
Kessler Syndrome - msvan
https://en.wikipedia.org/wiki/Kessler_syndrome
======
danielvf
If a satellite is in a very low orbit then any debris fall to earth quickly.
Almost all cubesats have a orbital life of six to five years. The space
station, in a normal low earth orbit, would hit the earth in around three
years without reboosts.

The higher you go, the more absolute volume there is, the slower the
satellites there travel and the fewer satellites there are.

So that leaves a band of mid-upper LEO satellites to consider for Kessler
Syndrome.

When you have a collision between satellites, the velocity on average of each
fragment is less than it was before, making the fragments decay faster. The
fragments after each collision are smaller than they were before as well, thus
having more air and solar resistance, which also makes them decay faster.

The Chinese FY-1C satellite that was blown up was the absolute worst case for
a satellite explosion. It was located on the high side of LEO with a decay
time measured in human generations, and it was in a super crowded sun-
following orbit altitude, sharing space with lots of weather and earth
observation satellites. The explosion generated 150,000 debris fragments.

In the ten years since, most of those fragments have reentered. We now have
2,000 golfball sized or bigger fragments being tracked, and over the past ten
years, the only casualty has been a small, ten pound reflector satellite.
Small debris pieces fall, and big pieces can be tracked and avoided.

If every satellite we have put into space magically exploded, and the debris
was magically moved to a high LEO altitude and evenly distributed to avoid any
holes, then we could still launch through this orbit of death to higher
altitudes with only a 1 in 1000 probability of impact.

Space regulation has gotten much tougher since the bad old days. Satellites
are now required to have deorbit or safeing plans, and the median satellites
size has gone down by a couple orders of magnitude.

Kessler syndrome isn't something that keeps me up at night.

~~~
ogre_magi
I see so many people around the Internet who smugly explain to their comments
section of choice what Kessler Syndrome is, and link the Wikipedia page for
it, and almost none of them actually know what they're talking about.

Whenever I bring up the density of debris in a given orbit, or the drag
characteristics of the debris, they get mad. Everyone should read your comment
and realize that it's possible to know a lot more about this than the
Wikipedia article tells you, and accept that they are not a special
enlightened environmentalist.

Kessler Syndrome is not a serious risk for Earth. It would be expensive and
difficult to cause a long-lasting debris field that made space launches
impossible _on purpose_. And we're trying to avoid it. Every organization with
access to space is taking steps to mitigate space junk, including CNSA.

~~~
Diederich
[https://en.wikipedia.org/wiki/Gravity_(2013_film)](https://en.wikipedia.org/wiki/Gravity_\(2013_film\))
doesn't help matters, though I did enjoy watching it overall.

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7000skeletons
There's a pretty great manga series (and an anime adaptation, though it's not
as good) called 'Planetes', that takes a pretty heavy focus on Kessler
Syndrome and humanity's attempts to grapple with it in the near-future. Worth
a read, if anyone's interested.

~~~
Namari
Didn't read the manga but the anime was pretty good.

~~~
7000skeletons
Honestly, I preferred the manga to the anime. Not to say that the latter is
bad, by any stretch of the imagination, but it did get a bit wild and off-the-
rails with it's final arc. The manga keeps things very grounded and
existential. Anyone who's ever worked a shitty job for menial pay with no
chance of advancement/further prospects will find something to relate to.

~~~
stcredzero
Also, nicotine withdrawal ("nic-fits") are severe enough to turn even the most
jaded working stiffs into a hero!

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mabbo
There's no incentive to me to make my satellite safely de-orbit before it gets
broken into pieces. So why would I bother? That's expensive.

But like all 'easy to litter, hard to clean up' problems of this nature, we
have a solution already: require a cleanup deposit ahead of time that will be
returned to whoever cleans it up.

All space-launching countries should sign an accord that said something along
the lines of "Every satellite must have a deposit to the international Kessler
Fund", say something like $X/kg, inflation adjusted. Companies would spring up
with the sole purpose of de-orbiting defunct satellites. Launch would become
more expensive, yes, but soon every bit of metal in space would come equipped
with a plan for how we're getting it out of orbit.

~~~
JshWright
This would work, but only if it allowed satellites to be exempted if they had
a credible plan for deoribiting (which the vast majority of satellites
launched today do, BTW). In that case, no one would actually pay the deposit,
since it would cost several orders of magnitude more to go "get" a satellite
(as opposed to just ensuring enough delta-V left over at the end of the
mission to deorbit)

~~~
ryandrake
Presumably, with OP’s plan, when you deorbit your own satellite you get your
deposit back.

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wycy
Kessler syndrome is why it was so irresponsible of the Chinese to blow up a
satellite just to prove that they could.

* [https://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_mi...](https://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_missile_test)

~~~
alex_duf
And irresponsible of the USA to send needles to space

[https://en.wikipedia.org/wiki/Project_West_Ford](https://en.wikipedia.org/wiki/Project_West_Ford)

~~~
delecti
A valid example, but not quite a fair comparison. One of those happened in
2007 and the other happened more than 15 years before the idea of "Kessler
syndrome" was even proposed.

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mrfusion
The weird thing about Kessler syndrome is that people use it as an argument
not to launch sattelites.

So it’s kind of like we’re getting the effects of Kessler syndrome by trying
to prevent it.

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Waterluvian
Satellites are a pretty big deal connercially. Maybe something like this would
just jumpstart one of our wildly productive bouts of human ingenuity?

Getting to the moon was kind of an insane idea until it happened. To someone
wholly uninformed, this feels like it could be similar.

~~~
Someone
[https://en.wikipedia.org/wiki/E.Deorbit](https://en.wikipedia.org/wiki/E.Deorbit):
_”e.Deorbit is a planned European Space Agency active space debris removal
mission developed as a part of their Clean Space initiative”_

[https://en.wikipedia.org/wiki/RemoveDEBRIS](https://en.wikipedia.org/wiki/RemoveDEBRIS):
_”RemoveDEBRIS is a satellite research project intending to demonstrate
various space debris removal technologies.

[…]

RemoveDEBRIS was launched aboard the SpaceX Dragon spacecraft on 2 April 2018

[…]

On 16 September 2018, it demonstrated its ability to use net to capture a
deployed simulated target.”_

------
CapitalistCartr
Orbital Debris Quarterly:

[https://orbitaldebris.jsc.nasa.gov/quarterly-
news/newsletter...](https://orbitaldebris.jsc.nasa.gov/quarterly-
news/newsletter.html)

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EADGBE
Humanity's always had a problem with it's trash.

Something I suppose we assume "space people" can deal with.

My suggestion: a space catapult (using a spring, not a weight).

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pbhjpbhj
Previously,
[https://news.ycombinator.com/item?id=16271434](https://news.ycombinator.com/item?id=16271434)
(9 months ago, 51 comments).

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mrfusion
One mitigating factor is that Objects in LEO would Deorbit pretty fast.
Usually in a matter of years. In higher orbits there’s a lot more space so
it’s not quite as bad.

Food for thought.

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0xcafecafe
I read about this first when I saw the movie "Gravity". I think if it really
becomes that bad, given enough resources mankind can solve it.

~~~
thinkcontext
It's a really hard problem. It costs over $100m to build and launch a
spacecraft. Then the spacecraft has to catch up to the piece of junk, then do
something to deal with the junk. We don't know what exactly it would do to
deal with the junk.

Then the spacecraft would have to catch up to another piece of junk. That's
hard because it's expensive in terms of fuel to change orbit. Thus the
spacecraft would only be able to deal with a very limited number of pieces of
junk before it ran out of fuel and became junk itself.

So, it would cost $millions per piece of junk. With hundreds of thousands now
and millions in a Kessler scenarios it would be fiendishly expensive.

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projectramo
Oh wow, is that where the term "Kessler Run" comes from in Star Wars?

If I recall, the Kessler run involved having to go through an asteroid field
in the recent Solo movie.

For fans, you may recall that in the original Star Wars Han says: "You've
never heard of the Millennium Falcon?…It's the ship that made the Kessler Run
in less than twelve parsecs."

This got ridiculed because parsec is a unit of distance not time, but in the
new movie they show that the run can be made longer or shorter.

~~~
Uehreka
Nah, that was called the Kessel run, and the parsec thing was an actual
mistake that they retconned in Solo.

~~~
projectramo
Oh, Kessel run!

I know they retconned it. Now they need to retcon the name so that it is
really Kessl run, short for Kessler.

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agumonkey
So climate change is about to be solved.

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user-x
Reminds me of Harry Potter in the Lestrange vault.

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throwawaynpc123
this is the point where we need to develop shields

~~~
Fordec
We have
[https://en.wikipedia.org/wiki/Whipple_shield](https://en.wikipedia.org/wiki/Whipple_shield)

~~~
throwawaynpc123
I meant energy shields

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squozzer
I guess we better get some people off this rock before earth orbit becomes
unnavigable.

~~~
Retric
That’s not on the table. You can clear LEO in minutes where satilites need
clear orbits over years to be useful.

Further, atmospheric drag keeps some orbits clear even in the worst case. The
problem is you then need to constantly burn some fuel to maintain orbit.

