Proxima Centauri and Barnard's Star: A Century's Journey

Charles Sutherlin's answer to the question of how far Proxima Centauri and Barnard's Star are estimated to be from the Sun in a century is excellent and provides a clear perspective on stellar velocities. Understanding the distances and movements of these stars is crucial for researchers and enthusiasts alike.

Understanding Stellar Velocities

Sutherlin explains that stellar velocities are a few (10^{-4}c) relative to each other, meaning they move at about random variations around their common (10^{-3}c) orbits around the galaxy. This fact is pivotal because it helps us grasp the scale of movement.

Starry objects like Proxima Centauri and Barnard's Star move relative to us at a few ten-thousandths of a light year per year, and a few hundredths of a light year per century. Therefore, to see significant changes in their positions relative to the Sun, we would need to wait for 100 centuries.

Barnard's Star: Moving at a Celerity

Barnard's star, for instance, has a radial velocity of -110 km/s, which translates to a movement of approximately (3.7 times 10^{-4}) light years per year. In a century, this star will have moved about 5.921 light years from its current position at 5.9583 light years away from the Sun.

Visualizing the Movement

For a more detailed view of the movement, one can refer to the graph on the Wikipedia page for Barnard's Star. This graph provides an excellent visual representation of how these stars have moved and will continue to move relative to the Sun.

Distance Between Sol and Barnard's Star

The Wikipedia entry for Barnard's Star also includes a map that shows the distance between the Sun and Barnard's Star as being about the same as the distance from the Sun to Proxima Centauri. This information is invaluable for understanding the relative positions of these stars.

The distance between Sol and Barnard's Star is approximately 5.9583 light years, and as mentioned earlier, in a century, it will be about 5.921 light years away. This small change in distance illustrates the delicate balance of stellar movements.

Conclusion

In summary, while a century is barely long enough for noticeable movement relative to the Sun for these stars, it is a significant span in human terms. Understanding the precise movements of these neighboring stars can deepen our knowledge of the universe and its vast expanses.