Adaptive Optics Comparison

Remarkable details in the core of the globular cluster M-13 are revealed in a new image obtained with the Gemini Observatory's new Altair adaptive optics system at the Frederick C. Gillett Telescope (Gemini North) on Hawaii's Mauna Kea. The razor-sharp Gemini image is shown in the upper right of the above sequence that also includes a wide-field view of the cluster (and blow-up of the core) as imaged by the Canada-France-Hawai`i Telescope also on Mauna Kea. Below the Gemini adaptive optics image is another image for comparison that shows the same field without adaptive optics on Gemini. This non-adaptive optics image was obtained under exceptional conditions with an average "seeing" of 0.26 arcseconds (full-width half-max). Both Gemini images were obtained in the near-infrared in the H-band at a wavelength of 1.65 microns using the Gemini Near-Infrared Imager (NIRI). The images were both obtained from a stack of 18, 30-second integrations obtained on May 10, 2003. The resolution of the Altair image is 60 milli-arcseconds, which is within about 20 milli-arcseconds of the theoretical limit of the 8-meter Gemini telescopes observing in the H-band. The image has a field of view of 20 arcseconds. All images were obtained as part of ongoing commissioning work with Altair on the Gemini North Telescope with special thanks to the Altair commissioning team members from the Canadian National Research Council/Herzberg Institute of Astrophysics.