Flail Chest (Definition) Flail chest is a life threatening medical condition in which multiple segments of the rib cage have been broken and are loosened. These segments cause severe bruising and damage to the lung. ...Read more.
The Milky Way is the second-largest galaxy in the Local Group, with its stellar disk approximately 100,000 ly (30 kpc) in diameter, and, on average, approximately 1,000 ly (0.3 kpc) thick.
A galaxy may range in diameter from some hundreds of light-years for the smallest dwarfs to hundreds of thousands of light-years for the largest ellipticals, and may contain from a few million to several trillion stars.