- Reflect Orbital is going to launch an 18 meter test satellite named ‘Earendil-1’ next year i.e. in 2026. The company says that this project will turn into a network of about 4,000 satellites by 2030.
- Each satellite will have a 54 meter wide mirror which will focus sunlight on some part of the Earth. Its purpose is to provide ‘artificial sunlight’ to solar farms at night so that they can generate electricity even at night.
- Reflect Orbital says it aims to provide just 200 watts per square meter of light, which is about 20% of midday sunlight. That means enough light that the solar panels remain active, but darkness does not disappear completely.
How will ‘Sunlight on Demand’ work?
- This system will actually reflect sunlight on the earth through mirrors. Just as you cast sunlight on the wall from the glass of your watch, similarly these satellites will cast sunlight from space on the Earth.
- But the difference is that this experiment will be conducted from a height of 625 kilometers. It is not easy to focus light from so high. According to scientists, at this distance the bundle of sunlight will spread over an area 7 kilometers wide. That means the light will not be bright, it will be diffused and dim.
- The light from a single satellite will be 15,000 times less than that of midday sunlight, but still brighter than full moonlight.
Test done with balloon, but matter is different in space
Last year, company founder Ben Novak conducted a test. He placed a 2.5 meter wide mirror on a hot air balloon and reflected sunlight onto the solar panel below it.
The test measured illuminance of about 516 watts per square meter, which is about half the strength of the midday sun. That means the technology works. But when the same experiment is done from 800 kilometers above, the mirror will have to be made 6.5 kilometers long. Which is practically impossible.
3,000 satellites are needed to illuminate just one place
- The company says that to provide 20% sunlight from a 54 meter satellite, about 3,000 satellites will be required. That too only for one area and for a few minutes.
- Because a satellite rotating at a height of 625 kilometers can remain at any one place only for 3.5 minutes. Meaning, if light has to be provided for one hour, thousands more satellites will have to be installed.
- Ben Novak had said in an interview that he can launch up to 2.5 lakh satellites in the future. Imagine, this huge number is more than all the existing satellites and space junk combined.
Scientists said – this is not light, it is danger
- This news is scary for astronomers. According to Monash University astronomer Michael Brown, ‘If these satellites start working, then spots brighter than the moon will be visible in the sky all the time.’
- Astronomer Matthew Kenworthy of Leiden University says, ‘This will not only destroy astronomy, but can also harm the eyes of people looking through telescopes. The surface of every mirror will shine like the sun.
- Scientists say that so much artificial light will not only affect astronomy, but can also spoil the biological clock of birds, animals and humans. The darkness of night, which is an essential part of the Earth’s biology, will end.
Reflect Orbital’s clarification – ‘We will be predictable and safe’
The company says that it will keep this technology ‘predictable and controlled’. That means the beams will be sent only to the required area. Also, the company will maintain coordination with the observatories so that astronomy is not harmed.
In an interview given to Bloomberg, the company said that it will divert the beams from ‘sensitive areas’ and the location of the satellites will be shared in advance so that scientists can prepare.