Figure 1.
Gemini Observatory
near-infrared image
of the globular cluster
Liller 1 obtained with the
GeMS adaptive optics
system on the Gemini
South telescope in Chile.
This image is featured on
the cover of this issue.
“Although our Galaxy has upwards of 200 billion stars, there is so much vacancy between
stars that there are very few places where
suns actually collide,” said Douglas Giesler
of the University of Conception in Chile and
Principal Investigator of the original observing proposal. “The congested overcrowded
central regions of globular clusters are one
of these places. Our observations confirmed
that, among globular clusters, Liller 1 is one
of the best environments in our Galaxy for
stellar collisions.”
The unprecedented ultra-sharp view of the
cluster reveals a vast city of stars estimated
by the team to contain a total mass of at
least 1.5 million suns, very similar to the two
most massive globular clusters in our Galaxy: Omega Centauri and Terzan 5.
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GeminiFocus
Geisler’s team specializes in the study of
globular clusters near the center of the Milky
Way, while Ferraro’s team is adept at the reduction of infrared data on globular clusters.
Both groups worked together to obtain the
beautiful and detailed observations of Liller
1 with Gemini.
The observations of the tightly packed cluster used Gemini Observatory’s powerful
adaptive optics system at the Gemini South
telescope in Chile.
A technical jewel named GeMS (derived from
“Gemini Multi-conjugate adaptive optics
System”), in combination with the powerful
infrared camera Gemini South Adaptive Optics Imager (GSAOI), was able to penetrate
the dense fog surrounding Liller 1 and to
July 2015