Narrow band near infrared images of comet 1995 O1 (Hale-Bopp), where obtained in day-time, during April 1997, using the 1.52m Carlos Sanchez Telescope, at Teide Observatory (Tenerife, Spain), by the Comet Hale Bopp European Team. The comet was observed continuously for up to 11 hours hours each day on a total of 15 days. This allows us to obtain a

En el presente trabajo se muestra que el retorcimiento de las líneas del campo magnético, la flotación diferencial y la dinámica de vórtices son ingredientes fundamentales de la física que gobierna el ascenso de tubos de flujo magnético flotantes a través de la zona de convección solar. Con este fín se considera un tubo magnético horizontal de

Recently, huge photometric databases are being obtained for the Magellanic Clouds and other Local Group galaxies. These data allow, not only to study in great detail the star formation history of these systems, but also provide important information on details of stellar evolution theory. In the case of the LMC, two structures not previously

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The system SBS 0909+532A, B is a double consisting of a quasar and a fainter component that was, until now, spectroscopically unresolved. Spectra taken in good seeing conditions ( {FWHM}=1^{''} ) with the 4.2 m William Herschel Telescope separate the A and B components, showing that both are quasars with the same redshift, z=1.377 , and identical

We report on the latest inferences concerning solar differential rotation that have been drawn from the helioseismic data that are now available from the Solar Oscillations Investigation (SOI) using the Michelson Doppler Imager (MDI) on the Solar and Heliospheric Observatory (SOHO). That spacecraft is positioned in a halo orbit near the Sun-Earth