Dust for space junk

I recall from Isaac Asimov's 6 CD collection (circa 1990), within it Space Exploration, that there were already 40,000 pieces of space debris in orbit. Replacing one panel due to microchip-triggered debris was a $50,000 repair, back then. Presumably now there's millions of little pieces. That's a lot of cleanup.

 

I was thinking that the energies of orbital speed impacts are greater than the molecular chemical bonds, so any sort of particles put up there for head-on or T-bone collision will at least partially gasify on impact, and leave equivalent craters on the target. One would want to keep craters small enough to not cause rapid target disassembly.

I'm not thinking of a low to mid orbital region that is exclusively junk. Thus, to prevent collateral damage, keeping this 'drag cloud' sub-orbital should be mandatory, not optional. That pretty much also means just one intended target per cloud.

It needs to slow the target only enough to cause perigee to dip into the upper atmosphere just enough to make it a relative short-timer. (Weeks or even months should be fine, prompt de-orbit is not essential.) The most effective or energy-efficient place to apply this is at the orbit's apogee.

But I don't have any decent ideas how to make a workable drag cloud.

I've long wondered about the possibility of a mal actor, intent on space terrorism, putting up a cloud of a few tons of sand or pea gravel in retrograde orbit.

 

Wouldn't a drag cloud effective enough the reduce orbital trash be in the way of rocket launches?

 

elon will figure it out

 

A sub-orbital cloud would fall into the atmosphere within the hour, and be gone. Only a malevolent actor would put one up in front of a launch.

An orbital cloud would be a problem for existing useful satellites as well as new launches.

 

All you have to do is tell him he can't do it.

Dot.gov should offer a bounty for reducing orbital debris...perhaps through a launch tax.
Or?
If they want to take the current approach that is being used by climate "science" they could go "space debris neutral" and just grind up a thousand pounds or so of aluminum and throw it into an incinerator before they launch.

 

I'm completely confident you understand carbon sequestration better than that.

 

maybe they can do something like the people cleaning up the ocean debris

 

Sure.
Carbon sequestration is when they plant a bunch of trees in a fire-prone state, during a 'mega-drought' just before a series of record fires.

...or did government funded radio LIE to me about that?

To be fair, trees - properly managed, "CAN" be a "net" carbon sink, but in reality it's a lot more complicated than just playing Johnny Appleseed with a bunch of loblolly pine saplings, and EOR - or East Of The Rockies, they actually "DO" sequester a lot of carbon this way.
HOWEVER (comma!) people do not often bother to properly assess the carbon throughput of a properly managed longleaf pine forest (Think: prescribed burning) OR ask WHY those trees got knocked down in the first place (Think: paper mills.)

It's like BEVs.
They're REALLY dirty to make, before they sorta get cleaner through economy of scale and (soon) renewables.
This is why if you try to assess the RO(c)I for BEVs you get a bunch of EVangelists lobbing insults and stat-grenades at you.

In the end?
There's NO shortcut to carbon capture.

You have to yank it out of the air (or, better, not put it there in the first place) and then figure out what to do with it.
Somebody thought of pumping it into the ground but then it was discovered that one of the more cost effective means of storing it would be to pump it into near-depleted oil fields, since they have to put it SOMEWHERE, and with oil fields you sorta have a convenient place to stuff it into, and all of the equipment there to begin with.
BUT - this inflamed the sensitivities of the "usual suspects."

 

Pumping it into basalt, where much of it rapidly solidifies into calcium carbonate (even on human timescales, not just geological timescales), is looking more reliable.

 

I'm here for that.

How about plucking it out of the air.
Has anybody done an energy budget?

 

Environmental impact statement?

 

Very high. Real numbers not at hand, but I seem to remember that "not releasing it in the first place" costs somewhere around 40% of the available energy of a fossil fuel. It seems difficult for "plucking it out of the air" methods to match that, but different paths may exist.

Someone here (@tochatihu ??) has mentioned some sort of work or theory about adding pulverized basalt to agricultural soils, so that it can take up CO2 directly from the air, bypassing the energy-intensive capture and deep injection steps. I haven't noticed any followup work or discussion.

Natural erosion exposing fresh rock to the atmosphere does some of this too, but not at the rates we need.

 

Oh, hi. There are several recent publications on mineral carbonation. Beerling, Manning, Renforth are 3 names and if your search begins with those you will not miss much hot stuff. It is a matter of putting rocks with Ca and Mg (but not yet CO2) in a setting where they can 'carbonate' at good speed. That term seems poorly chosen, but if authors and readers agree on a local meaning, OK then.

If the rocks you want are not laying about, digging is required. If not where you want, transport is required. Grind is always required it seems. All those requireds have energy (thus CO2) costs, 'fueling' LCA and ROI studies.

Concrete structures absorb CO2 in the same way. They have little surface area per ton (or per whatever), so it is convenient that 'somebody else' knocks them down and increases surface areas. We know the retirement rate of concrete structures (particularly rapid in China), and burying all that could capture ~1/10 of a petagram CO2-C per year. But as I have recently learned built concrete structures do 'carbonate', just standing there, to a mm (or few) depth per year. This limits the bang associated with concrete-burial buck.

CarbFix in Iceland makes holes into basalt and injects CO2. Which they have captured and concentrated out of air, but a geothermal power plant is handy, so that energy requirement lacks a CO2 cost. Check their website to see how many tons CO2 they have stowed away. It works well there, but in a quite unusual geological setting.

Direct air capture of CO2 has in recent years fallen from ~USD$1000 to ~USD$100 per ton of CO2. One gang says they can do it for $50. Maybe. This one can set up and do anywhere, but best choose a place where some use can be made of the CO2.

==
Growing trees is fine, but few situations rapidly increase soil organic carbon. Things built from wood can sequester carbon for a long time - better if your town has a fire dept. and not many termites.

There are also other ways to increase soil organic carbon.

 

"Carbon sequestration is when they plant a bunch of trees in a fire-prone state ..." #11

As this is PriusChat after all, data-free cheap shots should be allowed, and may even serve to stimulate thoughtful consideration.

Such as, have any planted-for-carbon-capture forests actually burned yet? No news popped up immediately, but I'll tell you who ought to know:

Growing trees – and capturing carbon | US Forest Service

Which mentions Grant Domke. Just email him and ask the Q. He is a federal employee, works for you, and is a central figure in US reforestation. He would know about Lolo/Montana and all the rest of it.

But may I tell you what not to ask him? The actual locations of 130,000 FIA plots mentioned in the links. Those are secret, baby! (No I don't know either ) It's a bit funny actually.

==
In perhaps a less well-organized effort, pines have recently been planted in large areas of Yunnan Province. For carbon, soil-erosion control, and many other good intentions. Recent droughts have cooked some of those, and it would actually be possible to use time series satellite imagery to quantify that cook. Has not been done, but could be.

Won't be done by me. If I were to "knat eht fo tnorf ni dnats" (read that backwards ) it would be to suggest better ways to reforest than to plug in monospecific, ill-chosen, narrow-canopy*, wrong pines. Some local dudes want me to work with them on such.

--
*narrow-canopy means sunlight reaches the ground between trees, grasses grow, and they might as well be matchsticks.

 

how many holes have been punched through our manned space craft ?

through astronauts suits?

through fuel tanks ?

weird, I thought if stuff was flying 50-150000 mph in all different orbits and directions, we would see that by now.

guess it's not a big deal after all

 

Not until it's YOUR spacecraft....or suit.

There's a principle in warfare called 'big sky, little bullet.' and space is VERY aptly named.
There's a LOT of it up there.
However (comma!!)
There's a lot of stuff up there TOO, and if you know anything about why "launch windows" are a thing you'll understand how and why orbital debris are a thing.
Nations that launch stuff are 'supposed' to have a plan for cleaning up their litter, either dynamically, or letting Isaac do it.
However....sometimes bad actors...aren't acting.

It's sorta like atmospheric nuclear testing.
Everybody used to do it.
Nobody does it now.....or at least they not "SUPPOSED" to...

When "news" is carefully managed and narrowly focused, it might be hard to tell.
The ChiComms may not be the ONLY ones who do that, you know.

I was listening to government funded radio the other week and I caught a squib....JUST one little comment about wildfires in the other 'PRC' burning up some sequestered carbon. I never caught any echoes of that tiny little 'pop' in the news, and so.....I s'pose it 'never happened.'
OTHERWISE it would be in the "news", riiiight?
BTW.....if government funds 'public radio' @ an insignificant, eensy-weensie little 4% as a line item in the budget...then they fund churches and oil companies @ 0%
'cause.....they're not in the budget, riiiight?

'science and DATA.....'

 

An impact crater on one of the windows of the Space Shuttle Challenger following a collision with a paint chip during STS-7. (1983)



See also https://en.wikipedia.org/wiki/2009_satellite_collision

Does anyone know right away how many impacts were found on LDEF? A quick skim finds the number was "large", but details appear hidden behind a paywall. Another article mentions a survey of Hubble Space Telescope solar panels that were swapped out:

We don't have similar reports for the many satellites that just quit working, but are never repaired or retrieved.

I should more time for a better search later.

===========
Edit: some more added.

HST:
"Observed crater sizes range from about 2 μm to 6–7 mm. On the HST solar array impact fluxes at the same crater pit diameter are higher than for EURECA for sizes exceeding about 200 μm while they are comparable for smaller sizes. Impact fluxes on EURECA and HST do both exceed the 6 face averaged fluxes on LDEF."

EURECA:

"The main findings of the detailed visual survey of Eureca's external surfaces can be summarized as follows:

• There was no functional failure on Eureca that could be related to an impact

• On the front sides of the solar arrays, more than 1000 impact features can be seen with the naked eye

• 71 impact punctures in the outer layer of the thermal blankets were detected on the main spacecraft body (non-penetrating impacts Three impacts were found on the ESA logo plate and 11 more on the scuff plates

• The impact features identified range in size from 100 microns to several millimeters. The largest crater diameter on the solar arrays is 6.4 mm. The largest feature on the main body is a 2 mm hole in the ESA/ERNO logo plate

• A surprisingly high proportion of the impacts on the solar-cell cover glasses - about 30% - show signs of directionality by having a non-spherical crater shape."