A High Resolution View of the Heavily Obscured Globular Cluster Liller 1

Near-infrared image of the dense globular cluster, Liller 1, obtained with the GeMS adaptive optics system on the Gemini South telescope in Chile.

The extremely high densities of globular clusters are one of the few places where astronomers might observe the collision of stars, and new work shows that Liller 1 is one of the most extreme examples, hosting the second highest rate of potential stellar collisions of all stellar clusters. S. Saracino (Università di Bologna and Osservatorio Astronomico di Bologna, Italy) and collaborators have used the Gemini South Adaptive Optics Imager (GSAOI) and the Gemini Multi-conjugate Adaptive Optics System (GeMS) to provide an exceptionally detailed view of this globular cluster. It is located in the Galactic bulge and heavily obscured at visible wavelengths, though the closely-packed stars are evident in the near-infrared observations. The researchers produced the deepest and most accurate color-magnitude diagram of this cluster. More information is available from Gemini press release. The full results are published in The Astrophysical Journal and a preprint is also available.