Related papers: The Mayan Long Count Calendar
The Long Now Foundation is building a mechanical clock that is designed to keep time for the next 10,000 years. The clock maintains its long-term accuracy by synchronizing to the Sun. The 10,000-Year Clock keeps track of five different…
The equation of time is fundamental for calculating the rising and setting times of the Sun. The concepts of sidereal and solar day and locak noon, we show how the length of the day depends on solar declination and Earth's orbit position,…
Context. Solar activity, dominated by the 11-year cyclic evolution, has been observed directly since 1610. Before that, indirect cosmogenic proxy data are used to reconstruct it over millennia. Recently, the precision of radiocarbon…
Using Mach's principle, we will show that the observed diurnal and annual motion of the Earth can just as well be accounted as the diurnal rotation and annual revolution of the Universe around the fixed and centered Earth. This can be…
Through meticulous daily observation of the Sun's large-scale magnetic field the Wilcox Solar Observatory (WSO) has catalogued two magnetic (Hale) cycles of solar activity. Those two (~22-year long) Hale cycles have yielded four…
Sophisticated computation methods were developed 4000 years ago in Mesopotamia in the context of scribal schools. The basics of the computation can be detected in clay tablets written by young students educated in these scribal schools. At…
The so-called Miccinelli documents are a set of documents which were written by Jesuit scholars in Peru within the first half of the 17th century. Among such documents, one contains the depiction of a Quipu, that is, a device made out of…
In an effort to determine accurate orbital and physical properties of a large number of bright stars, a method was developed to fit simultaneously stellar parameters (masses, luminosities, effective temperatures), distance, and orbits to…
We outline the priority of high quality data of astronomical content as our strategy for the analysis of the ancient astronomical records in the search of the absolute chronology of the Near East in II millennium BC. The correspondingly…
Bayesian statistics and Markov Chain Monte Carlo (MCMC) algorithms have found their place in the field of Cosmology. They have become important mathematical and numerical tools, especially in parameter estimation and model comparison. In…
It has been known for over three decades that the monochromatic X-ray and UV luminosities in quasars are correlated, though non-linearly. This offers the possibility of using high-z quasars as standard candles for cosmological testing. In…
This illustrated article represents a popular account of the study of the Babylonian astronomical records of Enuma Anu Enlil tablet series i.e. of the Venus Tablet of Ammisaduqa and of two lunar eclipses linked with the IIIrd dynasty of Ur,…
It is widely believed that the advance of science in the Islamic world after the mid-fifteenth century A.D. suffered a decline. For the purpose of examining this belief, a manuscript by Qasim ali al-Qayini (ca. A.D.1685) was chosen based on…
Various methods (or recipes) have been proposed to predict future solar activity levels - with mixed success. Among these, some precursor methods based upon quantities determined around or a few years before solar minimum have provided…
The McNish and Lincoln (ML) method, introduced in 1949, was one of the first attempts to produce mid-term forecasts of solar activity, up to 12 months ahead. However, it has been poorly described and evaluated in the past literature, in…
One of main events on Rapanui before the cruel war (several wars) between the Hanau Momoko and Hanau Eepe was the annual election of the bird-man. Plainly, the local priest-astronomers, the descendants of immigrants from the Andean region…
One of the main difficulties that students have in learning astronomy topics is that they fail to relate theoretical information with what they experience in the world around them. The construction by students of a conceptual framework in…
The Euahlayi people are an Australian Aboriginal language group located in north-central New South Wales and south-central Queensland. They have a rich culture of astronomy, and use of the night sky in resource management. Like several…
Between the mid-eighteenth and mid-nineteenth centuries, long-haul oceanic voyages of exploration and discovery routinely carried astronomical tent observatories to support land-based longitude determinations using heavy and cumbersome…
For a hypothetical planet on a highly eccentric orbit, we have calculated the osculating orbital parameters and its closest approaches to Earth and Moon over a period of 750 kyr. The approaches which are close enough to influence the…