The reason the positions of the stars in the sky remain largely unchanged, despite the Sun carrying the Earth through space at incredible speeds, is due to the vast distances between stars.

The reason the positions of the stars in the sky remain largely unchanged, despite the Sun carrying the Earth through space at incredible speeds, is due to the vast distances between stars.

Key Factors:

1. Immense Distances:

Stars are located at distances measured in light-years. Even the closest star to us, Proxima Centauri, is about 4.24 light-years away. The movement of the Sun (6.9 billion km per year, or about 0.00073 light-years) is minuscule compared to these vast distances.

2. Relativity of Motion:

All nearby stars and our entire Solar System are moving together as part of the Milky Way’s rotation. While there are relative motions among stars, they are extremely small over short timescales (like a human lifetime), making the night sky appear almost static.

3. Proper Motion is Slow:

Some stars do exhibit "proper motion" (small shifts due to their individual movements), but these shifts are very slow. For example, Barnard’s Star, one of the fastest-moving stars relative to Earth, shifts by just 10.3 arcseconds per year—equivalent to the width of a penny viewed from about 3.5 kilometers away.

Observable Changes:

Over thousands of years, the constellations will slowly change due to this motion. Historical records show that ancient star charts differ slightly from today's observations, proving that stars do move over very long periods.

Thus, while the Sun and Earth travel enormous distances through space, the sheer scale of the universe ensures that the night sky appears almost unchanged over human timescales.