The following images were obtained during the 2007-8 commissioning of the William Herschel Telescope's GLAS laser guide star with the adaptive-optics system NAOMI. A separate page shows images obtained with NAOMI using natural guide stars.

• 10th-mag star, H band
• M15 globular cluster, H band
• Uranus, H band
• Star wars

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Open- and closed-loop H-band images of a 10th-mag star. FWHM improved from 0.8 to 0.2 arcsec. The DIMM-MASS turbulence monitor showed that at the time of observing this star, much of the free-atmosphere turbulence arose in a layer at altitude ~ 4 km. Observed with GLAS/NAOMI/INGRID April 2008. Scale 0.04 arcsec/pixel.

Open-loop	Closed-loop

Open- and closed-loop (NGS + LGS) H-band images of part of the M15 globular cluster. The size of the field shown here is 6 arcsec x 5 arcsec. The AO-corrected FWHM is 0.16 arcsec, in natural seeing of 0.4 arcsec. Observed with GLAS/NAOMI/INGRID September 2007.

Open-loop	Closed-loop

Open- and closed-loop H-band images of part of Uranus. Observed with GLAS/NAOMI/INGRID September 2007.

Open-loop	Closed-loop

The GLAS laser beam can be seen at left in the image below, emerging from the dome of the William Herschel Telescope.

The unrelated beam at right (less powerful, but closer) was fired from a site close to the Nordic telescope, by a team from Oerlikon (Zurich). It's a visual reference for an accompanying IR laser beam (10 microW, wavelength 1 micron). The beams were usually fired horizontally, towards a receiver on Tenerife, 140 km away, with the aim of measuring the effects of scintillation in the IR. The aim is to demonstrate the feasibility of using an IR laser beam to transmit data from the ESA/NASA Mars Sample Return orbiter, back to earth. An IR laser provides a high bandwidth, useful e.g. for returning video of the docking between orbiter and returning lander.

This image was kindly provided by Thomas Dreischer of Oerlikon (September 2008).

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Last Updated by Chris Benn: 2008 Sep 26 GLAS comissioning team