Related papers: V\'enus selon Ibn al-Shatir
We report on general relativistic calculations of quasiequilibrium configurations of binary neutron stars in circular orbits with zero vorticity. These configurations are expected to represent realistic situations as opposed to corotating…
We perform a post-Newtonian (PN) solar system analysis for Palatini $f(R)$ theories considering finite volume non-spherical planets and with emphasis to $f(R)$ functions that are analytical about $R=0$. First we consider the Will-Nordtvedt…
Venus and Earth are similar in bulk properties yet followed dramatically different climatic trajectories. Reconstructing Venus's climate evolution requires understanding how rotation, obliquity, eccentricity, and solar luminosity shaped…
Context: With the increasing knowledge of the terrestrial planets due to recent space probes it is possible to model their rotation with increasing accuracy. Despite that fact, an accurate determination of Venus precession and nutation is…
Solving Einstein's equations precisely for strong-field gravitational systems is essential to determining the full physics content of gravitational wave detections. Without these solutions it is not possible to infer precise values for…
This HDR-thesis is devoted to the study of the rotation of the natural satellites of the giant planets and of Mercury. These bodies have a resonant rotation. Most of the natural satellites rotate synchronously, showing the same hemisphere…
The sphericity of the form of the Earth was questioned around the year 1687, primarily, by Isaac Newton who deduced from his theory of universal gravitation that the Earth has the form of a spheroid flattened at the poles and elongated at…
The manuscript New Theory of Sunspots was identified and attributed to the Jesuit astronomer and hydrographer from Marseille Esprit Pezenas (1692-1776) during the year 2002, during the systematic search for papers concerning him in the…
Albert Einstein postulated the equivalence of energy and mass, developed the theory of special relativity, explained the photoelectric effect, and described Brownian motion in five papers, all published in 1905, 100 years ago. With these…
EGRET gamma-ray archival data used with GALPROP software show two ringlike structures in Milky Way Plane which roughly tally with distribution of stars ([1] & references therein). To understand fully the implications of this and similar…
By the twelfth century, northern European scholars gradually embraced Arabic innovations in science and technology. England naturally developed into a significant centre of the new learning in western Europe. Hereford, and specifically its…
We study models of uniformly and differentially rotating neutron stars in the framework of post-Newtonian approximation in general relativity as established by Chandrasechar. In particular, we adopt the polytropic equation of state in order…
A long-term numerical integration of the classical Newtonian approximation to the planetary orbital motions of the full Solar System (sun + 8 planets), spanning 20 Gyr, was performed. The results showed no severe instability arising over…
We introduce a convolution on a 2-sphere and use it to show that the linearised Becchi-Rouet-Stora-Tyutin transformations and gauge fixing conditions of Einstein-Hilbert gravity coupled to a two-form and a scalar field, follow from the…
The fields of occultation and microlensing are linked historically. Early this century, occultation of the Sun by the Moon allowed the apparent positions of background stars projected near the limb of the Sun to be measured and compared…
Russell (1948) famously described eclipses as the "royal road" to stellar astrophysics. From photometric and spectroscopic observations it is possible to measure the masses and radii (to 1% or better!), and thus surface gravities and mean…
During the first few centuries CE, the centre of the known world gradually shifted from Alexandria to Constantinople. Combined with a societal shift from pagan beliefs to Christian doctrines, Antiquity gave way to the Byzantine era. While…
The POLAR Investigation of the Sun (POLARIS) mission uses a combination of a gravity assist and solar sail propulsion to place a spacecraft in a 0.48 AU circular orbit around the Sun with an inclination of 75 degrees with respect to solar…
In this talk I will briefly outline work in progress in two different contexts in astrophysical relativity, i.e. the study of rotating star spacetimes and the problem of reliably extracting gravitational wave templates in numerical…
We consider the geometric Titius-Bode rule for the semimajor axes of planetary orbits. We derive an equivalent rule for the midpoints of the segments between consecutive orbits along the radial direction and we interpret it physically in…