Related papers: The solar eclipse of August 30, 1905 at Alcala de …
The relationship between cosmic ray intensity decreases and solar events is still an open field of space research. In this work a complete study of solar events occurred from January 2003 to December 2005, is considered. This three-years…
We have observed evidence for $p$-mode oscillations in the G0 IV star etaBoo (V = 2.68). This represents the first clear evidence of solar-like oscillations in a star other than the Sun. We used a new technique which measures fluctuations…
Eclipses in the 14.4-day period double-lined binary SS Lac were observed photographically and visually early in the 20th century, but stopped some 50 or 60 years ago. This has been explained by the presence of a distant third star in the…
We investigate periodicities in mean heliographic latitudes of sunspot groups, called active latitudes, for the last six complete solar cycles (1945-2008). For this purpose, the Multi Taper Method and Morlet Wavelet analysis methods were…
This white paper is a call for a concerted effort to support total solar eclipse observations over the next decade, in particular for the 21 August 2017 eclipse which will traverse the US continent. With the recent advances in image…
Solar-like oscillations are excited in cool stars with convective envelopes and provide a powerful tool to constrain fundamental stellar properties and interior physics. We provide a brief history of the detection of solar-like…
Coronal jets, which extend from the solar surface to beyond 2 $R_\odot$, were observed in the polar coronal hole regions during the total solar eclipse on 2017 August 21. In a time-series of white-light images of the corona spanning 70…
It is shown that the Sun can become partially transparent to high energy photons in the presence of a pseudo-scalar. In particular, if the axion interpretation of the PVLAS result were true then up to 2% of GeV energy gamma rays might pass…
With the same general purposes as Part I of this monograph, we analyze here major events in the history of the Earth, such as the formation of the Earth itself, the origin of life, the great glaciations and the mass extinctions of species,…
The Pic du Midi Observatory, situated at an altitude of 2890 meters, was always very hard to reach, and living there was difficult. Its history is a lesson in courage. It is also a lesson in creativity, because astronomers took advantage of…
The effects of the solar eclipse of March 20, 2015 on different ionospheric layers were studied, using vertical ionospheric soundings from the ionosondes of Rome (41.8N, 12.5E), Gibilmanna (37.9N, 14.0E), and San Vito dei Normanni (40.6N,…
A re-investigation of the parapegma of Euktemon (5th century BC, Athens), based on the assumption that some star observations may in fact have been calculated rather than directly observed. The calculation follows Pliny, Natural History…
The diameter of the Sun has been measured using Baily's beads during central eclipses, observed with portable telescopes. A blend of tiny emission lines produced in the first several hundred kilometers above the photosphere gives a light…
High quality observations of the low degree p-modes exist for almost two complete solar cycles using the solar spectrophotometer Mark-I, located and operating at the Observatorio del Teide (Tenerife, Spain). In this work, the observations…
This thesis assesses the influence of astronomical phenomena on the Earth's biosphere and climate. I examine in particular the relevance of both the path of the Sun through the Galaxy and the evolution of the Earth's orbital parameters in…
The 1703 was the first year of full operation of the meridian line in the Basilica of St. Maria degli Angeli in Rome. The instants of solstices and equinoxes, the \textit{Anni Cardines}, obtained by comparing transit timings of Sun and…
The sunlight reflected from the Moon during a total lunar eclipse has been transmitted through the Earth's atmosphere on the way to the Moon. The combination of multiple scattering and inhomogeneous atmospheric characteristics during that…
The measurement of the deflection of starlight during a total solar eclipse on May 29, 1919 was the first verification of general relativity by an external team of scientists, brought Einstein and his theory to the attention of the general…
The solar program of the Astronomical Observatory of Madrid started in 1876. For ten solar cycles, observations were made in this institution to determine sunspot numbers and areas. The program was completed in 1986. The resulting data have…
Among several methods for accurate measurements of solar diameter, there are transits at fixed almucantarat used in solar astrolabes. The almucantarat is a circle of given height. The horizon circle is the zero almucantarat, and data from…