Theoretical pulsation frequencies derived from a typical model computation are used to identify the periods during which the Delta Scuti star 63 Herculis...

Astronomical infrared spectral features at ~6.6, 9.8 and 20 micronm have recently been suggested as being due to the planar graphene form of C24 carbon cluster...

Recent observations and theoretical considerations have linked gamma-ray bursts with ultra-bright type Ibc supernovae (`hypernovae'). We here work out a...

We report on the detection of a third massive star component in the σ Orionis AB system, traditionally considered as a binary system. The system has been...

A three-dimensional equation for deriving the scattering properties per unit volume of interplanetary space is obtained. The equation is related to the zodiacal...

A large-scale three-dimensional model of Galactic extinction is presented based on the Galactic dust distribution model of citet{DS01}. The extinction AV to any...

We present the results of a set of three-dimensional numerical simulations of magnetic flux emergence from below the photosphere and into the corona. The corona...

We present a kinematical study of the optical ejecta of GK Per. It is based on proper-motion measurements of 282 knots from ~20 images spanning 25 years...

We report the detection of main-sequence and blue horizontal-branch stars of the Ursa Minor dwarf spheroidal galaxy beyond its tidal radius, indicating the...