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Space junk

Started by Live2Learn, December 15, 2017, 12:04:40 AM

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Live2Learn

Space junk amount & hazard to Com/Nav satellites may be severely underestimated.  http://physicsworld.com/cws/article/news/2017/dec/11/space-debris-threat-to-geosynchronous-satellites-has-been-drastically-underestimated

Lotsa interesting implications for GPS, and dependent equipment.

PHall

The GPS birds are in a lower orbit where's a LOT of space junk around. One of the reasons they have on-orbit spare satellites.

ColonelJack

Well, if you listen to the "Flat Earth" group, there's nothing up there at all.  (How they can refute in-your-face science is beyond me.)

Jack
Jack Bagley, Ed. D.
Lt. Col., CAP (now inactive)
Gill Robb Wilson Award No. 1366, 29 Nov 1991
Admiral, Great Navy of the State of Nebraska
Honorary Admiral, Navy of the Republic of Molossia

vorteks

Quote
...all in the industry need to ensure that effective mitigation measures are implemented to avoid placing the entire market for GEO-based satellite services at risk

Mitigation measures such as......what? Article doesn't get into it.

Live2Learn

Quote from: vorteks on December 15, 2017, 02:29:26 PM
Quote
...all in the industry need to ensure that effective mitigation measures are implemented to avoid placing the entire market for GEO-based satellite services at risk

Mitigation measures such as......what? Article doesn't get into it.

I'd guess "mitigation measures" are firmly planted in the "TBD" category.  However these unknown and likely highly speculative measures might be funded, operated, and be coordinated with all of the internationally competing interests is a tough question.  IOW, "lotsa luck" on a quick fix to the bourgeoning problem.  :)   That, and keep pilotage & VOR skills current.   

Spam

This has been a recognized threat for decades.

Go read the Ben Bova "Kinsman" SF books (70s/80s). He had clean up of the low to mid orbitals as a strategic space access mission of the US Space Force. Locate>track>monitor>assess threat>mitigate by planning>mitigate by on-orbit adjustment burns and deorbiting of large items.

(MAN we shoulda had a permanent off-planet presence by now)!

V/r
Spam



Spam

As to specific measures, consider:

1. Mitigate risk by Planning. Don't put payloads into threatened orbits with high impact potential. Select and insert into selections which optimize likelihood of impacts vs. coverage over time.

2. Mitigate risk by Design. Assess vulnerability against the threat at your selected orbitals, and design for survivability (single hit, multi hit, prox, rad, etc.). Got a copy of the R.E. Ball book "Combat survivability analysis and design" on the table here in my office... same basic principles of shot line analysis and designing for graceful degradation, etc. Consider that some payloads have been considering this for decades already (hardening).

3. Mitigate risk by Control. This can include sending either manned (like in "Kinsman") or unmanned (preferably) craft to deorbit chunks of debris or nudge them into safer orbits. It need not be space based, though. Consider the potential for the use of directed energy to heat/ablate a surface of an object to perform the same task: sustained outgassing, over a long baseline, can produce a significant vector product.


The worst thing you could do, probably, is yet another demo of being able to "shoot down" an object, which (as the Chinese and US forces have each demonstrated) just magnifies the problem. There are many people working these issues in the systems effectiveness and survivability/vulnerability communities, as they are with many things brought up here (e.g. the UAVs on the White House thread from a couple of years ago).


I'm surprised no one has made a WALL-E space junk reference yet.


R/s
Spam


vorteks

Was thinking more along the lines of installing sloped armor on the sats.  8)

stillamarine

Quote from: Spam on December 15, 2017, 06:59:26 PM
This has been a recognized threat for decades.

Go read the Ben Bova "Kinsman" SF books (70s/80s). He had clean up of the low to mid orbitals as a strategic space access mission of the US Space Force. Locate>track>monitor>assess threat>mitigate by planning>mitigate by on-orbit adjustment burns and deorbiting of large items.

(MAN we shoulda had a permanent off-planet presence by now)!

V/r
Spam

It always saddens me when I watch an old movie from my younger days that is supposed to be in the high tech fancy future......but we are already past the date in the movie........
Tim Gardiner, 1st LT, CAP

USMC AD 1996-2001
USMCR    2001-2005  Admiral, Great State of Nebraska Navy  MS, MO, UDF
tim.gardiner@gmail.com

N6RVT

Quote from: vorteks on December 15, 2017, 07:59:15 PM
Was thinking more along the lines of installing sloped armor on the sats.  8)
If the junk is coming the other way thats a 36,000 MPH collision.  It would take a Saturn V to launch a satellite with enough armor to help - and then the collision would probably send it down in flames or off into space to join Voyager.

PHall

Quote from: N6RVT on December 15, 2017, 08:48:40 PM
Quote from: vorteks on December 15, 2017, 07:59:15 PM
Was thinking more along the lines of installing sloped armor on the sats.  8)
If the junk is coming the other way thats a 36,000 MPH collision.  It would take a Saturn V to launch a satellite with enough armor to help - and then the collision would probably send it down in flames or off into space to join Voyager.

At 36,000mph even a paint flake will cause serious damage. The Laws of Physics are pretty much the same even in Microgravity.

SarDragon

Kinetic energy is equal to 1/2 the product of the mass and the square of the speed. In formula form: Ek=1/2m*v^2

Even small things traveling really fast have a lot of energy. According to my calculations, a 1 gram particle, traveling at 36,000 mph has the same energy as a 3000 pound car traveling at 975 mph.
Dave Bowles
Maj, CAP
AT1, USN Retired
50 Year Member
Mitchell Award (unnumbered)
C/WO, CAP, Ret

PHall

Quote from: SarDragon on December 16, 2017, 03:54:40 AM
Kinetic energy is equal to 1/2 the product of the mass and the square of the speed. In formula form: Ek=1/2m*v^2

Even small things traveling really fast have a lot of energy. According to my calculations, a 1 gram particle, traveling at 36,000 mph has the same energy as a 3000 pound car traveling at 975 mph.

The shuttles had chips out of their windshields that NASA said were caused by paint flakes impacting at 36,000 mph.

Live2Learn

Quote from: SarDragon on December 16, 2017, 03:54:40 AM
Kinetic energy is equal to 1/2 the product of the mass and the square of the speed. In formula form: Ek=1/2m*v^2

Even small things traveling really fast have a lot of energy. According to my calculations, a 1 gram particle, traveling at 36,000 mph has the same energy as a 3000 pound car traveling at 975 mph.

Physics is stark.   We better not retire the VOR network.  No, not 'til there's a solid work around to physics.

SarDragon

Quote from: PHall on December 16, 2017, 04:06:29 AM
Quote from: SarDragon on December 16, 2017, 03:54:40 AM
Kinetic energy is equal to 1/2 the product of the mass and the square of the speed. In formula form: Ek=1/2m*v^2

Even small things traveling really fast have a lot of energy. According to my calculations, a 1 gram particle, traveling at 36,000 mph has the same energy as a 3000 pound car traveling at 975 mph.

The shuttles had chips out of their windshields that NASA said were caused by paint flakes impacting at 36,000 mph.

No argument there.
Dave Bowles
Maj, CAP
AT1, USN Retired
50 Year Member
Mitchell Award (unnumbered)
C/WO, CAP, Ret

Spam

Quote from: SarDragon on December 16, 2017, 04:09:26 AM
Quote from: PHall on December 16, 2017, 04:06:29 AM
Quote from: SarDragon on December 16, 2017, 03:54:40 AM
Kinetic energy is equal to 1/2 the product of the mass and the square of the speed. In formula form: Ek=1/2m*v^2

Even small things traveling really fast have a lot of energy. According to my calculations, a 1 gram particle, traveling at 36,000 mph has the same energy as a 3000 pound car traveling at 975 mph.

The shuttles had chips out of their windshields that NASA said were caused by paint flakes impacting at 36,000 mph.

No argument there.


Seriously!  Back when I was 19 - 20 I was working as a tech for McDonnell to pay for my BS degree (on the PGOC contract, payload ground ops) and was up on the white floor in OPF2 (I think it was) and they took me over and showed me a dime sized star crack apparently caused by a micrometeor. They said that the thing (looked like what you get on your windshield from a rock on the freeway) probably was a paint fleck sized bit of dust. Can't remember what orbiter it was, though. Probably the "Orbiter from Hell" (Columbia)... everything bad happened to it.

IIRC there was a payload which was orbited for a couple of years in the 80s just to test micrometeor and vacuum and rad damage. Long Duration Exposure Satellite or Facility or something. It was a horizontally integrated payload in the OPF before I started at KSC, though.

V/r
Spam

PS Live2Learn: thanks much! This is an interesting post and discussion.


Live2Learn

#16
 :'(Maybe, rather than fighting cell towers and band issues, we might embrace them as a nearly complete coverage, geo-referenced ground network for 'alternate nav' purposes.  That would perhaps be less expensive than installing 'every woman's intertial guidance units (IGU)' in the 250 K aircraft in the US.  If ADS/B take 2 included an IGU lat/long data burst we'd perhaps receive the same real tiem, in-cockpit position data as from our current ADS/B 'in' boxes and space junk would be irrelevant (for that application).  We might even get wx, Sunday morning cartoons, and music!  With AI and onboard celestial nav tools the very fragile nav constellation would, perhaps, become irrelevant as ( last I heard) celestial navigation, like paper charts, is unhacable.  NASA published a very interesting, unclassified verson of a much more detailed threat analysis of GPS several years ago.  FWIW, after reading it I wondered about the bureaucratic inertia that kept satellite based reference technology firmly in place as the 'nav system for the future.  It looks to me like the FAA decision makers for ADS/B and their supporting staff ignored, dismissed, or were unaware of the inherent fragility of their fundamental technology.  Just my casual and very humble opinion, of course.  :(