It's an interesting idea. For a civilisation is constructing a Dyson swarm, the time required to build a 20% coverage one to 30% one should be less than a decad

It's an interesting idea. For a civilisation is constructing a Dyson swarm, the time required to build a 20% coverage one to 30% one should be less than a decade. If I remember correctly, NASA is already be able to observe 1% of the difference. So we only need to wait for a year.