hawklost t1_j24tvfk wrote on December 29, 2022 at 5:49 PM

Reply to comment by Sh36fjk374fjc in SpaceX launches 54 upgraded Starlink internet satellites and nails rocket landing at sea in 60th flight of the year by ovirt001

There are about 12.3 thousand satellites orbiting in space

Now, if you were to take 12 thousand people and have them run around the US, would you be worried they would hit each other?

Since most might try to counter. Yes, the satellites are moving quicker, but at the same time, they are in orbits at different levels too.

So imagine that everyone is in a huge building, the biggest you have ever seen. Now imagine that that building has 100 copies of it physically (orbital distance of space). Now put those 12k people in any of the 100 buildings randomly and tell them to walk or run around, but I'd they see another, to intentionally avoid them.

That is what space is like

Frozenthia t1_j26xe85 wrote on December 30, 2022 at 2:18 AM

That changes when those people can break into a thousand pieces and travel at thousands of miles per hour.

hawklost t1_j274rdr wrote on December 30, 2022 at 3:12 AM

I assume you didn't bother reading the post afterwards explaining that extra piece for the person.

Secondly, the reason I am using a building size multiplied by 100 is for the idea of someone walking around AS IF they were moving such speeds, but Also that you need to take into account different orbits, which is effectively hundreds of different 'buildings' in the example I gave (Would have chosen floors, but people don't experience super large single story buildings so wouldn't get the vastness as easily). So the 'thousands of miles per hour' part is already there.

To give you context Otherwise. The US alone has 100,000 flights a day. The US is approximately 6.1% of the world by landmass. Planes can travel up to 500 or so mph. while satellites go at 17,000 mph. There are about 12.5k satellites over earth. Satellites also go above the earth by about an extra 10-20% (important because amount of space grows). So to give an idea without using people as an analogy.

To give you an idea, the likelihood of 2 planes crashing in mid-air in the US is far more likely than 2 satellites crashing in orbit. Even when you take speeds into consideration.

Frozenthia t1_j2by5pg wrote on December 31, 2022 at 2:53 AM

The biggest thing is that you don't need to just worry about other satellites, and the second is that the orbital material can exist at any altitude that satellites are orbiting at.

In terms of debris that can cause Kessler syndrome, 100k is a miniscule number. At the speed of a satellite, it does not take much to do serious damage and destruction. Your planes only have to worry about 100k planes, while satellites have to worry about motes of dust. If planes had to worry about that as well, we'd have serious issues flying at 500mph.

And United States Space Surveillance Network has identified this:

36500 space debris objects greater than 10 cm

1000000 space debris objects from greater than 1 cm to 10 cm

130 million space debris objects from greater than 1 mm to 1 cm

A single satellite being destroyed can be enough to turn 1 satellite into thousands, perhaps even tens or hundreds of thousands of pieces of individual debris that can then annihilate the rest at the same orbital level over time.

The change in momentum can be enough to cause concern.

This is such a very deeply important topic that it really does require a lot of protection, planning, redundancies, etc. SpaceX just doesn't seem like it has done enough to address this. There's a reason that NASA has moved more slowly and beat private companies to Mars, and it's because every single detail - every single detail of material science, chemistry, thermodynamics, physics, etc, has been meticulously vetted to the letter.

Falsely believing as a private company that "Wow, they're all foolish, this was easy, all we had to do was shove some satellites at this other altitude" and not putting enough merit in Kessler syndrome is a very big mistake.

Sh36fjk374fjc t1_j24ujwo wrote on December 29, 2022 at 5:53 PM

Interesting points! Idk though, this NASA dude mentioned above thought it was quite possible.

https://en.m.wikipedia.org/wiki/Kessler_syndrome

Edit: “On average one satellite is destroyed by collision with space junk each year.[22][24] As of 2009 there had been four collisions between catalogued objects, including a collision between two satellites in 2009.[4].”

Sounds like it is more than just a probability but a reality.

hawklost t1_j24vbht wrote on December 29, 2022 at 5:58 PM

Yes it is possible. Although the fear is less two satellites crashing into each other and more the fear that a satellite will break up and create thousands of little pieces that could crash into More satellites.

To take the analogy I used before farther.

Now imagine two people Do run into each other, either because one wasn't paying attention or by malicious design. Now picture 1000 hyperactive kids being produced off of that collision. They aren't going to pay attention and will just run around bouncing off the walls, jumping between buildings as they want.

Yes, some will leave the buildings altogether, but many will be around due to orbital dynamics (not getting into that here). So now each person walking around has to watch for other people, And screaming children who don't pay attention (literally can't they aren't self driving).