Milky way diameter in light years
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Milky Way Galaxy Diameter in Light Years
Overview of the Milky Way's Size
The Milky Way galaxy is a vast, spiral-shaped system of stars, gas, and dust. Its diameter is commonly measured in light years, a unit representing the distance light travels in one year.
Consensus on the Milky Way's Diameter
Most research sources agree that the Milky Way's diameter is about 100,000 light years. This measurement refers to the luminous disk of the galaxy, which contains the majority of its stars and visible matter 13. The disk is much thinner compared to its width, being about 12,000 light years thick near the center and narrowing to about 1,000 light years at the edges .
Alternative Estimates and Historical Context
Some sources and historical models have suggested a smaller diameter, around 50,000 to 60,000 light years, based on earlier astronomical observations and models 26. However, more recent and detailed measurements support the larger figure of approximately 100,000 light years 13.
Position of the Solar System
Our Solar System is located about 25,000 to 26,000 light years from the center of the Milky Way, placing us roughly two-thirds of the way from the center to the edge of the galaxy 14.
Comparison with Other Galaxies
For context, the distance between the Milky Way and its nearest large neighbor, the Andromeda Galaxy, is about 2.2 million light years—roughly 20 times the diameter of the Milky Way itself .
Conclusion
In summary, the Milky Way galaxy has a diameter of about 100,000 light years, making it a massive structure in the universe. While older estimates suggested a smaller size, current understanding based on modern observations supports this larger measurement.
Sources and full results
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