Pigs_in_the_Porridge t1_jadw2hn wrote on February 28, 2023 at 7:01 PM

Reply to comment by theexile14 in We need more rules for space junk and moon bases, NASA and US officials say by DevilsRefugee

You're missing the issue of collisions in LEO & possible Kessler syndrome (orbits so filled with junk everything gets shredded).

Spider_pig448 t1_jae09zw wrote on February 28, 2023 at 7:27 PM

Kessler syndrome is mostly a thought experiment, similar to the possibility of a nuclear chain reaction igniting the atmosphere. Space junk in LEO isn't a huge concern, partially because LEO is already unburdened by the early space age and all the waste created from it.

Pigs_in_the_Porridge t1_jae12be wrote on February 28, 2023 at 7:32 PM

What do you know that the world's space agencies don't? They have publicly expressed concern about space junk in LEO making some orbits, like those around 400 miles or so, unusable at some point in the future. Chinese and Russian ASAT tests have added thousands of pieces of debris. Just saying it's not an issue is not in the least convincing.

Spider_pig448 t1_jae1yz9 wrote on February 28, 2023 at 7:38 PM

It is an issue. ASAT tests and cyber attacks in particular are huge concerns for space debris generation. Regular generation of space junk per launch is decreasing a lot though. Check out ESA's environmental report from last year (https://www.esa.int/Space_Safety/Space_Debris/ESA_s_Space_Environment_Report_2022). Almost every rocker body is successfully clearing LEO these days, and half of all payloads are being successfully de-orbited after end of mission.

theexile14 t1_jae7zee wrote on February 28, 2023 at 8:16 PM

I have worked in space debris tracking before. I'm not forgetting anything. Low LEO clears in a relatively short period of time, it is not at serious risk. High LEO...I mentioned? You seem to be freaked out that I didn't mention a specific term that's become overly common amongst those who don't understand the environment.

The most serious risks to High LEO are what I mentioned: ASATs and breakups of non-operating satellites. If those continue to happen unabated for some time then we can start to worry about Kessler Syndrome. Too many people watched Gravity and took it as a real risk.

myflippinggoodness t1_jaey5bz wrote on February 28, 2023 at 11:10 PM

Ok, mby you're someone to ask about this: what if they put up like a big, heavy metal shield just to float around, let small shit smash into it, just so the small shit loses velocity and falls into LOW LEO so that it falls in like a couple years instead of a couple centuries?

Hopes like I'm 5 👌

theexile14 t1_jaf082x wrote on February 28, 2023 at 11:24 PM

There are ideas about doing that with some gel type substance to capture junk. Unfortunately, a large metal object doesn't work as the collisions may occur at relative speeds of hundreds or thousands of km/hr. At that speed you mostly just smash things into pieces and send the careering all over. Unfortunately that hurts more than helps.

Also, that mass would be huge and cost a ton to put into orbit.