Reflect Orbital Company placed two Indian rockets in preparation for testing an unprecedented service of selling sunlight reflected from outer space, arousing much controversy.

According to Conversation, California-based startup Reflect Orbital plans to place giant mirrors in low Earth orbit to direct reflected sunlight to selected locations on the ground. They want to sell space-based lighting services for a variety of purposes, from keeping solar farms running after dark to aiding search and rescue. The company's first test device is the Eärendil-1 satellite that will launch next year with a reflector measuring 18 x 18 m.

The idea of ​​using mirrors in space to provide useful light requires overcoming daunting technical challenges. Reflect Orbital says this type of mirror can illuminate a customer's solar farm or specific rescue site without affecting other areas. However, the reality is much more complicated because the Earth's atmosphere will scatter light rather than gather it along a clear boundary.

Scientific research published last August in the journal IOP Science simulated the process of sunlight reflecting through the atmosphere, with molecules and aerosols dispersing part of the radiation beam across the sky. When projected onto the ground, they are reflected back up and continue to diffuse, causing the phenomenon to affect a much wider area than intended.

For the 54 m mirror that Reflect Orbital plans to use, the falling light can extend significantly beyond the target area. At a position 14 km away from the beam of light, the sky was still brighter than a full moon night. Even at a distance of 34 km, when looking towards the beam, the sky still looked brighter under the full moon.

Although this is a prediction based on a model, not a measurement from a real space mirror, the study results expose the problem that many people are likely to be affected by the company's services. Reflected light can affect natural shadows over a larger area than the client requires.

According to Guardian, on October 10, Reflect Orbital placed high-powered mobile floodlights on the ground near the town of Lone Pine and the Mount Whitney area in the Sierra Nevada region, California to simulate light from satellite-mounted reflectors in the future. However, some locals described the beam as "blinding".

In July, the US Federal Communications Commission (FCC) licensed Reflect Orbital to deploy and operate Eärendil-1. But the license only covers radio communications, specifically the use of certain frequencies to control and monitor satellites.

In August, four organizations represented by Earthjustice asked the FCC to reconsider the approval due to concerns that reflective satellites would cause a series of problems. Animals such as birds, insects and mammals rely on a steady alternation of day and night for food, shelter and mating, so any change could spell disaster for them. Similarly, day-night disturbance will harm human health by disrupting circadian rhythms.

Meanwhile, astronomers complain that night lighting will worsen existing light pollution, obscure stars and cause more space junk to fall back to the ground. They asked the FCC to adopt safeguards to minimize unintended optical impact. However, the agency refused because the field of astronomy was outside the scope of their regulations.

Reflect Orbital's deal with India's Skyroot Aerospace includes two separate launches using the development Vikram-1 and Vikram-1U rockets. Each launch from India requires approval by the Indian National Space Promotion and Authorization Board (IN-SPACe), based on safety regulations, registration and environmental impact. They often require limiting negative impacts on the environment (on Earth or in space), as well as adverse changes to the atmosphere. Meaning, India may face an issue that the FCC avoids. There is currently no information on how IN-SPACe will handle intentionally reflected light.

While Reflect Orbital is an American company, the Skyroot rocket and launch site are in India. The Eärendil-1 satellite can illuminate the territory of a third country. Atmospheric scattering means its effects can spread beyond the target area. The question to be resolved is if a commercial operator wants to light a location in another country, will they need a license from the authorities there?

However, Eärendil-1 can provide real data for managers: measuring brightness, atmospheric dispersion and the ability to control reflected light. Reflect Orbital said it will continue to work with astronomers, the community and regulatory agencies when expanding the scale of testing.

An Khang summary