpuscular fluxes with auroral energy, where anomalous geophysical phenomena occur most often and with maximum intensity. <br><br> S. Chapman and L. Harang identified the existence of a discontinuity at auroral zone latitudes (&Phi; &sim; 67&deg;) around midnight between the westward and eastward electrojets, that is now known as the Harang discontinuity. After the discovery of the auroral oval and the position of the westward electrojet along the oval, it turned out, that there is no discontinuity at a fixed latitude between the opposite electrojets, but rather a gap, the latitude of which varies smoothly between &Phi; &sim; 67&deg; at midnight and &Phi; &sim; 73&deg; at 20:00 MLT. In this respect the term ''Harang discontinuity'' represents no intrinsic phenomenon, because the westward electrojet does not experience any disruption in the midnight sector but continues without breaks from dawn to dusk hours.Tue, 21 Feb 2012 00:00:00 +0100http://www.hist-geo-space-sci.net/2/123/2011/<b>History of EISCAT – Part 2: The early history of EISCAT in Finland</b><br /><br />History of Geo- and Space Sciences, 2, 123-128, 2011<br /><br />Author(s): J. Oksman<br /><br />The idea of a Nordic incoherent scatter facility, proposed by Bengt Hultqvist, was for the first time discussed among representatives of the three Nordic countries Norway, Sweden and Finland in 1969 in Oulu, Finland. In the years to follow, when other countries joined in and the plans of the facility to be built gradually received concrete forms, Finland participated in the planning work, in spite of the large costs to be expected. When in negotiations with the Nordic partners in 1975 the share of Finland in EISCAT was reduced to five per cent and when the existing facilities and personnel at Sodankylä could be taken into account in the Finnish share, the Academy of Finland was finally ready to join EISCAT.Mon, 19 Dec 2011 00:00:00 +0100http://www.hist-geo-space-sci.net/2/115/2011/<b>History of EISCAT – Part 1: On the early history of EISCAT with special reference to the Swedish part of it</b><br /><br />History of Geo- and Space Sciences, 2, 115-121, 2011<br /><br />Author(s): B. Hultqvist<br /><br />The paper describes the early history of EISCAT, from the very first ideas and Nordic contacts in the late 1960s to the end of the main development phase, when the facility had become a very advanced and reliable research instrument and its users had developed full competence in the second half of the 1980s. The preparation of the ''Green Book'', the Beynon meeting in London in 1973 and the activities started there, the first EISCAT Council meeting, the ''technical period'' 1976&ndash;1981, the inauguration in 1981 and the decade of improvements in most of the 1980s are described as seen from the Swedish point of view.Mon, 19 Dec 2011 00:00:00 +0100http://www.hist-geo-space-sci.net/2/113/2011/<b>Introduction "The history of ionospheric radars"</b><br /><br />History of Geo- and Space Sciences, 2, 113-114, 2011<br /><br />Author(s): R. Pellinen and A. Brekke<br /><br />Tue, 13 Dec 2011 00:00:00 +0100http://www.hist-geo-space-sci.net/2/99/2011/<b>Roald Amundsen's contributions to our knowledge of the magnetic fields of the Earth and the Sun</b><br /><br />History of Geo- and Space Sciences, 2, 99-112, 2011<br /><br />Author(s): A. Egeland and C. S. Deehr<br /><br />Roald Amundsen (1872&ndash;1928) was known as one of the premier polar explorers in the golden age of polar exploration. His accomplishments clearly document that he has contributed to knowledge in fields as diverse as ethnography, meteorology and geophysics. In this paper we will concentrate on his studies of the Earth's magnetic field. With his unique observations at the polar station Gjøahavn (geographic coordinates 68&deg;37'10'' N; 95&deg;53'25'' W), Amundsen was first to demonstrate, without doubt, that the north magnetic dip-pole does not have a permanent location, but steadily moves its position in a regular manner. In addition, his carefully calibrated measurements at high latitudes were the first and only observations of the Earth's magnetic field in the polar regions for decades until modern polar observatories were established. After a short review of earlier measurements of the geomagnetic field, we tabulate the facts regarding his measurements at the observatories and the eight field stations associated with the Gjøa expedition. The quality of his magnetic observations may be seen to be equal to that of the late 20th century observations by subjecting them to analytical techniques showing the newly discovered relationship between the diurnal variation of high latitude magnetic observations and the direction of the horizontal component of the interplanetary magnetic field (IMF <i><b>B</b></i>_<i>y</i>). Indeed, the observations at Gjøahavn offer a glimpse of the character of the solar wind 50 yr before it was known to exist. Our motivation for this paper is to illuminate the contributions of Amundsen as a scientist and to celebrate his attainment of the South Pole as an explorer 100 yr ago.Sat, 10 Dec 2011 00:00:00 +0100http://www.hist-geo-space-sci.net/2/97/2011/<b>Book Review "In the Shadow of Melting Glaciers. Climate change and Andean Society"</b><br /><br />History of Geo- and Space Sciences, 2, 97-98, 2011<br /><br />Author(s): A. Rivera<br /><br />Mon, 17 Oct 2011 00:00:00 +0200http://www.hist-geo-space-sci.net/2/89/2011/<b>Johann Christian Heuson, a little-known auroral scholar of the early 18th century</b><br /><br />History of Geo- and Space Sciences, 2, 89-95, 2011<br /><br />Author(s): K. Schlegel and S. Silverman<br /><br />Heuson published two booklets of observations of the aurora of 17/18 February, 1/2 March 1721, and 16/17 November 1729 together with contemporary thoughts about the subject. His work characterizes him as a well-educated scholar familiar with contemporary auroral observations and theories. Heuson rejects views of the aurora as an omen or portent of divine wrath, but explains the aurora as a natural phenomenon and is thus in line with other well-known auroral scholars of that time.Tue, 09 Aug 2011 00:00:00 +0200http://www.hist-geo-space-sci.net/2/87/2011/<b>Reply to Comment on "Danish auroral science history" by P. Stauning in Hist. Geo Space Sci., 2, 1–28, 2011</b><br /><br />History of Geo- and Space Sciences, 2, 87-87, 2011<br /><br />Author(s): P. Stauning<br /><br />No abstract available.Tue, 02 Aug 2011 00:00:00 +0200http://www.hist-geo-space-sci.net/2/85/2011/<b>Comment on "Danish auroral science history" by P. Stauning in Hist. Geo Space Sci., 2, 1–28, 2011</b><br /><br />History of Geo- and Space Sciences, 2, 85-86, 2011<br /><br />Author(s): T. S. Jørgensen<br /><br />No abstract available.Tue, 02 Aug 2011 00:00:00 +0200http://www.hist-geo-space-sci.net/2/83/2011/<b>"Historian of geomagnetism and aeronomy" Obituary – Dr. Wilfried Schröder</b><br /><br />History of Geo- and Space Sciences, 2, 83-84, 2011<br /><br />Author(s): K. Schlegel and G. Gregori<br /><br />No abstract available.Wed, 29 Jun 2011 00:00:00 +0200http://www.hist-geo-space-sci.net/2/81/2011/<b>"Between unmanned and manned space research" Dr. Siegfried J. Bauer for his 80th birthday</b><br /><br />History of Geo- and Space Sciences, 2, 81-82, 2011<br /><br />Author(s): G. K. Hartmann<br /><br />No abstract available.Wed, 29 Jun 2011 00:00:00 +0200