Cleaning Up Long-Exposure Andromeda Photography

• Astronomers released a comparison showing how raw long-exposure data of the Andromeda galaxy (M31) is processed to remove terrestrial artifacts.
• The source images consist of 223 individual 300-second exposures captured at a private observatory in Portugal in 2019.

Data Cleanup and Software

• The raw captures contained significant artifacts, including satellite trails, airplane light streaks, cosmic ray noise, and bad pixels.
• Processing involved specialized software packages—Astro Pixel Processor, DeepSkyStacker, and PixInsight—rather than simple image editing.
• The goal of this technical intervention is to minimize Earth-based interference, providing a more accurate representation of the distant galaxy rather than creating a digital fantasy.