The Brightened Night Sky Nobody Actually Wanted
A new study modelling Reflect Orbital's proposed constellation of giant orbital mirrors finds their light pollution would be severe. A single 54 metre satellite would appear four magnitudes brighter than the full moon to anyone in its beam, and its scattered glow would outshine moonlight across the sky from 14 kilometres away, remaining visible from over 30 kilometres out. With the pilot…
A California company named Reflect Orbital has proposed a plan to place giant mirrors in orbit and use them to beam sunlight down to Earth after dark. The plan has been outlined in a new paper that has been accepted for publication in Astrophysical Journal Letters. The pilot satellite, Eärendil-1, features an 18-by-18-meter reflector flying at an altitude of around 600 kilometers.
Its purpose is to create a patch of daylight covering a 2.5-kilometer area on the ground when requested by a customer. However, the proposal has sparked controversy due to its potential impact on night sky brightness. According to the paper, a single 54-meter satellite would appear brighter than a full moon from just 14 kilometers away and would scatter light throughout the sky, making it difficult to observe stars.
If 400 of these satellites were deployed together, the glow would become visible from 80 kilometers away, creating a dusk-like background that would significantly impact astronomical observations. The FCC approved the project despite thousands of public comments and objections from astronomy groups, as they do not consider it their responsibility to regulate light pollution or astronomical interference.
Written by urgent.news from Phys.org's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
