The Moon or Mars?

There have been a lot of articles in the news about either returning to the Moon or going to Mars of late.  I think they are great.  Either destination is fine as long as we build the infrastructure that will make spaceflight affordable to everyone in the process.

My reasons for this are simple; whichever program we choose, I don’t want it to be canceled after a handful of missions due to excessive cost like the Apollo program was.  If we make spaceflight really affordable the program will continue and people will find a way to make money in space.  Once that happens we will be on our way towards building a spacefaring civilization and there will be no turning back.

Returning to the Moon or going to Mars without building the infrastructure to make spaceflight affordable will only result in another canceled program and another 40 to 50-year wait before we try again.  The reason for this is simple.  Currently, it costs over $12,000 per pound to go to the International Space Station.  You can check this yourself by going to the SpaceX website and looking up the cost of flying the Falcon 9 launch vehicle.  It is $62 million per flight.  If you look up the amount of useful payload that it can deliver to the International Space Station, the answer is 5,000 pounds.  $62 million divided by 5,000 equals $12,400 per pound.

Another example is the Space Launch System, NASA’s new heavy-lift rocket that is currently in the process of being developed.  The Block 1 version of this rocket is supposed to be able to lift 150,000 pounds into low Earth orbit.  The cost per flight is estimated to be $1.86 billion.  That also comes out to $12,400 per pound.

The Saturn V rocket that was used to go to the Moon in the 1960s would launch 3 astronauts and 140,000 kilograms into low Earth orbit for each Moon mission.  That is a little over 300,000 pounds or 100,000 pounds per astronaut.  100,000 times 12,400 equals $1.24 billion per astronaut in today’s dollars to go to the Moon.  You can be sure that sending an astronaut to Mars will cost more than that.  Even if the reusable first stage rocket technology that is being developed by SpaceX and Blue Origin is able to reduce the cost of getting into Earth orbit by half, the cost per astronaut for going to either the Moon or Mars will still be in excess of $600 million per person.  That is a lot of money.  So much money that no one has been able to come up with a commercial activity in space that can make enough money to justify the expense of manned spaceflight.

As much as I want to see us build a spacefaring civilization, it just isn’t going to happen with launch costs this high.  Anyone who tells you otherwise is either living in a fantasy world or expects to make money on it via government contracts.

So what can we do?

There are 3 things we need to do to make spaceflight affordable if we want to build a spacefaring civilization.

First, build a combination launch system that includes either an air-launched reusable first stage rocket for flying to the lower end of a non-rotating Skyhook or build a 600 MPH ground accelerator for launching a reusable first stage rocket to a non-rotating Skyhook.

Second, build a reusable spacecraft for launching from the upper end of the Skyhook for going either to the Moon or to Mars, as well as single stage reusable lander for the Moon or Mars.

Third, build outpost space stations with local sources of propellant for refueling those spacecraft and landers.

It doesn’t all have to be built at once.  It can be built a piece at a time with jointly funded government/industry programs.  SpaceX and Blue Origin are working on reusable rockets.  Vulcan Inc. is developing the Stratolaunch carrier aircraft for air-launching launch vehicles.  Bigelow Aerospace is developing inflatable space stations.  NASA is building the Orion spacecraft for cis-lunar spaceflight and possibly for going to Mars.  And finally, the US Air Force is developing a Maglev test track that could be used to accelerate a launch vehicle up to 600 MPH.

What else do we need?

Vulcan Inc. needs to develop a horizontal landing reusable first stage launch vehicle for its Stratolaunch carrier aircraft, and either NASA or Bigelow Aerospace needs to add a 200-kilometer long tether to the International Space Station or to a Bigelow space station along the lines of the one shown in this video.

Air-launching and the 200-kilometer long Skyhook will reduce the cost to orbit to 1/3 of what it is today, from $12,000 per pound to $4,000 per pound.  Making the air-launched first stage reusable should reduce the cost to $2,000 per pound.  Increase the length of the Skyhook to 380 kilometers and the cost will drop to $1,500 per pound.  Continue making the Skyhook longer and the price drops even more.  Once the Skyhook is long enough that the upper end is moving at close to escape velocity it becomes possible to place an Orion spacecraft on a free-return orbit to the Moon without the need for an expendable upper stage.  Add a single stage reusable lunar lander and an outpost space station in lunar orbit and now we have an affordable transportation system for going to the Moon.

Before the Space Shuttle was retired we had the beginnings of a space tourism industry with people like Dennis Tito flying to the International Space Station.  The cost for such a flight was $20 million.  An air-launched reusable first stage launch vehicle flying to the lower end of a 380-kilometer long Skyhook equipped space station would cost 1/8th of that, or approximately $2.5 million.  Obviously, there will be more people wanting to go into space at that price than for what Dennis Tito paid.  Increased demand for flights will justify additional investment in the Skyhook to make it longer as a longer Skyhook will decrease the price even more.  Every time the price goes down the demand for flights will increase.  The increased demand will lead to further increases in the length of the Skyhook.  Eventually, it will reduce the cost of a ride to orbit to $20,000 per person.  That is what I call affordable to everyone spaceflight.

As the number of people in orbit increases, it will eventually become economically worthwhile to develop an off-planet source of consumables such as water and oxygen.  No matter how affordable the combination launch system becomes, it will always be more affordable to get basics such as water, oxygen, and shielding materials from either the Moon or an asteroid due to the lower energy requirements for going to those places.  Once we have access to those materials, building farm modules for growing food in space will also become worthwhile.

Having a NASA program for returning to the Moon or going to Mars will speed up the development of the combination launch system due to the increased demand for flights.  This will speed up the pace of development in commercial manned spaceflight as well as reduce the cost of the NASA program.  It is a win-win combination that will propel us into the solar system and kickstart the building of a spacefaring civilization.

We are that close to making it all happen.

Ad Astra

 

Index of Articles

  1. Opening the High Frontier
  2. Skyhook, a Journey to Orbit and Beyond
  3. In the Beginning . . .
  4. Why do Rockets Cost so Much?
  5. Combination Launch Systems
  6. It’s All About Speed!
  7. Visions of the Future
  8. The Call of an Unlimited Future
  9. Combination Launch Systems, part 2
  10. Outward Bound: Beyond Low Earth Orbit
  11. and someday . . . Starships!
  12. Mars: how to get there
  13. Outpost Space Stations
  14. Dreams of Space
  15. The Moon or Mars?
  16. Skyhooks and Space Elevators

Dreams of Space

What are your dreams of space?

People have dreamed about building cities on the Moon and Mars for years.

Some people even dream of making Mars into an earthlike planet – a true second home for mankind.

Others want to go asteroid mining so as to bring home the wealth of the solar system.

There are others who want to build cities in the stars, O’Neill style space colonies scattered throughout the solar system, to develop a truly space based civilization.

They are all worthy and wonderful dreams.  Yet none of them will happen until a way is found to make space travel affordable to everyone.  Affordable to the individual spaceflight is the foundation of all these dreams if any of them are ever to be made real.

Affordable to everyone spaceflight is not just about the big dreams, it is also about the personal dreams of every person who has the courage to dream.  For some, that personal dream might be to spend a week or two in an orbiting hotel watching the Earth pass by underneath.

For others, it might be to get a job in one of the orbiting factories or research stations so as to become part of the new frontier.

Then there are those who dream of starting their own business in space such as a repair and refueling service for satellites that orbit the Earth or to build a farm module where they can make a living growing food for the people who live and work in space.

Other still might dream of getting a job in space so they can use their spare time to build a small spaceship that will allow them to homestead an asteroid.

The possibilities are endless.  The only limitation is your imagination and how hard you are willing to work.

Whatever your dreams of space are, affordable to everyone spaceflight is what will make them possible.  Without it, all these dreams, both large and small, will remain forever unattainable.

Isn’t it time we built a combination launch system that will make all this possible?

 

Index of Articles

  1. Opening the High Frontier
  2. Skyhook, a Journey to Orbit and Beyond
  3. In the Beginning . . .
  4. Why do Rockets Cost so Much?
  5. Combination Launch Systems
  6. It’s All About Speed!
  7. Visions of the Future
  8. The Call of an Unlimited Future
  9. Combination Launch Systems, part 2
  10. Outward Bound: Beyond Low Earth Orbit
  11. and someday . . . Starships!
  12. Mars: how to get there
  13. Outpost Space Stations
  14. Dreams of Space
  15. The Moon or Mars?
  16. Skyhooks and Space Elevators

The Call of an Unlimited Future

In 2014, Erik Wernquist released a short film about his vision of our future called “Wanderers”.  It shows an incredible and wondrous future that sets no limits on what we can do and on what we might become.  Every bit of it is within our reach.  The only thing that is missing is the vision on how to make that first step, the step from the surface of the Earth to orbit and to escape velocity, affordable to everyone.

Think about that as you watch it.

All it will take to make this happen in the real world are the four components of a combination launch system.  Components that can be affordably built right now with existing materials and technology.       Four components that will give us an unlimited future.

In the closing lines of the film, it says,

“Maybe it’s a little early, maybe the time is not quite yet, but those are the worlds promising untold opportunity.  [They] beckon.  Silently they orbit the sun . . . . waiting.”

Why are we waiting?

 

Index of Articles

  1. Opening the High Frontier
  2. Skyhook, a Journey to Orbit and Beyond
  3. In the Beginning . . .
  4. Why do Rockets Cost so Much?
  5. Combination Launch Systems
  6. It’s All About Speed!
  7. Visions of the Future
  8. The Call of an Unlimited Future
  9. Combination Launch Systems, part 2
  10. Outward Bound: Beyond Low Earth Orbit
  11. and someday . . . Starships!
  12. Mars: how to get there
  13. Outpost Space Stations
  14. Dreams of Space
  15. The Moon or Mars?
  16. Skyhooks and Space Elevators

Visions of the Future

Where are we headed, as individuals, as a civilization?

What does the future hold in store for all of us?

Will we destroy ourselves in a nuclear war?

Will our civilization collapse due to overpopulation?

Will we muddle on with an ever growing divide between the haves and the have-nots?

Or will we take the next step and build a spacefaring civilization that sets no limits on what we might become?

We have been exploring space on a limited basis for over 50 years.  Limited because of the cost.  All the dreams and visions of large commercial passenger-carrying spaceships traveling between the planets, of cities on the Moon and Mars, of asteroid mining, and of space colonies scattered throughout the solar system, have remained dreams due to the high cost of spaceflight.  Isn’t it time we came up with a workable vision on how to make spaceflight affordable to everyone?  A vision that can be affordably built right now with existing technology?

Lunar City

Building a space transportation system that is affordable to everyone will allow us to make all of these dreams into reality.

cloud-city

Seriously, what other choice do we have?

The ideas and technologies that will make spaceflight affordable to everyone have existed for a long time.

The first component consists of choosing between air assisted launch or a ground assisted launch.  Two ideas that have been around for a long time.

The second component is making the launch vehicle reusable.

The third component is some form of a combination air-breathing and rocket motor propulsion system.

The fourth component is a non-rotating Skyhook with an ion propulsion system.

These four components, when used together, will reduce the cost of going to orbit from the current price of over $20 million per person to $20,000 per person.  And the best part of all this is that all four of these components can be affordably built with currently existing materials and technology, right now, today, no waiting.

 

Index of Articles

  1. Opening the High Frontier
  2. Skyhook, a Journey to Orbit and Beyond
  3. In the Beginning . . .
  4. Why do Rockets Cost so Much?
  5. Combination Launch Systems
  6. It’s All About Speed!
  7. Visions of the Future
  8. The Call of an Unlimited Future
  9. Combination Launch Systems, part 2
  10. Outward Bound: Beyond Low Earth Orbit
  11. and someday . . . Starships!
  12. Mars: how to get there
  13. Outpost Space Stations
  14. Dreams of Space
  15. The Moon or Mars?
  16. Skyhooks and Space Elevators

It’s All About Speed!

When a rocket takes off from the surface of the Earth and flies into orbit it increases its velocity by approximately 9,100 meters per second.  That breaks down to 7,800 meters per second for the speed of orbit and 1,300 meters per second for drag and gravity losses.  That is a lot of speed and it takes a lot of propellant to go that fast.

An example of just how much propellant is required is the Space Shuttle.  Sitting on the launch pad waiting to take-off, the Space Shuttle was 85% propellant, 14% launch vehicle, and 1% payload.  If Earth to orbit spaceflight is ever going to be affordable to everyone, the launch vehicle will need to be both fully reusable, and able to carry a large enough payload that it makes it worth all the trouble.  Up to now that has not been possible.  To make the Space Shuttle fully reusable it would have been necessary to make it both larger and heavier which would have required a larger propellant fraction and that would have made the payload go to zero.  Obviously, not a very workable solution.

This is where reducing the speed to orbit comes in.

There are a number of ways to do this.  One is to use a ground accelerator that is located on the side of a tall mountain to boost the launch vehicle up to 600 MPH before starting its engines.  This reduces the speed to orbit in two ways, by the speed added to the launch vehicle by the ground accelerator, and by reducing the drag and gravity losses that would have been incurred by the launch vehicle if it had accelerated to this speed and altitude on its own.

Another way to reduce the speed to orbit is to use a Skyhook at the upper end of the flight profile.  Skyhooks can be short or long.  The best way to use a Skyhook is to start small while the flight rate is low and gradually grow it into a longer and stronger version as demand increases.  For this example, a short Skyhook, like the one shown in this video was selected.

The total velocity reduction made possible by the 600 MPH ground accelerator and 200-kilometer long basic Skyhook used in this example is 1,060 meters per second.  This reduction in velocity will triple the amount of useful payload that can be delivered to the Skyhook compared to the same expendable launch vehicle flying to a space station without a ground accelerator or Skyhook.  Increasing the amount of useful payload by a factor of three will reduce the cost to orbit to 1/3 of what it was without the ground accelerator and Skyhook.  If it is assumed that the first stage of this launch vehicle is made reusable like the first stage of the Falcon 9, it then becomes reasonable to assume an additional 50% reduction in launch costs.  This will reduce the cost to orbit to 1/6 of the cost of flying the expendable version of this launch vehicle without the ground accelerator and Skyhook.

And this is only the beginning.  The longer the Skyhook becomes the lower the price becomes.  Once the Skyhook is long enough it then becomes possible to use a fully reusable single stage launch vehicle that will reduce the cost even more.  Best of all, the 600 MPH ground accelerator, the basic Skyhook, the reusable first stage launch vehicle, they can all be affordably built right now with existing materials and technology.

For more information about this and other related cost reducing concepts, read the book “Opening the High Frontier”.

 

Index of Articles

  1. Opening the High Frontier
  2. Skyhook, a Journey to Orbit and Beyond
  3. In the Beginning . . .
  4. Why do Rockets Cost so Much?
  5. Combination Launch Systems
  6. It’s All About Speed!
  7. Visions of the Future
  8. The Call of an Unlimited Future
  9. Combination Launch Systems, part 2
  10. Outward Bound: Beyond Low Earth Orbit
  11. and someday . . . Starships!
  12. Mars: how to get there
  13. Outpost Space Stations
  14. Dreams of Space
  15. The Moon or Mars?
  16. Skyhooks and Space Elevators

Combination Launch Systems

Combination launch systems are launch systems that use two or more different methods to accelerate a launch vehicle up to orbital velocity in order to reduce the cost of getting to orbit.

There are many different launch concepts that we can build today that can be combined together to do this: subsonic air-launch; supersonic air-launch; ground accelerators; combination air-breathing and rocket motor propulsion systems; reusable launch vehicles; and, Skyhooks.  All of these concepts can be combined together to reduce launch costs.

There are also many ways to combine these concepts to make a combination launch system.  They can be as simple as using a vertically oriented ground accelerator to boost an existing expendable launch vehicle up to 600 MPH prior to igniting the rocket motor.  They can be as complex as combining air-launch with a reusable launch vehicle that uses a combination ramjet, scramjet, rocket motor propulsion system, that flies to the lower end of a non-rotating Skyhook.  The hard part is finding the combination that has the lowest user cost to orbit for the lowest possible initial investment, that is sized for the existing launch market and has the potential to grow as the market grows.

Combination launch systems are not new.  The Wright brothers used a catapult to boost their first airplane up to flight speed.  The U. S. NAVY still uses catapults to launch fighter planes from the decks of aircraft carriers.  The world’s first reusable rocket plane, the Bell X-1, was air-launched from a B-29.  Probably the best-known combination lunch system was the X-15 rocket plane that was air-launched from a B-52.  In 1967 they even test flew a mock-up of a scramjet on the X-15.  There were also studies that examined the possibility of supersonic air-launching a rocket-ramjet-scramjet powered delta winged version of the X-15 from the back of the XB-70 at Mach 3 that had a small expendable upper stage rocket for carrying satellites into Earth orbit.

Unfortunately, all of these ideas fell by the wayside in our rush to beat the Russians to the Moon back in the 1960’s.  It wasn’t until SpaceShipOne flew in 2004, the start of Virgin Galactic and Stratolaunch shortly thereafter, as well as SpaceX and Blue Origin developing reusable first stage launch vehicles, that we have seen a serious effort to develop combination launch systems again.  The only negative about this is that none of these new combination lunch systems go far enough.

While all of these concepts, ground accelerators, air-launch, reusable first stage launch vehicles, air-breathing and rocket propulsion systems, and Skyhooks, will reduce the cost of getting to orbit, none of them, by themselves, will make spaceflight affordable to everyone.  To do that we will need a launch system that combines almost all of these concepts together.

Once we have that, the solar system is ours.

 

Index of Articles

  1. Opening the High Frontier
  2. Skyhook, a Journey to Orbit and Beyond
  3. In the Beginning . . .
  4. Why do Rockets Cost so Much?
  5. Combination Launch Systems
  6. It’s All About Speed!
  7. Visions of the Future
  8. The Call of an Unlimited Future
  9. Combination Launch Systems, part 2
  10. Outward Bound: Beyond Low Earth Orbit
  11. and someday . . . Starships!
  12. Mars: how to get there
  13. Outpost Space Stations
  14. Dreams of Space
  15. The Moon or Mars?
  16. Skyhooks and Space Elevators

Why do Rockets Cost so Much?

In the late 1960s and early 1970s, America used the Saturn V rocket to go to the Moon.  The first stage of that rocket had an empty weight of 130,000 kilograms and carried 2,160,000 kilograms of propellant.  It was used only once and then thrown away.

The second stage of the Saturn V had an empty weight of 40,100 kilograms and carried 456,100 kilograms of propellant.  Like the first stage, this stage was used only once and thrown away.

The third stage of the Saturn V had an empty weight of 13,300 kilograms and carried 106,600 kilograms of propellant.  This stage was also used once and thrown away.

The total empty weight of those three stages was 183,400 kilograms.

By comparison, a Boeing 747 has an empty weight of 183,000 kilograms. The 747 can fly 15 hours per day, 11 months per year, and has a useful life of 20 years.  It also carries three hundred plus passengers per flight.

Each Saturn V made only one flight and carried only three passengers.

This is why spaceflight that is based on using expendable rockets costs so much.

This is also why SpaceX and Blue Origin are working so hard to develop reusable rockets.

 

Index of Articles

  1. Opening the High Frontier
  2. Skyhook, a Journey to Orbit and Beyond
  3. In the Beginning . . .
  4. Why do Rockets Cost so Much?
  5. Combination Launch Systems
  6. It’s All About Speed!
  7. Visions of the Future
  8. The Call of an Unlimited Future
  9. Combination Launch Systems, part 2
  10. Outward Bound: Beyond Low Earth Orbit
  11. and someday . . . Starships!
  12. Mars: how to get there
  13. Outpost Space Stations
  14. Dreams of Space
  15. The Moon or Mars?
  16. Skyhooks and Space Elevators