Osteopenia refers to bone density that is lower than normal peak density but not low enough to be classified as osteoporosis. Bone density is a measurement of how dense and strong the bones are. If your bone density is low compared to normal peak density, you are said to have osteopenia.steopenia refers to bone density that is lower than normal peak density but not low enough to be classified as osteoporosis. Bone density is a measurement of how dense and strong the bones are. If your bone density is low compared to normal peak density, you are said to have osteopenia.
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.
NASA estimates the galaxy at 100,000 light-years across. Since one light year is about 9.5 x 10 12 km, so the diameter of the Milky Way galaxy is about 9.5 x 10 17 km in diameter. The thickness of the galaxy ranges depending on how close you are to the center, but itâs tens of thousands of light-years across.Our galaxy is part of a collection known as the Local Group.ince one light year is about 9.5 x 10 12 km, so the diameter of the Milky Way galaxy is about 9.5 x 10 17 km in diameter. The thickness of the galaxy ranges depending on how close you are to the center, but itâs tens of thousands of light-years across.