Astronomical Positions Research Articles

Antikythera mystery

Robert P Crease meets inventor-financier-explorer Michael Dubno, who – from his Manhattan basement – is trying to solve the mystery of the Antikythera mechanical device, used by ancient Greeks to predict astronomical positions.

ANAMOLY IN ‘MUHURTA TIME’ OF TIRUMALA VENKATESWARA SWĀMIVĀRI BRAHMOTSAVAM

The starting time or commencement of , an annual festival, at the Lord Venkateswara Temple at , celebrated by (TTD) is a total deviation from injunction whereas an additional festival celebrated in an once in three years comes unaware in total conformity with prescription of the ‘ time” for the commencement of this most sacred and important temple ritual. The rectification of the deviation occurring due to the erroneous astronomical positions of planets, the Sun and the Moon, in the Luni-Solar Indian almanac (TTD ) is discussed here with a suggestion of rectification of in the “ Time” for the of the Planet and all life living on it.

On the Issue of Using “Useful” Tasks for Proof of Works in Blockchain

This paper is a logical continuation of the paper about possible approaches to solving the “Useful Proof-of-work for blockchains” problem. We suggest some alternative ways for searching useful tasks for Proof-of-work systems. These ways are based on the process of the multiple and independent repetition of a simple experiment. The experiment is to chose an element independently and uniformly from a quite large set and then to check if the chosen element has a specific rare property. In the classic blockchain of Bitcoin this experiment is a so-called hash-puzzle. In these terms the process of solving a hash-puzzle may be replaced by searching rare astronomical objects or Go positions with specific conditions. Moreover, we describe a possible attack on the blockchain systems in which the task instance generation algorithm is replaced by the algorithm of selecting the task instance from the existing database with public access for publication of task instances and discuss the way of protection.

GEOGRAPHICAL LOCATION OF SILLĀ IN MUSLIM ASTRONOMICAL LITERATURE OF THE THIRTEENTH TO SIXTEENTH CENTURIES CE

The Muslim world has been learning about Korea for a long time. Historical evidence shows that some of this knowledge predates the Islamic era; indeed, Iranian merchants have nurtured ties since the era of the Sillā dynasty (57 BCE–935 CE). For centuries after the house’s fall, the name stuck: References to Korea as Sillā, Shillā, and Basillā appear in Iranian historical and literary texts until the sixteenth century. By the thirteenth century, however, as Sino-Iranian connections grew, Muslims began to adopt a new name, Kao-li or Korea. Still, astronomers and geographers continued to use the name Sillā, as evidenced in astronomical texts written in the eleventh, thirteenth, and sixteenth centuries. In the fourteenth century, an interesting change in the evolution of the word Sillā occurred: Islamic ephemerides, diaries that chronicle astronomical positions, began to record the name Sillā in the same location along an eastern prime meridian as the toponym Kangdez. The origins of Kangdez—for example, whether it developed from an Iranian or Indian tradition—is unclear. Nonetheless, this widely used dual naming of a single geographical location persisted in Islamic astronomical texts into the sixteenth century. This article traces the transfer of geographical knowledge about Sillā and Kangdez into and throughout the Muslim world through the works of five generations of well-known Muslim astronomers, with a focus on their lesser-known works. It seeks to specify the manner in which astronomical knowledge about the location of Sillā and Kangdez circulated among Muslims from the thirteenth to sixteenth centuries.

The Balkans on the geographical maps of Claudius Ptolemy

The paper deals with the historical-geographical analysis of Ptolemy's maps known as Table V and Table IX. The maps were found in the "Urbinas Manuscript" of Ptolemy's work "Geography", which originated in the first half of the 2nd century AD, so it is accepted that the maps are from that period also. On the Fifth Map the western part of the Balkan Peninsula was presented, and on the Ninth Map the area of the eastern part of the Balkan Peninsula, in the pre-Roman and early Roman era. On maps and in the text, which serves as an explanation of the maps, there are plenty of data from topography and ethnography, and astronomical positions for more places. The data on the maps are not always consistent with the information in the text. Although there are also false geographical representations, these maps were ahead of their time in terms of cartographic methodology, geographical precision and toponomy. For over a millennium, this Ptolemy's work was lost and unknown in Europe, and when it was found in the 15th century, it significantly affected the Renaissance of geography and cartography, and the Renaissance of scientific thought in general. In this paper, the author deals with features and content analysis and identification of toponyms that have been presented on these maps, which have been aged more than two thousand years.

Ptolemy's heritage: The atlas as an ordering device

ABSTRACTWith his geography manual Geographia, Claudius Ptolemy not only produced the first atlas as a systematic map coverage of the known world but through his introduction of coordinate pairs for topographical objects, both rendered in these maps and in lists – thus producing the first gazetteer – he also provided the tools for georeferencing, and thus for ordering geospatial data. He was able to produce this gazetteer through his compilation work, matching distances between towns from travel reports with the few known astronomical positions. The article describes how in the sixteenth-century Netherlands this Ptolemaic legacy was gradually mastered, first through editing Greek and Latin editions of Ptolemy's geography manual, reconstructing and publishing his maps, producing concordances between the names in Ptolemy's gazetteer and modern names, and finally by substituting Ptolemy's mapping of the known world in antiquity by an updated version, culminated in Mercator's atlas , which, however, conceptually did not surpass its model.

Airy and positional astronomy

Sir George Airy (18011891), the seventh Astronomer Royal, made major contributions in numerous fields including many not directly concerned with astronomy. Throughout his life, however, he had a deep interest in fundamental aspects of astronomy, and constantly endeavoured to improve the instrumentation and procedures used for the measurement of astronomical positions. His principal achievements in this field were the refinement of techniques for the mathematical reduction of positional observations and their timely publication, and the design of a new generation of positional instruments which revitalized the work of the Royal Observatory at Greenwich, and proved to be influential for the next hundred years.

Sensitivity of paleoclimate simulation results to season definitions

According to the Milankovitch theory, slow variations of the Earth's orbital parameters change the amplitude of the seasonal cycle of insolation and are considered to be the main forcing mechanism of glacial‐interglacial cycles. Because of the precession and changes in eccentricity the length of seasons also varies. No absolute phasing is then possible between the insolation curves of two different periods. Various solutions to compare different periods have been given either for astronomical computations [e.g., Berger and Loutre, 1991; Laskar et al., 1993] or for model simulations [e.g., Kutzbach and Otto‐Bliesner, 1982; Mitchell et al., 1988], but the sensitivity of model results to the different possible solutions has never been quantified. Our results, based on simulations of the last interglacial climate, 126 kyr B.P., where changes in the length of the seasons are large, clearly show that phase leads or lags between the various solutions used introduce biases in the analysis of insolation and climate change of the same order of magnitude as the Milankovitch forcing. Our main conclusions are that (1) when comparing various model simulations, the date of the vernal equinox (i.e., the phasing of the seasonal cycle of insolation) as well as the definition of seasons must be the same for all models in order to avoid artificial differences; (2) seasons based on astronomical positions are preferred to seasons defined with the same lengths as today, since they better account for the phasing of insolation curves. However, insolation is not the only forcing in most atmospheric general circulation model simulations. We also discuss the impact of the calendar hidden behind the definition of the seasonal cycle of the other boundary conditions, such as sea ice or sea surface temperatures.

THE HEIGHT OF MOUNT EVEREST

Mount Everest, the world's highest peak, was discovered by geodetic survey. Before the observations and computations of the Survey of India it was unknown, lying hidden amongst the hundreds of high snow peaks of the great Himalayas. It is well worth recalling the story of its discovery in 1852, and the publication of that enigmatic figure of 29 002 ft. for its height. It was known that this figure was in error, but for nearly a century, scientific and practical difficulties prevented a better determination. The modern era began for Everest in the 1950's, when the Survey of India carried triangulation through Nepal and close to the mountain. Gravity and astronomical positions were used, the theoretical basis was improved, and the new figure of 29 028 ft. appeared to solve the problem of the accurate height of the peak (Gulatee, 1954). But in 1975 a new survey was brought in from the north, approaching much closer to the peak. Comprehensive field observations were taken and the theoretical approach was further improved. The height of the “Qomolangma Feng” as determined by the Chinese combined mountaineering and surveying expedition of 1975 was 8848·13±0·35 m (29 029·3±1·1 ft.) (Dansheng, 1979; Chen, 1980).

THE HEIGHT OF MOUNT EVEREST

Abstract Mount Everest, the world's highest peak, was discovered by geodetic survey. Before the observations and computations of the Survey of India it was unknown, lying hidden amongst the hundreds of high snow peaks of the great Himalayas. It is well worth recalling the story of its discovery in 1852, and the publication of that enigmatic figure of 29 002 ft. for its height. It was known that this figure was in error, but for nearly a century, scientific and practical difficulties prevented a better determination. The modern era began for Everest in the 1950's, when the Survey of India carried triangulation through Nepal and close to the mountain. Gravity and astronomical positions were used, the theoretical basis was improved, and the new figure of 29 028 ft. appeared to solve the problem of the accurate height of the peak (Gulatee, 1954). But in 1975 a new survey was brought in from the north, approaching much closer to the peak. Comprehensive field observations were taken and the theoretical approach...

Regional gravity studies of western and central Montana

During the summer and fall of 1963 a U.S. Air Force geodetic survey team of the 1381st (now the 1st) Geodetic Survey Squadron, under the supervision and direction of the author, conducted a regional gravity survey in western and central Montana. This survey established 2700 gravity stations and an associated base station network in the general area outlined from 106°W to 115°W and from 45°N to 49°N. The principal objectives of this work were to determine the feasibility of using combined geodetic and gravity data to evaluate gravimetric interpolation of astro‐geodetic deflections of the vertical and to determine the accuracy of astronomical positions corrected for gravimetrically interpolated astro‐geodetic deflections of the vertical [Anthony, 1964]. The data were later released to the author for geological interpretation.

Crustal Movements Detected by Geodetic Measurements

Geological researches revealed vertical crustal movements of several thousand meters and horizontal movements of tens of km in comparatively recent geological time such as the last 10-20 million years by faulting, bending, folding or overthrusting. Such changes as may now be in progress are considered to be detected and measured by geodetic means. However, the actual rates of changes per year are extremely small, and since it was doubtful that the conventional geodetic surveys may contribute much to clarify the tectonic movements in a reasonable period of years.Of geodetic surveys, precise levelling have, in principle, remarkable high precision (better than 1×10-6) and contributed till now to the detectians of features of crustal deformations accompanied by large earthquakes. However, we have yet only insufficient data to trace the progressing tectonic activities, because the time intervals between successive resurveys were too long (20-30 years). Recently, under the Project of Earthquake Prediction, the Geographical Survey Institute has started to repeat precise levelling along the first order levelling routes all over the land of Japan every five years. It is expected that such works may be able to reveal the details of tectonic deformations and accumulation of strain in the land of Japan.The precision of horizontal positionings by conventional precise triangulations is far inferior to that of precise levelling. It is estimated to be somewhat better than 1×10-5. If horizontal deformations are assumed to be of the order of 10-7 per year, this means that one century or more years are necessary to trace the movements. This might be the reason why reliable records were not obtained by triangulation except when sudden destructions were caused by large earthquakes as in Japan and California. Recently, the accuracy of distance measurement with an electrooptical instrument (such as Geodimeter) has attained to about 1×10-6, and we have now the back ground of detecting and tracing the horizontal deformations in a reasonably short period (say, in several tens of years).The direct evidence of the theory of continental drift may be provided by changes in astronomical positions, but it was unfortunate the suggested rapid changes are in longitude. Until very recently, the reliability of longitude observation was not sufficient owing to the inaccuracies of observing instruments and the inaccurate corrections to the time of propagation of wireless time signals. Now, the standard time signals (UTC) in the world are synchronized in the accuracy of better than 1ms (=1/1000sec), and high precision instruments (PZT and precise astrolabe) have also been developed. Relative movements of continents of the order of several cm per year may be detected in the near future. Furthermore, artificial satellites have become promising means of connecting geodetic nets in accurate and pure three dimentional geometrical ways.In conclusion, although conventional geodetic survey did not contribute so much until recently, we may expect in near future newly developed geodetic means will afford useful data which clarify the tectonic movements of the crust and reveal the internal activities of the earth.

Great Earthquakes and the Astronomical Positions of Uranus

THANKS to the excellent collection of uniform data of earthquakes given by Gutenberg and Richter1, it is now easily possible to study statistically the influence of different factors on earthquakes. In the course of a study of tidal effects on earthquakes2, the astronomical positions of the planets have also been taken into account and a remarkable correlation between the positions of Uranus and the moment of great earthquakes has been established for a certain period. Gutenberg and Richter's data of all earthquakes equal or greater than magnitude 7¾ have been used. The investigations will be published in detail later, but here attention is directed to the results concerning the position of Uranus.

The Old Iranian Calendars Again

Most Iranists are probably acquainted with some of my writings on Iranian chronology and systems of time-reckoning. One of the essential points in my outline of the history of the Iranian calendars is the theory I put forward about the date of the creation of a fixed religious year, co-existing and running parallel with the civil year, which was a vague one. This fixed year, called in Pahlavi literature Vihēǰakīk, was, however, theoretical and without any application in daily life. It was used only by the Zoroastrian clergy for the purpose of ascertaining the original position of the religious festivals and keeping them in or about their astronomical positions. By the ‘original position’ is meant the places these most important religious days occupied in the tropical year at the time of instituting the Vihēǰakīk year, which time may or may not have been the epoch of the initial adoption of the Mazdayasnian or ‘Young Avestan’ civil year in Iran. The date I proposed was 441 B.c., or at any rate some time in the first decade of the second half of the 5th century B.c.

Variation of the compass south of Franz Joseph Land

When navigating northwest of Novaya Zemlya and south of Franz Joseph Land the masters of sealing‐ vessels do not correct their courses for variation of compass, as it is said that their dead‐reckoning will be erroneous by the amount of variation corrected for.On the motor‐cutter Björnöy, when proceeding from Admiralty Peninsula to 77° 30′ north, 59° 00′ east, thence to 78° 30′ north, 45° 00′ east, and thence to 77° 50′ north, 40° 0′ east, no correction for variation was used, and the courses laid down agreed well with astronomical positions.

Societies and Academies

Societies and Academies

Captain Cook's Accuracy

IN NATURE, vol. xix. p. 408, there is an article entitled “Captain Cook's Accuracy,” which I think reflects unjustly upon the late Admiral Wilkes, U.S.N. As a specimen of Wilkes's inaccuracy the writer of the article cites first the discrepancy in the position of Turtle Island, the south-easternmost of the Fiji group, Cook and Wilkes differing more than 30′ of longitude. The narrative of the U.S. Exploring Expedition was written on board ship during the progress of the work, and was placed by Wilkes in the hands of the printer immediately upon his return, in order that the general results might be known without delay. The astronomical positions were given as they were recorded at the time, and were not corrected for final chronometric errors and rates, which were carefully ascertained while the charts were being prepared for publication. A comparison of the narrative with the atlas, published subsequently, will exhibit differences of longitude almost throughout.

Astronomical Positions in European Turkey, Mount Caucasus, and Asia Minor, Fixed

Astronomical Positions in European Turkey, Mount Caucasus, and Asia Minor, Fixed