Reflect Orbital

Eärendil-1 is a satellite of roughly 135 kilograms that unfolds four triangular panels of aluminium-coated film into a mirror eighteen metres on a side. The film weighs about sixteen kilograms and is a few thousand atoms thick. In orbit it would steer reflected sunlight onto a patch of ground some five kilometres across for four or five minutes as it passed, appearing within that patch around four times brighter than a full moon. The intended customer is a solar farm wanting to generate into the evening demand peak, with search and rescue, event lighting and military illumination named as secondary markets.

Ben Nowack's argument is that the fundamental limit on solar power is the night, and that reflecting sunlight down is cheaper than storing it. Reflect quotes about $2 million for the prototype and $300,000 for production units, which is the real wager: make the mirrors cheap enough that the physics can be brute-forced with tens of thousands of them.

The strongest criticism is about the physics. The Sun is half a degree wide as seen from Earth, so sunlight bouncing off a flat mirror necessarily spreads; from 800 kilometres up the illuminated patch is at least seven kilometres across, and curving the mirror does not help, because the limit is the size of the Sun rather than the quality of the optics. Michael Brown and Matthew Kenworthy calculate that one large satellite delivers light roughly fifteen thousand times fainter than midday sun, so Reflect's own target of 200 watts per square metre would need something like three thousand satellites lighting one spot at once. A peer-reviewed European Southern Observatory study published in July 2026 found the proposed constellation would make the night sky three to four times brighter everywhere, including the darkest observing sites on Earth, and that these would be the brightest objects ever placed in orbit. The American Astronomical Society formally petitioned the regulator to deny the licence. The FCC granted it in July 2026 anyway. Reflect's own filings to that regulator acknowledge the possibility of permanent eye damage to someone looking through a mid-sized telescope as the beam passes. Nothing has flown: the only physical demonstration is a two-and-a-half metre mirror on a hot-air balloon, 242 metres up, in March 2024.