Arches Cluster with AO

With more clarity than is possible even with the Hubble Space Telescope, this infrared image of the Arches Cluster is the sharpest image ever taken of this cluster, which is located less than 100 light years from the center of our galaxy. The cluster is so densely packed that 300,000 of its stars would fill the empty space between our sun and our nearest stellar neighbor Alpha Centauri, 4.3 light years away. Gemini's unique capabilities allowed the telescope on Hawaii's Mauna Kea to image this cluster at an unprecedented clarity. To do this Gemini used an adaptive optics system called Hokupa'a that was built by the University of Hawaii Institute for Astronomy Adaptive Optics Group and funded by the National Science Foundation. The image was taken in K' (2.1µm), the field is 22x19 arcsec, north is up and east is to the left. The image reveals very faint stars down to magnitude 20. The Arches Cluster is one of the largest clusters of stars in our galaxy and not very well understood due to the 25,000 light years of obscuring dust that lies between us and our galaxy's center. The cluster is about 10 times larger than most other clusters in our galaxy and is destined to be ripped apart by the intense gravitational influence of the nucleus of our galaxy.