The Milky Way and its Group
Our solar system belongs to a large spiral-shaped group of stars called the Milky Way Galaxy, which is about 100,000 light years across. The next-nearest large galactic neighbor is the Andromeda Galaxy (M31), located 2.5 million light-years away. It is also a spiral galaxy and similar in size to the Milky Way Galaxy. Between Andromeda and the Milky Way galaxies lie dozens of smaller ones. The interactions between members of this galactic group provide us with important clues when we try to understand the mechanism of how galaxies are formed. By studying stars in the Milky Way Galaxy, we can also probe the signatures of the first generation of stars formed after the Big Bang.
Comment from researchers
The Subaru Telescope excels at wide-field imaging and succeeded in discovering the halo structure of a dwarf galaxy for the first time. Thanks to this discovery, we now know that even a dwarf galaxy has a complex history of formation. The Subaru Telescope is expected to conduct systematic studies of halo structures of galaxies in our local group.
Dr. Nobuo Arimoto
(Seoul National University)