6 ms·

The rule is 5 years. You've given 2 examples under 5 years. If everything is going to re-enter within 5 years without boosting then your point is moot, because

by bisby 4y ago

The rule is 5 years. You've given 2 examples under 5 years. If everything is going to re-enter within 5 years without boosting then your point is moot, because even in your "massively more collision risky" example, it still abides by the rules. If something was going to deorbit within 1 minute, or was going to deorbit within 4 years, 6 months... It doesn't matter to the creator, because they don't have to change their design at all to meet the rules. If something was going to deorbit within 8 years (because they previously had a 25 year allowed limit), they now have to rework the design. There's plenty of room for debate about if 5 years is adequate, but as it stands, _most_ things (under 500km) will naturally deorbit within the legal time frame anyway even without special consideration.

mikeyouse 4y ago
Just responding to a comment that said "If deorbiting in years is sufficient, the difference in time is not relevant" where it's obviously relevant.. this doesn't seem remotely controversial.
- bisby 4y ago
  You're arguing a different thing. The topic was satellite design for satellites under 450km. If deorbiting in years is sufficient, the difference in 1 minute vs 4 years is NOT relevant -> to a satellite builder worried about the law. If everything deorbits within 5 years, the only way for more things to accumulate is to launch things faster. But that's a separate discussion. If everything launched today is deorbited within 5 years, then in 5 years, all satellites will be new satellites launched after today. If everything launched today is deorbited within 5 months, then in 5 years, all satellites will be new satellites launched after today. Deorbit speed under a threshold has no bearing on accumulation beyond that threshold. If SpaceX launches a trillion Starlink satellites, and they all deorbit within a year, then yes. it's going to be a very crowded year, and we'll have to drastically rethink how much stuff we have in LEO, but at the same time SpaceX would not be in violation of the 5 year deorbit window, so the issue is about how much stuff we're sending up, and not how fast it de-orbits. "Amount of junk below 450km, total" and "Amount of junk below 450km, that hasn't deorbited after 5 years" are very different things. You're making points about total, while the original point was about deorbit speed.
- s1artibartfast 4y ago
  Let me put this another way, if I use my computer to send emails, it doesn't matter to me if my ping is 10 milliseconds or 10 femtoseconds. One time is 10^12 times longer, but the difference does not matter to me. My emails are still sent and received faster than I can possibly perceived.

by bisby 4y ago

mikeyouse 4y ago

Just responding to a comment that said "If deorbiting in years is sufficient, the difference in time is not relevant" where it's obviously relevant.. this doesn't seem remotely controversial.

bisby 4y ago
You're arguing a different thing. The topic was satellite design for satellites under 450km. If deorbiting in years is sufficient, the difference in 1 minute vs 4 years is NOT relevant -> to a satellite builder worried about the law. If everything deorbits within 5 years, the only way for more things to accumulate is to launch things faster. But that's a separate discussion. If everything launched today is deorbited within 5 years, then in 5 years, all satellites will be new satellites launched after today. If everything launched today is deorbited within 5 months, then in 5 years, all satellites will be new satellites launched after today. Deorbit speed under a threshold has no bearing on accumulation beyond that threshold. If SpaceX launches a trillion Starlink satellites, and they all deorbit within a year, then yes. it's going to be a very crowded year, and we'll have to drastically rethink how much stuff we have in LEO, but at the same time SpaceX would not be in violation of the 5 year deorbit window, so the issue is about how much stuff we're sending up, and not how fast it de-orbits. "Amount of junk below 450km, total" and "Amount of junk below 450km, that hasn't deorbited after 5 years" are very different things. You're making points about total, while the original point was about deorbit speed.
s1artibartfast 4y ago
Let me put this another way, if I use my computer to send emails, it doesn't matter to me if my ping is 10 milliseconds or 10 femtoseconds. One time is 10^12 times longer, but the difference does not matter to me. My emails are still sent and received faster than I can possibly perceived.