Satellite mirror plans could disrupt sleep and ecosystems worldwide, scientists say

Letters to US agency raise concerns over tech firms' plans to use reflective satellites and expand numbers in low Earth orbit

Proposals to deploy reflective mirrors and up to 1m more satellites in low Earth orbit could have far-reaching consequences for human health and ecosystems, leading sleep and circadian rhythm researchers have said.

Presidents of four international scientific societies representing about 2,500 researchers from more than 30 countries are among those who have raised concerns in letters to the US Federal Communications Commission (FCC).