Huh. I wasn’t worried before reading this thread. Now I’m a little more worried.
1. We don’t need to worry about Kessler syndrome, as the orbits of Starlink will decay in five years (from 550km).
2. ISS is at 420km.
Has anyone else ever worked with something dangerous dangling over their heads? It’s kind of nerve wracking, even if you know that there’s very little chance of it falling and hitting you.
(Main body) Size matters a lot. That 7m estimate above is with a solar array unfurled and is much larger than the main body, which is about 3.2m x 1.6m x 0.2m[0]. These will burn up in the atmosphere, and actually are designed to do so.
Are you afraid of airplanes flying overhead? Probably not. These don't burn up in the atmosphere and when they fall they do a ton more damage than satellites that don't. A big reason you're not afraid is because the chance of you (or any person) being hit is pretty small because the object is so small compared to the potential falling area. Now we're talking about objects that are significantly smaller than airplanes and with a potential "falling area" (if somehow something doesn't burn up) is magnitudes larger and into an area that is basically empty (humans don't even occupy 15% of the surface).
You shouldn't be worried. Even if parts of these things were hitting the ground they wouldn't be that dangerous just due to the statistics of being hit. Odds get even better when we talk about typical orbits.
The satellites can't just fall out of the sky suddenly like something hanging above your head. That's not how orbital mechanics works. ISS would have warning of any threat long in advance, plenty of time to make an avoidance maneuver or return to Earth in their lifeboat.
The satellites are expected to control their deorbit, just as they controlled their ascent, and neither controlled ascent nor controlled descent pose any threat to ISS. If a satellite failed in orbit and was unable to control its deorbit, it is still very unlikely that it would come anywhere close to colliding with ISS on the way down. And in the very unlikely event that it did, again there would be plenty of advance notice for ISS which could do a maneuver to avoid it.
There's no real chance of starlink satellites falling and hitting you.
They're designed to fall out of orbit at the end of their lifespan (or whenever something goes wrong), and fully burn up in the atmosphere before reaching the ground.
The moon is gaining velocity from earth’s rotation which is a finite energy source, given a long enough timescales it would collide with earth. However, the sun is going to consume the earth before that happens.
1. We don’t need to worry about Kessler syndrome, as the orbits of Starlink will decay in five years (from 550km). 2. ISS is at 420km.
Has anyone else ever worked with something dangerous dangling over their heads? It’s kind of nerve wracking, even if you know that there’s very little chance of it falling and hitting you.