The accelerated expansion of the universe due to dark energy does not require a recalibration of distances to distant stars and galaxies in light-years (ly). The concept of a light-year remains the same, representing the distance that light travels in one year.
The accelerated expansion of the universe affects the scale of the universe itself, causing the expansion to accelerate over vast distances. However, this does not directly impact the way we measure distances using light-years.
Distances to distant stars and galaxies are typically determined through various methods, such as parallax, redshift, and standard candles (like supernovae). These methods rely on observational techniques and physical properties of objects to estimate their distances. While the expansion of the universe affects the redshift of light from distant objects, which is used to measure their distances, the concept of the light-year as a unit of distance remains unchanged.
It's worth noting that over extremely large cosmic distances, the expansion of the universe can cause significant redshift, which affects the observed wavelengths of light. This effect needs to be accounted for when calculating the distances to very distant objects. However, it does not require a fundamental change in the definition or usage of the light-year as a unit of distance.
In summary, the accelerated expansion of the universe does not necessitate a recalibration of distances to distant stars and galaxies in light-years. The light-year remains a consistent and widely used unit of distance for measuring cosmic distances.