After decades since the beginning of the space era in 1957, with the launch of the first satellite, Sputnik, a lot changed in the space arena, and currently we face thousands of satellites orbiting our planet in low earth orbit (300-1000km). Orbits are becoming congested and contested, and ensuring the safety, security and sustainability of outer space activities is becoming a difficult challenge.

The increase in the number of satellites launched per year has been progressive year after year, but it was in 2019 that the situation started to become more complex, when mega-constellations came into play.

Soon SpaceX will have 42000 satellites in orbit with the aim of connecting everyone everywhere. While serving a very high purpose of bridging the digital divide and supporting the creation of new markets, the price to be paid by astronomers seems to be high. Two main factors have an impact on maintaining Dark and quiet skies: (1) satellites reflect from sunlight and Earth albedo (2) they emit from radio transmissions and thermal radiation. The main question is therefore the following: how to prevent or minimize these effects?

The symposium has therefore the main goal of allowing the different voices to be heard, with the aim of ensuring sustainability in space activities preserving dark and quiet skies for astronomers of today and tomorrow. At the same time, the symposium will allow for mega-constellations to be considered strong supporters of space science and will investigate ways and means to help space scientists to better perform with their investigations.