A key instrument for an Extremely Large Telescope (ELT) is likely to be multi-object spectrometer which observes at least 100 discrete sources with diffraction limited spatial resolution and moderate spectral resolution in the wavelength region from 1.0 to 2.5 μm. Such an instrument has been chosen as the principal driver for the Smart Focal Planes

We report the onset of a large amplitude, statistically significant periodicity (~46 d) in the Rossi X-ray Timing Explorer/All Sky Monitor (RXTE/ASM) data of the prototype X-ray burster 4U 1636-53, the X-ray flux of which has been gradually declining over the last 4 yr. This behaviour is remarkably similar to that observed in the neutron star low

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The Hanle depolarization signals of Sr i λ4607 Å have been used to estimate the unsigned magnetic flux and magnetic energy existing in the quiet Sun photosphere. However, the Sr i λ4607 Å Hanle signals are not sensitive to the unsigned flux and energy. They only bear information on the fraction of photosphere occupied by magnetic field strengths

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