The Gran Telescopio Canarias (GTC) primary mirror control system is responsible for making the 36 segments behave like a monolithic mirror. It deals with 108 positioners giving 3 degrees of freedom to each segment, 168 position sensors installed between adjacent segments measuring nanometrical displacements, 216 actuators controling the figure of

The GTC (Gran Telescopio Canarias) is an optical/IR telescope, with a 10,4 meter segmented primary, installed at the Observatorio del Roque de Los Muchachos (ORM), at La Palma. Past July 2007 it saw its First Light showing a very promising behaviour. The very good image quality achieved at that an early stage of telescope commissioning is a direct

NGC 1851 is surrounded by a stellar component that extends more than 10 times beyond the tidal radius. Although the nature of this stellar structure is not known, it has been suggested to be a sparse halo of stars or associated with a stellar stream. We analyse the nature of this intriguing stellar component surrounding NGC 1851 by investigating

The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy programme designed to map a set of nested fields totalling ˜380 deg2. Fields range in size from 0.01 to ˜20 deg2, using the Herschel-Spectral and Photometric Imaging Receiver (SPIRE) (at 250, 350 and 500 μm) and the Herschel-Photodetector Array Camera and Spectrometer (PACS) (at

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We describe the on-board electronics chain and the on-ground data processing pipeline that will operate on data from the Herschel-SPIRE photometer to produce calibrated astronomical products. Data from the three photometer arrays will be conditioned and digitised by on-board electronics and sent to the ground with no further on-board data