Harpoon space junk?

I was a little perplexed by an item on the news the other day about a plan
to fly a harpoon based device to bring down space junk. Surely this cannot
work. I mean not unless you fly a spacecraft for every bit of sizable junk
up there, risking more junk being created by the launches system.

Brian

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My feeling is based on what happened during tethered experiments back a long
time ago. the effect seemed to end in chaotic tumbling and collisions which
could easily liberate more junk, but smaller and hence less easy to spot.


My idea of a space junk remover would be to try two ideas. firstly, a large
but superstorng sail is deployed so that the junk is captured, then the
edges are sent via small thrusters so they cross over and capture the
object. then you could deorbit the whole thing assuming you coule still get
the main thrusters to point in the right direction!

The second way of course would never be allowed.
Simply navigate a nuke neear each object and vaporise it all.


Brian

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"JF Mezei" wrote in message
b.com...
On 13-04-23 02:29, Brian Gaff wrote:
I was a little perplexed by an item on the news the other day about a
plan
to fly a harpoon based device to bring down space junk.

They need a vacuum cleaner for that :-)

Out of curiosity, what if they were to release air at a certain altitude
with orbital velocity. Wouldn't that air remain in orbit ?

And any space debris passing through it would experience drag and slow
down.

A harpoon system might be interesting with the right type of software
and multiple harpoons in different directions.

Launch it in one orbital plane. If you know the exaxt orbital
characteristics of one object, you can program the "vacuum cleaner" to
aim one harppon and launch it such that it will hit the space debris
flying in a different orbit. Assuming strong enough rope between the
harpoon and the vacuum cleaner, the linking of the 2 objects would cause
their orbits to "meld". Once new orbit is establishe, the vacuum cleaer
then aims for another space debris, launches at just the right time to
harpoon it and now, you have 3 objects whose orbits have to meld/join.
newton at work probaby pretty violently too.

Once the vacuum cleaner has launched all its harpoons, it fires de-orbit
engine and ropes all the captured debris down to atmosphere with it.

JF Mezei formuleerde op dinsdag :
On 13-04-23 02:29, Brian Gaff wrote:
I was a little perplexed by an item on the news the other day about a plan
to fly a harpoon based device to bring down space junk.

They need a vacuum cleaner for that :-)
Would that work in space (in a vacuum environment)?

"Andre"; "PE1PQX" wrote in message
...

JF Mezei formuleerde op dinsdag :
On 13-04-23 02:29, Brian Gaff wrote:
I was a little perplexed by an item on the news the other day about a
plan to fly a harpoon based device to bring down space junk.

They need a vacuum cleaner for that :-)
Would that work in space (in a vacuum environment)?


Umm no. Hence the smiley.

However, the reverse might. An air-puffer to slow down the target a bit and
lower its orbit.





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Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

Of course not, but I think what was meant was some kind of attraction being
used. I doubt there is much of a ferrous nature in much of the junk either
though.


I was also wondering if water might be able to be used to make the item
less stable in some way. However all the various systems I've seen
described have a high price tag. Ideally you need a device that can not only
change orbits, but inclination and can refuel as well. I envisage a long
term project using a fleet of spacecrafte with ion propulsion.
Actually dealing with the smaller debris is more challenging though.

Brian

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Andre; "PE1PQX" wrote in message
...
JF Mezei formuleerde op dinsdag :
On 13-04-23 02:29, Brian Gaff wrote:
I was a little perplexed by an item on the news the other day about a
plan to fly a harpoon based device to bring down space junk.

They need a vacuum cleaner for that :-)
Would that work in space (in a vacuum environment)?

The problem is that as we all know every action has an equal and opposite
reaction.

Would thermite burn in a vacuum?

Brian

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Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
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"Greg (Strider) Moore" wrote in message
...

"Andre"; "PE1PQX" wrote in message
...

JF Mezei formuleerde op dinsdag :
On 13-04-23 02:29, Brian Gaff wrote:
I was a little perplexed by an item on the news the other day about a
plan to fly a harpoon based device to bring down space junk.

They need a vacuum cleaner for that :-)
Would that work in space (in a vacuum environment)?


Umm no. Hence the smiley.

However, the reverse might. An air-puffer to slow down the target a bit
and lower its orbit.





--
Greg D. Moore
http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

Brian Gaff stelde de volgende uitleg voor :
The problem is that as we all know every action has an equal and opposite
reaction.

Would thermite burn in a vacuum?

Brian

If it requires O2 from the surrounding environment, then no.. But I am
not a chemist...

Sounds a bit frightening and prone to nasty accidents to me.


Besides the speed the bigger masses are moving at would need one heck of a
strong cable to keep tethered together, and any elasticity could mean they
collide and disintigrate giving rise to more smaller bits of junk.




Brian

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From the Sofa of Brian Gaff Reply address is active
"JF Mezei" wrote in message
eb.com...
On 13-04-24 03:19, Brian Gaff wrote:

described have a high price tag. Ideally you need a device that can not
only
change orbits, but inclination and can refuel as well.

But If you have a harpoon and a good coputer, you don't need to be in
the same orbit. You just target a piece of debris and launch harpoon in
the right direction at the right time so it hits the piece of debris as
it flies by in different direction/altitude. Once grappled, let Newton
do the rest.

The combo harpoon and debris now have a new combined orbit. Harpoon can
now recalculate when to launch another harpoon to grapple another piece
of debris that will pass by. etc etc

In sci.space.station message , Tue, 23 Apr
2013 13:30:37, Brian Gaff posted:


My idea of a space junk remover would be to try two ideas. firstly, a large
but superstorng sail is deployed so that the junk is captured, then the
edges are sent via small thrusters so they cross over and capture the
object. then you could deorbit the whole thing assuming you coule still get
the main thrusters to point in the right direction!

No sheet of material can be string enough to capture something impacting
at over the speed of sound in that material, since it cannot resist fast
enough. Approximately.


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In sci.space.station message , Wed, 24
Apr 2013 13:18:49, Andre posted:

Brian Gaff stelde de volgende uitleg voor :
The problem is that as we all know every action has an equal and
opposite reaction.

Would thermite burn in a vacuum?

Brian

If it requires O2 from the surrounding environment, then no.. But I am
not a chemist...


Then why answer?

Brian, it will.

Earlier, for "string" read "strong".

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