Time-lapse photography of the Lyrid meteor shower from April 2020. At the 0:50 mark, a train of Starlink satellites zooms through the landscape.
With the naked eye, stargazing from a dark-sky location allows you to see about 4,500 stars. From a typical suburban location, you can see about 400. Simulations show that from 52 degrees north (the latitude of both Saskatoon and London, U.K.) hundreds of Starlinks will be visible for a couple of hours after sunset and before sunrise (comparable to the number of visible stars) and dozens of these will be visible all night during the summer months.
Light pollution has long been a threat to stargazing, but at least that can be escaped by leaving urban centers.
But satellites will be a global star-obscuring phenomenon, particularly bad at the latitudes of northern U.S. states, Canada and much of Europe.
Stellar sacrifices
To their credit, SpaceX and Amazon —
which is also investing in satellite internet services — have voluntarily started participating in discussions with professional astronomers on possible ways to mitigate the effects of thousands of bright satellites on specific observations, like interstellar objects.
SpaceX did also try a “darksat” coating, though
preliminary measurements by astronomers showed that it was
only marginally fainter than other Starlinks. Meanwhile, launches continue with unmitigated, bright Starlinks.
Simulations show that
professional astronomy and
amateur astrophotography will be severely affected by bright mega-constellations. Discoveries of hazardous near-Earth asteroids will be
particularly devastated by the hundreds of Starlinks confusing their targets, leaving Earth more
vulnerable to
world-altering impacts.
The point of the Starlink mega-constellation is to provide global internet access. It is often stated by Starlink supporters that this will provide internet access to places on the globe not currently served by other communication technologies. But currently available
information shows the
cost of access will be too high in
nearly every location that needs internet access. Thus, Starlink will likely only provide an
alternate for residents of wealthy countries who already have other ways of accessing the internet.
Crowding the night sky
Even if SpaceX changes its plans, other companies are
actively developing separate megaconstellations, and
there are more in the works.
Currently, there are no rules about satellite orbits or right-of-way, and if a collision (or multiple collisions) should occur, it’s not clear who would be at fault and who would have to clean up the debris (if that is even possible to do). The
only international law that applies to satellite debris, from 1972, basically says that the country who launched the satellite has to clean up any mess it leaves on the surface of the Earth after crashing.