$5M Moon Rock Stolen From Malta Museum

Doug... wrote in message ...
Ummmm... OK, I'm not visualizing the setup very well, here. For a
tether to drop straight down from an orbiting craft, that craft would
have to be in selenosynchronous orbit, wouldn't it? And 20 km is a LOT
less than the height of a SSO, isn't it?

From a vehicle orbiting 20 km above the surface of the Moon, how do you
propose to completely null out the orbital vehicle's velocity from the
scoop end of the tether?

We are talking about a rotating space tether. It is rotating
in the plane of its orbit with the part closer to the moon going
backwards relative to the orbital motion. Say the orbital motion
is 1.6 km/sec and the tip speed is 1.6 km/sec, so near the surface
of the moon these cancle. On the high side they add together, so
the tether can pickup something down low and then toss it fast up high.

It does not drop exactly straight down, but for a guy sitting on
the moon who only sees it when it is nearby it will mostly
seem to be coming down from one side and then going up the
other.

This general idea is called a "momentum exchange tether". You
will also hear "bolo" and "rotovator" with rotovator being the
case that touches a moon/planet. I like "rotating tether" as
it seems clearer. See:

http://tethers.com/MXTethers.html

My simulator is a Java applet, so it should be easy to run.
You can just click on samples and run them to help you
visualize what is going on. It is at:

http://spacetethers.com/spacetethers.html

-- Vince

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~
Vincent Cate Space Tether Enthusiast
http://spacetethers.com/
Anguilla, East Caribbean http://offshore.ai/vince
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~

You have to take life as it happens, but you should try to make it
happen the way you want to take it. - German Proverb

In sci.space.policy Vincent Cate wrote:
(Terry Goodrich) wrote in message . com...
Please don't loose track that we are trying to just get 20 kilo or so
of moon rocks to sell to collectors, not mine the moon. While I can
see the value of developing tethers and ion drives for a long term
project (I have a lot of interest in ion and vasmir drives), I don't
believe we have a budjet for any heavy duty R&D ($400~500 million).

You might only want 20 kg, but some of us want more. I think people
would buy much more than 20 kg of moon rocks at a price that
permits a good profit if you use tethers. If you could get more
than 20 kg of diamonds, you would not want to?

Depending on whetever getting them would require going to an unkown
and anproven technology for which you not just can't really get
proven materials but also you need to do a many orders of magnitude
higher up-front investment. For initial profit based missions, tethers
simply don't enter into the picture.


Ion drives are standard options on GEO sats these days (and I
expect most use some kind of electric propulsion for station keeping).

I don't think it would cost $400 to $500 mil, but it is clearly
hard to say.

SMART-1 cost $100m. Its a small orbiter and was launched as a add-on
cargo on a flight where most of the expenditure was paid for by other
satellites. You are going to need the full capacity of a heavy launcher,
so $150 - $180m. Assuming that whatever you are launching cost you $200m
to develop and build is reasonable and you co-incidentialy have arrived
at $400m.


To me it seems much easier to justify an investment if you end up
with a low ongoing cost and 100 kg a month than a deal with a
onetime payback of 20 kg.

Really? have you tried writing this up? How much mass doyou need to launch
and how much does the thing launched cost? And please use realistic present
day costs and not arbitrarily tweaked numbers until it worked for you.


-- Vince

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~
Vincent Cate Space Tether Enthusiast
http://spacetethers.com/
Anguilla, East Caribbean http://offshore.ai/vince
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~

You have to take life as it happens, but you should try to make it
happen the way you want to take it. - German Proverb

--
Sander

+++ Out of cheese error +++

"Sander Vesik" wrote in message
...
In sci.space.policy johnhare wrote:

"Dick Morris" wrote in message
...


Vincent Cate wrote:
On the other hand there is not so much room for improvement in
rockets.

There's not a lot of room for improvements in efficiency (Isp), but
we've barely scratched the surface as far as cost reduction is
concerned.

Come on now, rockets have been under continous development
for most of a century. There can't be very many ways to improve
engines with that much history. What could you possibly do to
improve them. Are you willing to say that they are not near
perfection now? :-)


Lets look at cars and move back... lets say 10 years. Cars and their
engines have been around and well studied in a much more competitive
environment than rockets for more than 100 years. would you say that
there are no real improvements to be made in the next 10 years?

cars being made now are quite a bit more efficent than those made 10
years ago.

The fuses in your sarcasm detector are burned out. Put it in the shop
for repairs at once. FWIW, a better analogy is firearms. After half a
millenia, the muzzle loader would have been understood by the earliest
practitioners of the art. The next century saw the introduction of
repeating rifles, breach loading cannon, machine guns, autoloading
cannon, assault guns, GPS rounds, etc. None of which resembled
the earlier era in weaponry.
--
Sander

+++ Out of cheese error +++

Henry Spencer wrote:
Also, there's rad-hard and there's rad-hard. Electronic gear that
can take modest amounts of radiation is not hard to find. But a
slow passage through the inner Van Allen belt is a whole new order
of magnitude.

Use vacuum tubes.

If all this is about bringing back moon rocks for sale, I think the
bottom would drop out of that market fairly quickly. A handful of
multi-millionaires would be willing to play plenty to have the first
privately owned moonrock. Maybe the second or third. But who would
buy the ten thousandth, for any price at all? Maybe for one dollar,
or other souvenir shop chump change.
--
Keith F. Lynch - http://keithlynch.net/
Please see http://keithlynch.net/email.html before emailing me.

In article ,
Keith F. Lynch wrote:
Also, there's rad-hard and there's rad-hard. Electronic gear that
can take modest amounts of radiation is not hard to find. But a
slow passage through the inner Van Allen belt is a whole new order
of magnitude.

Use vacuum tubes.

Not practical for complex systems that want long life and high reliability
with zero maintenance. There's a reason why the military was willing to
pay outlandish prices for early transistors to get the vacuum tubes out of
missiles and aircraft. There were air-defence interceptors whose radars
and computers were built with vacuum tubes... but a lot of the time they
were supposed to spend in the air was actually spent in the maintenance
hangar, surrounded by cursing electronics technicians.

(Yes, there are vaporware micro-tube technologies that claim to solve this.
There are also vaporware ultra-rad-hard semiconductor technologies. You
can't actually *buy* either one in operational form.)

If all this is about bringing back moon rocks for sale, I think the
bottom would drop out of that market fairly quickly. A handful of
multi-millionaires would be willing to play plenty to have the first
privately owned moonrock.

There are already privately-owned moon rocks. Yes, legitimate ones: some
of the verified lunar meteorites are in private hands.

In practice, the market you want is more substantial numbers of people
willing to pay significant, but not ridiculous, sums for lunar souvenirs.
(There are professional meteorite dealers who will pay quite high prices
for a verified lunar meteorite, in anticipation of subdividing it for
resale.) Milking the market efficiently requires that you *not* dump
huge amounts, but rather ramp up the supply gradually, keeping the prices
up at the edge of pain while slowly expanding the audience.

Managed well, the market is significant. Whether it's big enough to pay
for major development projects is another question.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

Sander Vesik wrote in message ...
Depending on whetever getting them would require going to an unkown
and anproven technology for which you not just can't really get
proven materials but also you need to do a many orders of magnitude
higher up-front investment.

The main material is Spectra-2000. This is a well proven fishing-line
and kite-line material.

Because a tether system can be so much smaller, it should not be
orders of magnitude more investment.

For initial profit based missions, tethers
simply don't enter into the picture.

Time will tell.

Vince:
I don't think it would cost $400 to $500 mil, but it is clearly
hard to say.

SMART-1 cost $100m. Its a small orbiter and was launched as a add-on
cargo on a flight where most of the expenditure was paid for by other
satellites. You are going to need the full capacity of a heavy launcher,
so $150 - $180m. Assuming that whatever you are launching cost you $200m
to develop and build is reasonable and you co-incidentialy have arrived
at $400m.

There is some reason to believe that if a government organization can
do something for $100 mil that a new startup company could do it for
much less.

The Falcon-V will take 10,000 lbs to LEO for $12 mil. This should be
enough for a probe using a tether. We do not need a $150+ mil launcher.
It is the all chemical rocket approach that need lots of starting mass.

To me it seems much easier to justify an investment if you end up
with a low ongoing cost and 100 kg a month than a deal with a
onetime payback of 20 kg.

Really? have you tried writing this up? How much mass doyou need to launch
and how much does the thing launched cost? And please use realistic present
day costs and not arbitrarily tweaked numbers until it worked for you.

As I said about costs above, "... it is clearly hard to say". But a tether
to lift 5 Kg from the moon only needs to be like 15 to 30 Kg.
So the system does not need to be really huge.

-- Vince

"Paul Blay" wrote in message ...
According to randomme Google search there's 382 kg of moon rock on
Earth - which _isn't_ for sale. Just how fast do you think the purported
"$5 million" for a few grams will drop if 20 kg are dropped on the market?
If that 20 is doubled to 40 it is far from guaranteed that the _value_ will
also double.

Of course the price will be much lower when there is a real supply.
I think we could go from a million per gram to a thousand per gram
real fast. Random meteors sell for around $100/gram. When you
sell moon rocks you could include a video of when you picked them
up, so I think they will always be worth more than meteors. Imagine
that one company using tethers has sent back 2,000 Kg and that another
company using all chemical rockets has sent back 20 Kg, which one
do you wish you had shares in?

If you actually got $1,000/gram for 2,000 Kg that would be
$2 bil. So even $250/gram and $500 mil might not be bad
for the tether guy. But that price would clearly bankrupt
the non-tether guy.

-- Vince

"Vincent Cate" wrote ...
"Paul Blay" wrote ...
According to randomme Google search there's 382 kg of moon rock on
Earth - which _isn't_ for sale. Just how fast do you think the purported
"$5 million" for a few grams will drop if 20 kg are dropped on the market?
If that 20 is doubled to 40 it is far from guaranteed that the _value_ will
also double.

Imagine
that one company using tethers has sent back 2,000 Kg and that another
company using all chemical rockets has sent back 20 Kg, which one
do you wish you had shares in?

The one that did it _first_. ;-)

In sci.space.policy Vincent Cate wrote:
Sander Vesik wrote in message ...
Depending on whetever getting them would require going to an unkown
and anproven technology for which you not just can't really get
proven materials but also you need to do a many orders of magnitude
higher up-front investment.

The main material is Spectra-2000. This is a well proven fishing-line
and kite-line material.

Because a tether system can be so much smaller, it should not be
orders of magnitude more investment.

"should nbot be" without numbers is not worth much.


For initial profit based missions, tethers
simply don't enter into the picture.

Time will tell.

Vince:
I don't think it would cost $400 to $500 mil, but it is clearly
hard to say.

SMART-1 cost $100m. Its a small orbiter and was launched as a add-on
cargo on a flight where most of the expenditure was paid for by other
satellites. You are going to need the full capacity of a heavy launcher,
so $150 - $180m. Assuming that whatever you are launching cost you $200m
to develop and build is reasonable and you co-incidentialy have arrived
at $400m.

There is some reason to believe that if a government organization can
do something for $100 mil that a new startup company could do it for
much less.

Provided it does not have to work, yes. If it does have to work, it becomes
much less clear, esp as they will have to fly a lot of micro/nanosats
to get the basic know-how and technology. Never mind that they will also
have to figure out the descent and return side (SMART-1 is orbiter).


The Falcon-V will take 10,000 lbs to LEO for $12 mil. This should be
enough for a probe using a tether. We do not need a $150+ mil launcher.
It is the all chemical rocket approach that need lots of starting mass.

I will believe that when it has launched at least once. And of course, the
$150m launcher puts rather more than 10k lbs in LEO. Doing a lunar return with
that small amount of mass from *LEO* will be tricky.


To me it seems much easier to justify an investment if you end up
with a low ongoing cost and 100 kg a month than a deal with a
onetime payback of 20 kg.

Really? have you tried writing this up? How much mass doyou need to launch
and how much does the thing launched cost? And please use realistic present
day costs and not arbitrarily tweaked numbers until it worked for you.

As I said about costs above, "... it is clearly hard to say". But a tether
to lift 5 Kg from the moon only needs to be like 15 to 30 Kg.
So the system does not need to be really huge.

Maybe you should start doing some numbers then? Like say how much a 100 km
spool would weight?


-- Vince

--
Sander

+++ Out of cheese error +++

In sci.space.policy Paul Blay wrote:
"Vincent Cate" wrote ...
"Paul Blay" wrote ...
According to randomme Google search there's 382 kg of moon rock on
Earth - which _isn't_ for sale. Just how fast do you think the purported
"$5 million" for a few grams will drop if 20 kg are dropped on the market?
If that 20 is doubled to 40 it is far from guaranteed that the _value_ will
also double.

Imagine
that one company using tethers has sent back 2,000 Kg and that another
company using all chemical rockets has sent back 20 Kg, which one
do you wish you had shares in?

The one that did it _first_. ;-)

yes, being first - never mind the technology (and to an extent,
expenditure - will be the winner. Chances are good they can buy
the competition out. At the very least they can undercut competition
and make sure they go under.

In business, technology is more often than not irrelevant.

--
Sander

+++ Out of cheese error +++