相关论文: Variable Earth's Rotation Speed in the 14th to 16t…
Historical records of total solar eclipses provide vital information for computing the rotation of the Earth and understanding its long-term variations by providing data from the time before the modern measurements. While eclipses recorded…
We investigate the anomalies in the Earth - Moon system using ancient eclipse data. We identify nine groups of anomalous eclipses between 400 and 1800 AD recorded in parts of India that should have completely missed the subcontinent as per…
Excursions in the carbon-14 record measured in tree rings are attributed to various high energy but short-lived cosmic effects. So far, rapid changes at 774-775 CE, 993-994 CE and 660 BCE have been convincingly interpreted as due to rapid…
We analyze the near-surface air temperature response, at three different heights over the ground, recorded by the Williams College expedition under meteorological conditions characterized by cloudy skies during the longest total solar…
This article reviews atmospheric changes associated with 44 solar eclipses, beginning with the first quantitative results available, from 1834 (earlier qualitative, accounts also exist). Eclipse meteorology attracted relatively few…
The power spectral analyses of the Sun's surface equatorial rotation rate determined from the Mt. Wilson daily Doppler velocity measurements during the period 3 December 1985 to 5 March 2007 suggests the existence of 7.6 year, 2.8 year,…
Records of observations of sunspots and auroras in pre-telescopic historical documents provide useful information about past solar activity both in long-term trends and short-term space weather events. In this study, we present the results…
The daily sunspot numbers of the whole disk as well as the northern and southern hemispheres from January 1, 1945 to December 31, 2010 are used to investigate the temporal variation of the rotational cycle length through the continuous…
We examine in detail 15 Babylonian observations of lunar appulses and occultations made between 80 and 419 BC for the purpose of setting useful limits on Earth's clock error, as quantified by $\Delta$T, the difference between Terrestrial…
We present an X-ray eclipse timing analysis of the transient low mass X-ray binary XTE J1710-281. We report observations of 57 complete X-ray eclipses, made with the proportional counter array detectors aboard the RXTE satellite. Using the…
We report the empirical detection of a multi-planet quasi-commensurability in the Solar System and identify an anomalous exclusion that may bear on the dynamical history of Uranus. An exhaustive search identifies T* = 420,403 days (approx.…
Paleoclimate records provide a critical long-term perspective on natural climate variability, essential for understanding contemporary climate change. However, existing paleoclimate proxies lack the spatial-temporal coverage for studying…
With an aim to examine how much information of solar rotation can be obtained purely spectroscopically by observing the sun-as-a-star during the 2012 May 21 eclipse at Okayama Astrophysical Observatory, we studied the variation of radial…
We have detected several periodicities in the solar equatorial rotation rate of sunspot groups in the Greenwich Photoheliographic Results (GPR) during the period 1931-1976, the Solar Optical Observing Network (SOON) during the period…
Duration and period of transits in extrasolar planetary systems can exhibit long-term variations for a variety of reasons. Here we investigate how systemic proper motion, which steadily re-orients planetary orbit with respect to our line of…
Solar irradiance variations across various timescales, from minutes to centuries, represents a potential natural driver of past regional and global climate cold phases. To accurately assess the Sun's effect on climate, particularly during…
Rotation is a prominent feature of the Sun, and it plays a crucial role in the generation and dynamic evolution of solar magnetic fields. The daily composite time series of Ca II K plage areas from 1907 February 1 to 2023 December 31 is…
In a classic 1982 paper in this journal, Jean Meeus used a statistical approach for finding the mean frequency of a total and an annular eclipse of the Sun at a given place on the surface of the Earth. In this current paper we tackle the…
The length of the solar activity cycle fluctuates considerably. The temporal evolution of the corresponding cycle phase, that is, the deviation of the epochs of activity minima or maxima from strict periodicity, provides relevant…
The variable Sun is the most likely candidate for natural forcing of past climate change on time scales of 50 to 1000 years. Evidence for this understanding is that the terrestrial climate correlates positively with solar activity. During…