Once We Have A Self Sustaining Mars Colony - Then What?

General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7. This exceeds escape velocity of the moon already. In the vacuum of space or the near vacuum of Mars such a system easily achieves muzzle speeds 3x higher. These permit projectiles to travel between worlds at very low cost.

Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets. Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.

30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.

This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.

So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.

In article ,
says...

General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7. This exceeds escape velocity of the moon already. In the vacuum of space or the near vacuum of Mars such a system easily achieves muzzle speeds 3x higher. These permit projectiles to travel between worlds at very low cost.

Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets. Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.

30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.

This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.

So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.

This all sounds quite unaffordable compared to utilizing the resources
we have here on earth.

Also, once you shoot these things at earth, how do you propose to get
them safely to the surface?

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

William Mook wrote:


General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7.


No, it doesn't. Try 10 rounds per minute and even that isn't working
yet at those kinds of rates for long because of heat issues and rail
erosion and ablation.


Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets.


Yes, it's a little tiny lightweight projectile.


Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.


Handwavium. MEMS rockets deliver only small amounts of thrust (hence
'MEMS'). You can't just paste a zillion of them on something and
multiply. You have now also added heavy insulated tanks to your
'cheap carrier'. You can't go solid fuel because you need to be able
to turn them on and off. The only liquid fuel MEMS rockets I've seen
anyone talking about use hydrogen peroxide, not deeply cryogenic fuels
(although feel free to cite such an engine) and they only manage tiny
amounts of thrust. Their thrust/weight ratios are high, but that
rapidly goes to **** once you start adding plumbing, tanks, multiple
engines, etc.


30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.


Now divide your numbers by 180 for a realistic firing rate, deduct the
weight of all the extra **** you have to put on the round for
midcourse corrections and surviving reentry, and adopt a realistic
maintenance cycle for your equipment.


This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.


Yeah, because I WANT projectiles doing interplanetary speeds slamming
into my house.


So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.


No reason unless you live in the real world and aren't allowed to use
magic.


--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine

On Monday, December 26, 2016 at 11:44:10 AM UTC+13, Jeff Findley wrote:
In article ,
says...

General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7. This exceeds escape velocity of the moon already. In the vacuum of space or the near vacuum of Mars such a system easily achieves muzzle speeds 3x higher. These permit projectiles to travel between worlds at very low cost.

Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets. Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.

30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.

This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.

So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.

This all sounds quite unaffordable compared to utilizing the resources
we have here on earth.

Projecting an object from the surface of Mars at 14,100 mph in the right direction at the right time transports it to Earth. This requires 62 kWh of energy for a 25 pound round. With energy 'too cheap to meter' created on Mars with high temperature very low cost nuclear power plants, this costs 1/9th cent per kWh. 6.8 cents per round. 0.275 cents per pound - $5.50 per ton.


Also, once you shoot these things at earth, how do you propose to get
them safely to the surface?

I gave you the pointers to Teledyne's work on the EXACTO 50 cal round that is fired out of a cannon and guides a round imparting 220 mph to the round AFTER it leaves the barrel, using MEMS based solid propellant rockets, to guide the round to a precisely defined location using on board inertial guidance and optical sensors that detect a laser designator. General Atomics uses similar technology to guide its rounds in flight to close precisely on moving targets. Clearly ultra-low-cost MEMS based rockets are used in disposable delivery cannisters to deliver 25 pounds of cargo to precisely defined locations on Earth.

Having been launched from the Martian surface into a trans-Earth trajectory at 14,100 mph the round will fall toward Earth orbit. After falling 48,732,000 miles toward the Sun over 260 days, the round arrives at the top of Earth's atmosphere at 27,400 mph. By chosing the right trajectory, the arrival time can be varied by 24 hours. So, that the arrival longitude will be at the trajectory arrival point at the time of arrival. By chosing the arrival plane, the latitude of the arrival point is selected. This gives us complete freedom of choice of selection of the landing longitude and latitude. This brings the round to the VPA - vacuum perigee altitude. This is the point the round would reach over the Earth if it had no atmosphere. Momentum would carry the round back into interplanetary space if the Earth had no atmosphere. However, the Earth DOES have an atmosphere, and the VPA is well inside Earth's atmosphere. To achieve safe arrival of the round the round has a L/D of 1.6 through the speeds it operates in the Earth's atmosphere. It uses this lift to fly along an entry corridor that brings the round to rest over the longitude and latitude of its delivery point. The round is basically conical in shape. It will enter the atmosphere blunt end forward. Its center of pressure is offset from its center of gravity to a stable trim attitude producing lift. By rotating around the center of gravity the lift can be varied in direction to guide the round while passing through the Earth's atmosphere. After falling 48.7 million miles it arrives at the desired VPA + or - 15 miles. After entering the atmosphere the round has about 1,000 miles and 2.5 minutes of controllability. It falls until it reaches the first pull up point where it reaches maximum gee force and heat load. It then skips to about 400,000 feet altitude where it fall back down. This increases the range and controllability of the round allowing it to get closer to its landing point. It will then descend to its second pull up point where it slows to subsonic speeds and descends to its landing point. At 23,500 feet altitude it acquires its landing point via GPS and falls to it, igniting its MEMS based engines to brake its speed landing at zero altitude and zero speed precisely at the desired location.

Operationally, Martian producers will fire as many rounds as possible into the transfer orbit to Earth after conferring with the Mars/Earth exchanges for these products. Those products will be placed into a flight inventory during their 260 days transit, and qualified buyers may purchase these at wholesale prices. Those wholesalers will offer products for sale, delivered at the time of arrival, to retailers. Those retailers will then receive products at selling locations throughout Earth. Those locations and quantities will be scheduled for arrival to those retail locations after payment is received.

The delta vee required to achieve precise delivery is less than 335 mph. The delta vee required to bring the round to rest safely is 585 mph. A total of 920 mph. Each round has the capacity to alter its speed by 2,236 mph using MEMS based bipropellant cryogenic rockets with LOX/LH2 zero boil off cryogenic storage on board. The cost of this is very small. The 1.10 pound shell, contains 25 pound payload and 4.90 pounds LOX/LH2 propellant. The 90 pounds of thrust produced by the shell's rockets come from a 1.5 square inch of MEMS based 300 psi pressure fed rockets that produce 60 psi of thrust. At $0.10 per square inch, the propulsion system costs $0.15 per round. Total smart packaging cost less than $1.00 per round. It takes 15 kWh to make the 0.754 pounds of Hydrogen and 4.146 pound of Oxygen from 3.4 quarts of water. At 1/9th cent per kWh this adds 1-2/3 cents per round for propellant costs.


Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

On 12/26/2016 6:03 PM, William Mook wrote:

On Monday, December 26, 2016 at 11:44:10 AM UTC+13, Jeff Findley wrote:

In article ,
says...


General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7. This exceeds escape velocity of the moon already. In the vacuum of space or the near vacuum of Mars such a system easily achieves muzzle speeds 3x higher. These permit projectiles to travel between worlds at very low cost.

Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets. Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.

30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.

This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.

So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.


This all sounds quite unaffordable compared to utilizing the resources
we have here on earth.


Projecting an object from the surface of Mars at 14,100 mph in the right direction at the right time transports it to Earth. This requires 62 kWh of energy for a 25 pound round. With energy 'too cheap to meter' created on Mars with high temperature very low cost nuclear power plants, this costs 1/9th cent per kWh. 6.8 cents per round. 0.275 cents per pound - $5.50 per ton.



Also, once you shoot these things at earth, how do you propose to get
them safely to the surface?


I gave you the pointers to Teledyne's work on the EXACTO 50 cal round that is fired out of a cannon and guides a round imparting 220 mph to the round AFTER it leaves the barrel, using MEMS based solid propellant rockets, to guide the round to a precisely defined location using on board inertial guidance and optical sensors that detect a laser designator. General Atomics uses similar technology to guide its rounds in flight to close precisely on moving targets. Clearly ultra-low-cost MEMS based rockets are used in disposable delivery cannisters to deliver 25 pounds of cargo to precisely defined locations on Earth.

Having been launched from the Martian surface into a trans-Earth trajectory at 14,100 mph the round will fall toward Earth orbit. After falling 48,732,000 miles toward the Sun over 260 days, the round arrives at the top of Earth's atmosphere at 27,400 mph. By chosing the right trajectory, the arrival time can be varied by 24 hours. So, that the arrival longitude will be at the trajectory arrival point at the time of arrival. By chosing the arrival plane, the latitude of the arrival point is selected. This gives us complete freedom of choice of selection of the landing longitude and latitude. This brings the round to the VPA - vacuum perigee altitude. This is the point the round would reach over the Earth if it had no atmosphere. Momentum would carry the round back into interplanetary space if the Earth had no atmosphere. However, the Earth DOES have an atmosphere, and the VPA is well inside Earth's atmosphere. To achieve safe arrival of the round the round has a L/D of 1.6 through the speeds it operates in the Earth's atmosphere. It uses this lift to fly along an entry corridor that brings the round to rest over the longitude and latitude of its delivery point. The round is basically conical in shape. It will enter the atmosphere blunt end forward. Its center of pressure is offset from its center of gravity to a stable trim attitude producing lift. By rotating around the center of gravity the lift can be varied in direction to guide the round while passing through the Earth's atmosphere. After falling 48.7 million miles it arrives at the desired VPA + or - 15 miles. After entering the atmosphere the round has about 1,000 miles and 2.5 minutes of controllability. It falls until it reaches the first pull up point where it reaches maximum gee force and heat load. It then skips to about 400,000 feet altitude where it fall back down. This increases the range and controllability of the round allowing it to get closer to its landing point. It will then descend to its second pull up point where it slows to subsonic speeds and descends to its landing point. At 23,500 feet altitude it acquires its landing point via GPS and falls to it, igniting its MEMS based engines to brake its speed landing at zero altitude and zero speed precisely at the desired location.

Operationally, Martian producers will fire as many rounds as possible into the transfer orbit to Earth after conferring with the Mars/Earth exchanges for these products. Those products will be placed into a flight inventory during their 260 days transit, and qualified buyers may purchase these at wholesale prices. Those wholesalers will offer products for sale, delivered at the time of arrival, to retailers. Those retailers will then receive products at selling locations throughout Earth. Those locations and quantities will be scheduled for arrival to those retail locations after payment is received.

The delta vee required to achieve precise delivery is less than 335 mph. The delta vee required to bring the round to rest safely is 585 mph. A total of 920 mph. Each round has the capacity to alter its speed by 2,236 mph using MEMS based bipropellant cryogenic rockets with LOX/LH2 zero boil off cryogenic storage on board. The cost of this is very small. The 1.10 pound shell, contains 25 pound payload and 4.90 pounds LOX/LH2 propellant. The 90 pounds of thrust produced by the shell's rockets come from a 1.5 square inch of MEMS based 300 psi pressure fed rockets that produce 60 psi of thrust. At $0.10 per square inch, the propulsion system costs $0.15 per round. Total smart packaging cost less than $1.00 per round. It takes 15 kWh to make the 0.754 pounds of Hydrogen and 4.146 pound of Oxygen from 3.4 quarts of water. At 1/9th cent per kWh this adds 1-2/3 cents per round for propellant costs.






Have you factored in the cost of spending 20% of the
annual disposable income of the entire United States
federal budget times 20 years to build the Mars Colonies?







Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

On Monday, December 26, 2016 at 1:47:53 PM UTC+13, Fred J. McCall wrote:
William Mook wrote:


General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7.


No, it doesn't. Try 10 rounds per minute and even that isn't working
yet at those kinds of rates for long because of heat issues and rail
erosion and ablation.

Already publicly GA is reporting 60 rounds per minute, FROM A SINGLE RAIL. By stacking rounds in the barrel, over 14,000 rounds per minute is achieved. That's 233 rounds per second - well above the 30 rounds per second I've quoted.

http://www.defensetech.org/2010/05/0...c-rail-cannon/

Using multiple rounds per rail, and multiple rails with high current switching between them, its fairly easy to see that millions of rounds per minute can be achieved, as has been achieved with more traditional methods of propelling rounds.

https://www.youtube.com/watch?v=wKlnMwuCZso
https://www.youtube.com/watch?v=AEu9LLQpOF8

So, why did I quote 1,800 rounds per minute (30 rounds per second)? Because you have to reload and resurface the rails, and recharge the capacitor bank.






Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets.


Yes, it's a little tiny lightweight projectile.

Haha. You have no idea how things scale do you? Fact is, the 25 pound Blitzer fired projectile already has a guidance system on it. A 50 cal round weighs 1.73 ounces actually shows just how small lightweight and low cost these guidance systems can be. The EXACTO round masses 1.73 ounces - the Blitzer round weighs 25 pounds and a B61-12 weighs 700 pounds! All have guidance systems on them and use a combination of aerodynamic and rocket forces to guide them to their targets.


Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.


Handwavium.

Nonsense. Saying we're going to use abundant water resources and energy resources found in place on either the moon or Mars to produce cryogenic zero boil off lox/lh2 propellants to cheaply guide rounds to customers on Earth is the exact opposite of hand waving. Its very precise and gives a clear indication exactly how things work.

MEMS rockets deliver only small amounts of thrust (hence
'MEMS').

Liquid bipropellant rockets have been made that produce 50 psi using 300 psi pressure fed propellants. A square inch of these cost less than $1 in quanitity on Earth, and vastly less on Mars given the lower energy resource and labour costs.

You can't just paste a zillion of them on something and
multiply.

I just bought a 4K, Ultra HD, TV. This has a resolution of 3,840 x 2,160 pixels four colour pixels. That's four times the 1,920 x 1,080 pixels found in your full HD TV. That's 33.17 million plasma points that are switched at 120 times per second through a dynamic range of 12,000 to 1 across a 65" diagonal screen. This is a screen that's 31.87 inches tall and 56.65 inches wide and has an area of 1805.3 square inches. Retail this is $5 per square inch. On Mars this would cost $0.05 per square inch to produce given the lower labour, energy, taxes, regulatory and resource costs. At 50 psi exit plane pressure a MEMS array the size of this screen using very much the same control methodology, would produce 90,267 pounds of force under highly controlled conditions.

You have now also added heavy insulated tanks to your
'cheap carrier'.

Advanced tanks,

http://www.compositesworld.com/artic...s-for-cryogens
http://www.hydrogencarsnow.com/index...iquid-h2-fuel/

Advanced cryocoolers,

http://link.springer.com/chapter/10....19-2_25#page-1
http://iopscience.iop.org/article/10...16/10/002/meta
http://www.colorado.edu/MCEN/mems/research_simon1.htm

Built at very low cost, in quantities of billions rather than dozens, are easily achieved.

You can't go solid fuel because you need to be able
to turn them on and off.

When you have millions of engines across your thrust surface and several surfaces stacked in layers, you can produced controlled thrust across that surface.

The only liquid fuel MEMS rockets I've seen
anyone talking about use hydrogen peroxide, not deeply cryogenic fuels

Why doesn't that surprise me.

(although feel free to cite such an engine) and they only manage tiny
amounts of thrust. Their thrust/weight ratios are high, but that
rapidly goes to **** once you start adding plumbing, tanks, multiple
engines, etc.

The Shuttle External Tank achieves a tank mass fraction of 3.71% of the propellant it carries at 22 psi for the LOX and 29 psi for the LH2. With advanced construction techniques this same level of performance (4%) is achieved at 300 psi.

https://www.nasa.gov/pdf/382034main_...k_Masses. pdf

Thrust to weight ratios of 1000 to 1 are achieved with MEMS based engines as you point out. So, a 4.9 lb propellant tank will weigh less than 0.2 lbs and a 90 lb MEMS thrust array will weigh less than 0.1 lbs.


30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.


Now divide your numbers by 180 for a realistic firing rate,

General Atomics already reports 14,000 rounds per minute from their Blitzer.. This is 233 rounds per second. I'm proposing 30 rounds per second - largely due to reloading concerns.

deduct the
weight of all the extra **** you have to put on the round for
midcourse corrections and surviving reentry, and adopt a realistic
maintenance cycle for your equipment.

The round is 33.1 pounds to carry a 25 pound useful cargo. If you wish to limit the entire system to 25 pounds then the cargo is reduced to 19 ponds.



This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.


Yeah, because I WANT projectiles doing interplanetary speeds slamming
into my house.

They won't, any more than oil tankers will slam into your house, or any more than your house will be covered with crude oil.



So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.


No reason unless you live in the real world and aren't allowed to use
magic.


The world you live in is certainly different than mine. That makes your world less real in many respects because the real world has inertially guided 50 calibre rounds using MEMS rockets, the real world has magnetically launched rounds also inertially guided capable of achieving planetary escape velocities firing at rates well in excess of 1800 rounds per minute, the real world has planets with vastly more resources than exist on Earth free of many of the constraints that we face here.


--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine

In article ,
says...

Have you factored in the cost of spending 20% of the
annual disposable income of the entire United States
federal budget times 20 years to build the Mars Colonies?

Clearly he has not. All this is "free":

1. The many nuclear reactors on Mars.
2. The "rail guns" to launch the payloads.
3. The manufacturing plant that makes the "rounds" (including propulsion
and zero boil off LOX/LH2 storage, computer, sensors, communications,
and etc)
4. The mining facilities and processing facilities for the payload.
5. The tracking and communications arrays to keep the rounds on target
during their long journey back to earth.
6. And on and on and on...

The glaring flaw in all of this is that even if the above were all
possible, why the hell would a Mars colony devote all of the above
effort to support the earth? Why not use the above facilities to
produce goods for Mars?

Somehow, on top of the science fiction of firing projectiles at earth
that provide useful payload, Mook has also completely suspended basic
economics on Mars. Because people born and bred on Mars would never
turn against their colonial overlords that are bleeding Mars dry of
natural resources. right? It's not like that's ever happened before on
earth, has it? ;-)

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

On Tuesday, December 27, 2016 at 1:29:54 PM UTC+13, Jonathan wrote:
On 12/26/2016 6:03 PM, William Mook wrote:
On Monday, December 26, 2016 at 11:44:10 AM UTC+13, Jeff Findley wrote:
In article ,
says...

General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7. This exceeds escape velocity of the moon already. In the vacuum of space or the near vacuum of Mars such a system easily achieves muzzle speeds 3x higher. These permit projectiles to travel between worlds at very low cost.

Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets. Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.

30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.

This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.

So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.

This all sounds quite unaffordable compared to utilizing the resources
we have here on earth.

Projecting an object from the surface of Mars at 14,100 mph in the right direction at the right time transports it to Earth. This requires 62 kWh of energy for a 25 pound round. With energy 'too cheap to meter' created on Mars with high temperature very low cost nuclear power plants, this costs 1/9th cent per kWh. 6.8 cents per round. 0.275 cents per pound - $5.50 per ton.


Also, once you shoot these things at earth, how do you propose to get
them safely to the surface?

I gave you the pointers to Teledyne's work on the EXACTO 50 cal round that is fired out of a cannon and guides a round imparting 220 mph to the round AFTER it leaves the barrel, using MEMS based solid propellant rockets, to guide the round to a precisely defined location using on board inertial guidance and optical sensors that detect a laser designator. General Atomics uses similar technology to guide its rounds in flight to close precisely on moving targets. Clearly ultra-low-cost MEMS based rockets are used in disposable delivery cannisters to deliver 25 pounds of cargo to precisely defined locations on Earth.

Having been launched from the Martian surface into a trans-Earth trajectory at 14,100 mph the round will fall toward Earth orbit. After falling 48,732,000 miles toward the Sun over 260 days, the round arrives at the top of Earth's atmosphere at 27,400 mph. By chosing the right trajectory, the arrival time can be varied by 24 hours. So, that the arrival longitude will be at the trajectory arrival point at the time of arrival. By chosing the arrival plane, the latitude of the arrival point is selected. This gives us complete freedom of choice of selection of the landing longitude and latitude. This brings the round to the VPA - vacuum perigee altitude. This is the point the round would reach over the Earth if it had no atmosphere. Momentum would carry the round back into interplanetary space if the Earth had no atmosphere. However, the Earth DOES have an atmosphere, and the VPA is well inside Earth's atmosphere. To achieve safe arrival of the round the round has a L/D of 1.6 through the speeds it operates in the Earth's atmosphere. It uses this lift to fly along an entry corridor that brings the round to rest over the longitude and latitude of its delivery point. The round is basically conical in shape. It will enter the atmosphere blunt end forward. Its center of pressure is offset from its center of gravity to a stable trim attitude producing lift. By rotating around the center of gravity the lift can be varied in direction to guide the round while passing through the Earth's atmosphere. After falling 48.7 million miles it arrives at the desired VPA + or - 15 miles. After entering the atmosphere the round has about 1,000 miles and 2.5 minutes of controllability. It falls until it reaches the first pull up point where it reaches maximum gee force and heat load. It then skips to about 400,000 feet altitude where it fall back down. This increases the range and controllability of the round allowing it to get closer to its landing point. It will then descend to its second pull up point where it slows to subsonic speeds and descends to its landing point. At 23,500 feet altitude it acquires its landing point via GPS and falls to it, igniting its MEMS based engines to brake its speed landing at zero altitude and zero speed precisely at the desired location.

Operationally, Martian producers will fire as many rounds as possible into the transfer orbit to Earth after conferring with the Mars/Earth exchanges for these products. Those products will be placed into a flight inventory during their 260 days transit, and qualified buyers may purchase these at wholesale prices. Those wholesalers will offer products for sale, delivered at the time of arrival, to retailers. Those retailers will then receive products at selling locations throughout Earth. Those locations and quantities will be scheduled for arrival to those retail locations after payment is received.

The delta vee required to achieve precise delivery is less than 335 mph.. The delta vee required to bring the round to rest safely is 585 mph. A total of 920 mph. Each round has the capacity to alter its speed by 2,236 mph using MEMS based bipropellant cryogenic rockets with LOX/LH2 zero boil off cryogenic storage on board. The cost of this is very small. The 1.10 pound shell, contains 25 pound payload and 4.90 pounds LOX/LH2 propellant. The 90 pounds of thrust produced by the shell's rockets come from a 1.5 square inch of MEMS based 300 psi pressure fed rockets that produce 60 psi of thrust. At $0.10 per square inch, the propulsion system costs $0.15 per round. Total smart packaging cost less than $1.00 per round. It takes 15 kWh to make the 0.754 pounds of Hydrogen and 4.146 pound of Oxygen from 3.4 quarts of water. At 1/9th cent per kWh this adds 1-2/3 cents per round for propellant costs.





Have you factored in the cost of spending 20% of the
annual disposable income of the entire United States
federal budget times 20 years to build the Mars Colonies?

No, because this isn't required. NASDAQ for example trades $60 million worth of stock each day. Over the course of a year over $21.9 trillion is traded by this exchange alone! NASDAQ completes an IPO for a new company once every six days and raises an average of $260 million per start up company. A total of $16 billion per year. The value of 3,100 companies last year rose by $2.04 trillion an average of $658 million per company.

NASA spent $19 billion last year. Russia's Federal Space Agency, and Europe's ESA spent $5.5 billion each last year. JAXA, Japan's space agency spend $2.2 billion last year. CNSA China's space agency $1.2 billion. India's space agency $0.9 billion.

http://www.eia.gov/todayinenergy/detail.php?id=16011

42 independent oil and gas produced 39% of the world's energy supplies and have a combined worth of $2.4 trillion. An average of $57 billion each. They spend $650 billion per year EXPLORING for oil and gas resources. Only 18% of their fields are ever productive. 82% are not. So, they're used to high risk!

So, the markets don't need to rely on the working stiffs or the governments for their capital. All they need do is deal with someone qualified who has a real opportunity to make a profit in the areas they do business in and are knowledgeable enough to structure a deal that makes sense properly apportioning risks.

As of 2015, there were 172,850 people with USD$30 million or more in liquid assets. A number 61% higher than 10 years earlier, and 1,844 of these individuals with over $1 billion in liquid assets, an 82% increase over the number of billionaires in the previous decade. Together, these individuals hold $20.8 trillion. Although they constitute only 0.003% of the world’s population, they hold 13% of the world's total wealth.

This is where investment decisions are made regarding humanity's future. They are nearly all highly educated. The current generation of high net worth individuals have fully bought into the need for population reduction and reducing humanity's impact on the environment. This mind set that industrial development is a bad thing for them, their children, and the community in general, has done more to shape the allocation of capital today, and lead military and government planners along the paths they are currently following.

The inability of aerospace companies and the aerospace community in general to not usefully engage these people in a meaningful way has done more to alienate this population against real space development than anything else. Just mentioning the possibility of sending iron to Earth more cheaply and in greater abundance than it can be done on Earth provokes outrageous respnoses we see here. Like I said, no one with the capital needed to make real changes in the way we approach space will make those investments in the current political, scientific, regulatory and economic environment.

Its not that we don't have the capital, we have a huge disconnect between the science, the capital and the government management of both.

There are outliers. People like Elon Musk took an interest in my analysis of TRW's acquisition by Northrup back in the day and that resulted in the present SpaceX. Bezos, and others are following other paths.

Reusable two or three stages to orbit is the first development that will transform the BUSINESS of space travel. I speak more to that end here;

https://www.linkedin.com/pulse/space...mp-reader-card

A three element launcher using LOX/LNG at $0.07 per pound for propellant, and carrying 3,568,695 pounds of propellant in three flight elements, each of which mass 49,565 pounds empty, and carry a 119,900 pound payload to orbit.

Six element launcher -with four added propelled tanks, each capable of flying back to the launch centre - with the two second stage tanks circling the Earth and flying back to the launch centre, and the third stage tank deorbiting and making its way back the launch centre - this puts 335,000 pounds into LEO.

A dozen 9,000 pound communications satellites may be put up per launch, costing $250,000 in fuel, and another $150,000 in other costs - a grand total of $400,000 per the smaller vehicle. 37 comsats may be orbited by the largrer vehicle for $583,000 in fuel costs and $167,000 in other costs - $750,000 per launch.

200 flights per year, and a 20 year life span, 4,000 flights over the vehicle's life time. With $16 million construction cost per tank the capital cost is $4,000 per tank per flight. A three tank vehicle has a cost of $12,000 per flight. A seven tank system has $28,000 per flight - included in the other costs.

An inflatable thin film concentrator that powers a high efficiency solar pumped laser on orbit generates 10,000 watts per pound of payload at 1 AU from Sol. The three tank system orbits a 1.19 billion watt power plant. The seven tank system orbits a 3.35 billion watt power plant.

Delivering pollution free energy to Earth at $0.11 per kWh 24/7 anywhere its demanded generates $1.15 billion per year in revenue for the smaller satellite and $3.23 billion per year per satellite for the larger launcher.

Total energy demand on Earth is 12.2 trillion watts a total of 107.8 trillion kWh. This is worth $11.8 trillion at $0.11 per kWh. A total of 3,672 satellites are required to displace all the world's legacy fuel supplies. This occurs in less than four years with only 10 launchers of the type described above.

Communications satellites can support the present demand of 1.1 zetabytes per year (279 terabytes per second) and capture the $1.68 trillion spent each year on telecommunications. New services can be delivered anywhere, including telepresence and telerobotics. This can be done with a small satellite network orbited by only a few of the launchers previously described.

Over $12 trillion may be earned from the sale of energy and communications services by controlling the delivery of 3,672 power satellites and fewer than 700 communications satellites launched by a fleet of ten launchers each delivering 200 launches per year.

With this sort of revenue stream, the owners can then buy up the remaining aerospace companies and extract from them their unique value, turn it toward the production of deep space capabilities.

The DOE will dismantle over 2,300 nuclear weapons by 2020AD and dismantle another 2,300 more by 2025 AD. They are currently seeking commercial buyers qualified to take this inventory. A qualifed aerospace company with the revenue discussed here, could easily put together a business plan that launch subcritical components to Mars, and assemble them robotically into high temperature nuclear reactors that would then;

(1) process the abundant iron ore giving Mars its characteristic colour,
(2) launch the resulting steel to Earth with magnetic mass drivers at very low cost,
(3) develop compact, safe and reliable nuclear energy units for;
(a) space power - including space colonies,
(b) space propulsion

With multi-gigawatt laser beams capable of producing 75 tons of force to lift 50 ton vehicles off the pad, with exhaust velocities of 20,570 mph. Such vehicles easily produce SSTO vehicle with inert propellants like water, and lift 31,780 pounds cheaply into orbit.

The same laser beams can power ion engines at far higher efficiency to send vehicles of 335,000 pounds to Mars, Ceres or Vesta, along rapid orbits using very little propellant.

Similar systems operating above and around Mars, as well as around Vesta and Ceres, provide power, illumination, and propulsion for vehicles arriving and departing the planet. Magnetic mass drivers provide very low cost payload deliver between worlds.









Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

William Mook wrote:

On Monday, December 26, 2016 at 11:44:10 AM UTC+13, Jeff Findley wrote:
In article ,
says...

General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7. This exceeds escape velocity of the moon already. In the vacuum of space or the near vacuum of Mars such a system easily achieves muzzle speeds 3x higher. These permit projectiles to travel between worlds at very low cost.

Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets. Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.

30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.

This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.

So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.

This all sounds quite unaffordable compared to utilizing the resources
we have here on earth.

Projecting an object from the surface of Mars at 14,100 mph in the right direction at the right time transports it to Earth. This requires 62 kWh of energy for a 25 pound round. With energy 'too cheap to meter' created on Mars with high temperature very low cost nuclear power plants, this costs 1/9th cent per kWh. 6.8 cents per round. 0.275 cents per pound - $5.50 per ton.


I'll just note that even while still assuming magic technology
(electricity on Mars being an order of magnitude cheaper than
electricity on Earth due to numbers you apparently grabbed out of your
ass) your claimed cost per ton has grown by two orders of magnitude
and your 30 rounds per second every second of every day has collapsed
to "the right direction at the right time".


Also, once you shoot these things at earth, how do you propose to get
them safely to the surface?

I gave you the pointers to Teledyne's work on the EXACTO 50 cal round that is fired out of a cannon and guides a round imparting 220 mph to the round AFTER it leaves the barrel, using MEMS based solid propellant rockets, to guide the round to a precisely defined location using on board inertial guidance and optical sensors that detect a laser designator. General Atomics uses similar technology to guide its rounds in flight to close precisely on moving targets. Clearly ultra-low-cost MEMS based rockets are used in disposable delivery cannisters to deliver 25 pounds of cargo to precisely defined locations on Earth.


50 caliber rounds aren't fired out of cannons. General Atomics uses
aerodynamics (not Mookie's Magical MEMS Rockets (tm)) to guide its
rounds.

snip MookSpew


--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine

William Mook wrote:

On Monday, December 26, 2016 at 1:47:53 PM UTC+13, Fred J. McCall wrote:
William Mook wrote:


General Atomics markets a rail gun that shoots 30 rounds per second 25 pounds each at Mach 7.


No, it doesn't. Try 10 rounds per minute and even that isn't working
yet at those kinds of rates for long because of heat issues and rail
erosion and ablation.

Already publicly GA is reporting 60 rounds per minute, FROM A SINGLE RAIL. By stacking rounds in the barrel, over 14,000 rounds per minute is achieved. That's 233 rounds per second - well above the 30 rounds per second I've quoted.

http://www.defensetech.org/2010/05/0...c-rail-cannon/


Note: "working on" vice "reporting".


Using multiple rounds per rail, and multiple rails with high current switching between them, its fairly easy to see that millions of rounds per minute can be achieved, as has been achieved with more traditional methods of propelling rounds.

https://www.youtube.com/watch?v=wKlnMwuCZso
https://www.youtube.com/watch?v=AEu9LLQpOF8


MetalStorm ain't the same thing as a railgun, you nitwit. Trying to
fire 'multiple rounds per rail' is a particularly spectacular way to
blow up your launcher.


So, why did I quote 1,800 rounds per minute (30 rounds per second)?

Because that was the first number you found when you reached into your
ass.


Because you have to reload and resurface the rails, and recharge the capacitor bank.


Neither of those occurred to you until I mentioned them. You were
shooting every second of every day of every year. Magic.




Teledyne and Cubic already market a self guided 50 cal round. These impart up to 150 m/s delta ver to bullets ising MEMs solid rockets.


Yes, it's a little tiny lightweight projectile.

Haha. You have no idea how things scale do you? Fact is, the 25 pound Blitzer fired projectile already has a guidance system on it. A 50 cal round weighs 1.73 ounces actually shows just how small lightweight and low cost these guidance systems can be. The EXACTO round masses 1.73 ounces - the Blitzer round weighs 25 pounds and a B61-12 weighs 700 pounds! All have guidance systems on them and use a combination of aerodynamic and rocket forces to guide them to their targets.


Haha. It's you who has no idea how things scale. The fact that you
can multiply doesn't mean you can just scale up. This is why I label
so many of your 'calculations' as "MookieMath".


Adapted to use the water and energy resources of the moon and Mars using cryogenic ZBO lox/lh2 MEMs rockets these easily provide sufficient guidance to deliver products anywhere required cheaply.


Handwavium.

Nonsense. Saying we're going to use abundant water resources and energy resources found in place on either the moon or Mars to produce cryogenic zero boil off lox/lh2 propellants to cheaply guide rounds to customers on Earth is the exact opposite of hand waving. Its very precise and gives a clear indication exactly how things work.


Except things don't work that way. Hence "handwavium".

MEMS rockets deliver only small amounts of thrust (hence
'MEMS').

Liquid bipropellant rockets have been made that produce 50 psi using 300 psi pressure fed propellants. A square inch of these cost less than $1 in quanitity on Earth, and vastly less on Mars given the lower energy resource and labour costs.


So why don't you past a couple square feet of the things to your ass
and fly to the Moon?

You can't just paste a zillion of them on something and
multiply.

I just bought a 4K, Ultra HD, TV. This has a resolution of 3,840 x 2,160 pixels four colour pixels. That's four times the 1,920 x 1,080 pixels found in your full HD TV. That's 33.17 million plasma points that are switched at 120 times per second through a dynamic range of 12,000 to 1 across a 65" diagonal screen. This is a screen that's 31.87 inches tall and 56.65 inches wide and has an area of 1805.3 square inches. Retail this is $5 per square inch. On Mars this would cost $0.05 per square inch to produce given the lower labour, energy, taxes, regulatory and resource costs. At 50 psi exit plane pressure a MEMS array the size of this screen using very much the same control methodology, would produce 90,267 pounds of force under highly controlled conditions.


I'm happy you have a nice TV, but the rest of that is bull****.

You have now also added heavy insulated tanks to your
'cheap carrier'.

Advanced tanks,

http://www.compositesworld.com/artic...s-for-cryogens
http://www.hydrogencarsnow.com/index...iquid-h2-fuel/

Advanced cryocoolers,

http://link.springer.com/chapter/10....19-2_25#page-1
http://iopscience.iop.org/article/10...16/10/002/meta
http://www.colorado.edu/MCEN/mems/research_simon1.htm

Built at very low cost, in quantities of billions rather than dozens, are easily achieved.


'Easily achieved' means "because Mook says so". Handwavium

You can't go solid fuel because you need to be able
to turn them on and off.

When you have millions of engines across your thrust surface and several surfaces stacked in layers, you can produced controlled thrust across that surface.


And if you have magic pixie dust you can do whatever you want.

The only liquid fuel MEMS rockets I've seen
anyone talking about use hydrogen peroxide, not deeply cryogenic fuels

Why doesn't that surprise me.


Because there aren't any?

(although feel free to cite such an engine) and they only manage tiny
amounts of thrust. Their thrust/weight ratios are high, but that
rapidly goes to **** once you start adding plumbing, tanks, multiple
engines, etc.

The Shuttle External Tank achieves a tank mass fraction of 3.71% of the propellant it carries at 22 psi for the LOX and 29 psi for the LH2. With advanced construction techniques this same level of performance (4%) is achieved at 300 psi.

https://www.nasa.gov/pdf/382034main_...k_Masses. pdf

Thrust to weight ratios of 1000 to 1 are achieved with MEMS based engines as you point out. So, a 4.9 lb propellant tank will weigh less than 0.2 lbs and a 90 lb MEMS thrust array will weigh less than 0.1 lbs.


I note you don't cite any such cryogenic MEMS rockets. I also note
your arithmetic above is, well, full of logical flaws. The thrust to
weight ratio of AN ENGINE has nothing to do with tank weights. I find
it interesting how you magically make 4.9 lbs weight 0.2 lbs and so
on. Magic.


30 rounds per second x 25 pounds per round x 3600 seconds per hour x 8766 hours per year =
23.66 billion pounds per year per launcher to nearly a billion location each year.


Now divide your numbers by 180 for a realistic firing rate,

General Atomics already reports 14,000 rounds per minute from their Blitzer. This is 233 rounds per second. I'm proposing 30 rounds per second - largely due to reloading concerns.


Horse****. Cite or admit you're lying.

deduct the
weight of all the extra **** you have to put on the round for
midcourse corrections and surviving reentry, and adopt a realistic
maintenance cycle for your equipment.

The round is 33.1 pounds to carry a 25 pound useful cargo. If you wish to limit the entire system to 25 pounds then the cargo is reduced to 19 ponds.


Mookery of the facts. Your number are whacked, no matter how you
scale them.



This is on par with a fleet of bulk ocean carriers or railroads with the added capacity to deliver r directly to consumers.


Yeah, because I WANT projectiles doing interplanetary speeds slamming
into my house.

They won't, any more than oil tankers will slam into your house, or any more than your house will be covered with crude oil.


So *NOT* "delivering directly to consumers", then.



So there is no reason to believe off world colonies cannot trade with Earth as easily as power or information can be delivered to Earth by off world assets.


No reason unless you live in the real world and aren't allowed to use
magic.


The world you live in is certainly different than mine. That makes your world less real in many respects because the real world has inertially guided 50 calibre rounds using MEMS rockets, the real world has magnetically launched rounds also inertially guided capable of achieving planetary escape velocities firing at rates well in excess of 1800 rounds per minute, the real world has planets with vastly more resources than exist on Earth free of many of the constraints that we face here.


Do you know what the phrase "inertially guided" means? It appears
not, since EXACTO is NOT 'inertially guided', which is sort of the
point of the thing. As for the rest of your Mookery of reality,
'magical'.

How's that Lunar XPrize going for you, Mookie? 'Magical'...


--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine