Descriptions of eleven aurorae observed in the Canary Islands during the period 1770 - 2010 have been found in different documents. Most of them are coincident with periods of strong solar activity, with the geomagnetic latitude playing a minor role. Coronal mass ejections are the most probable solar source of these low-latitude events. The absence

Jovian X-rays can be broadly classified into two categories: (1) "auroral" emission, which is confined to high-latitudes ( ˜>60° ) at both polar regions, and (2) "dayglow" emission, which originates from the sunlit low-latitude ( ˜

Two data series of disk integrated solar irradiance, taken by the Variability of the solar IRradiance and Gravity Oscillations (VIRGO) experiment on board the Solar and Heliospheric Observatory (SoHO) mission, corresponding to epochs of minimum and maximum solar activity have been analysed in order to study the background signal of the associated

Using GOLF/SOHO data a detailed analysis of the solar background spectrum has been performed at high and low phases of solar activity cycle. The analysis includes not only the non-periodic components of the background power spectrum but also the periodic ones. Apart from the solar activity, other causes produce similar effects in the data

Non-axisymmetric features such as bars drive the dynamical and secular evolution of disk galaxies by exerting gravitational torques which redistribute mass and angular momentum. While most (> 70 %) spirals are barred in the local Universe, early studies of the Hubble Deep Field (HDF) suggest a remarkably low bar fraction ( 20 %) at intermediate

We use the OSUBSGS (Ohio State University Bright Spiral Galaxy Survey, Eskridge et al. 2002) and NIRS0S (Near-IR S0 Survey, Laurikainen et al. 2005) data to study the connection of bars and outer spiral structures. Using near-IR images, the non-axisymmetric gravity perturbation associated with the bar is evaluated at various distances outside the