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.
years away from the center of the Milky Way
— in one of the most inaccessible regions of
our Galaxy, where thick clouds of dust prevent the optical light from emerging. “Only
infrared radiation can travel across these
clouds and bring us direct information on
its stars,” comments Emanuele Dalessandro,
also of the University of Bologna.
“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,” says 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
70
GeminiFocus
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.
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.
2015 Year in Review
January 2016