By making use of real information about the continental and oceanic surface distribution of the Earth, and cloudiness data from the International Satellite Cloud Climatology Project (ISCCP), we have studied the large-scale cloudiness behavior according to latitude and surface types (ice, water, vegetation and desert). These empirical relationships

Observations of the Earth as a planet using the earthshine technique (i.e. looking at the light reflected from the dark side of the Moon) have been used for climate and astrobiology studies. They provide information about the planetary albedo, a fundamental parameter of the Earth's energy balance. Here we present, for the first time, observations

On June 30, 1973, Concorde 001 intercepted the path of a solar eclipse over North Africa, Flying at Mach 2.05 the aircraft provided seven observers from France, Britain and the United States with 74 min of totality bounded by extended second (7 min) and third (12 min) contacts. The former permitted searches for time variations of much longer period

After four years during which only the spectacular light echo was showing continuous and rapid evolution while the central star was nearly constant, in autumn 2006 V838 Mon began a sequence of events which profoundly altered its spectroscopic and photometric behavior: (a) an eclipse of the B3V companion, characterized by the disappearance and

Theoretical studies of the normal modes of a coronal slab often neglect gravity, as in Edwin and Roberts ( Solar Phys. 71, 239, 1982). Here we study analytically the effect of gravity acting on a horizontal slab as a first step away from a homogeneous medium. Because of the inclusion of gravity, the symmetry of a homogeneous slab is lost, so the

The neutrino production rate strongly depends on the temperature, and a small variation of chemical composition in the central regions can imply a large variation of neutrino flux. For some values of their frequencies and wavenumbers, the internal waves e xcited at the bottom of the solar convective zone are able to propagate until the central