Related papers: Estimation of the Eclipse Solar Radius by Flash Sp…

Observations of HZ Her/Her X-1 by the Rossi X-ray Timing Explorer (RXTE) covering high state eclipses of the neutron star are analyzed here. Models of the eclipse are used to measure the radius and atmospheric scale height of HZ Her, the…

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…

The Kodaikanal Archive Program (India) is now available to the scientific community in digital form as daily digitized solar white light pictures, from 1923 to 2011. We present here the solar radius data, obtained after a painstaking effort…

We present an analysis of the X-ray light curves of the magnetic cataclysmic variable DP Leo using recently performed XMM-Newton EPIC and archival ROSAT PSPC observations. We determine the eclipse length at X-ray wavelengths to be 235 +-5…

The propagation direction and true velocity of a solar coronal mass ejection, which are among the most decisive factors for its geo-effectiveness, are difficult to determine through single-perspective imaging observations. Here we show that…

A model based on celestial geometry and atmospheric physics predicts the dimming and the color of lunar eclipses. Corresponding visual magnitudes and color indices for eclipses from year 2000 through 2050 are listed. The enlargement of the…

Computed color indices and spectral shapes for individual stars are routinely compared with observations for essentially all spectral types, but absolute fluxes are rarely tested. We can confront observed irradiances with the predictions…

We present new V-band differential photometry and radial-velocity measurements of the unevolved 1.18-day period F+G-type double-lined eclipsing binary VZ Cep. We determine accurate values for the absolute masses, radii, and effective…

We carried out observations of the small jovian satellite Amalthea (J5) as it was being eclipsed by the Galilean satellites near the 2009 equinox of Jupiter in order to apply the technique of mutual event photometry to the astrometric…

Solar eclipses provide an excellent opportunity to study the effects of a sudden localized change in photoionization flux in the Earth's ionosphere and its consequent repercussion in the Geomagnetic field. We have focused on a subset of the…

The partial lunar eclipse of July 16, 2019, left the lower part of the Moon illuminated at its maximum phase in Padova (Italy). Occulting it behind far buildings it was possible to compare the light of Jupiter and Saturn de-focused to the…

The primary objective of this paper is to construct an analytical model for determining the total duration of eclipse events of satellites. The approach assumes that the trace formed in the orbital plane, cutting body shadow under the…

We present some new accurate CCD photometry analysis of the white light solar corona at the time of the last 20 March 2015 total eclipse (airborne observations on a Falcon 7X and at ground-based Svalbard). We measured coronal brightness…

A rare eclipse of the mysterious object Epsilon Aurigae will occur in 2009-2011. We report an updated single-lined spectroscopic solution for the orbit of the primary star based on 20 years of monitoring at the CfA, combined with historical…

We report air temperature and humidity changes during the two solar eclipses of 26 December 2019, and of 21 June 2020, respectively, in the cities of Al-Hofuf and Riyadh in Saudi Arabia. During the December eclipse the Sun rose already…

Low-mass stars in eclipsing binary systems show radii larger and effective temperatures lower than theoretical stellar models predict for isolated stars with the same masses. Eclipsing binaries with low-mass components are hard to find due…

Some 8000 images obtained with the SECIS fast-frame CCD camera instrument located at Lusaka, Zambia, during the total eclipse of 21 June 2001 have been analyzed to search for short-period oscillations in intensity that could be a signature…

Solar eclipse is an unique opportunity to study the lower ionospheric variabilities under a controlled perturbation when the solar ultraviolet and X-ray are temporally occulted by the lunar disk. Sub-ionospheric Very Low Frequency (VLF)…

Luminosity, which is the total amount of radiant energy emitted by an object, is one of the most critical quantities in astrophysics for characterizing stars. Equally important is the temporal evolution of a star's luminosity because of its…

The last solar minimum has been unusually quiet compared to the previous minima (since space-based radiometric measurements are available). The Sun's magnetic flux was substantially lower during this minimum. Some studies also show that the…