Photonic Laser Propulsion to send a 100 kg vehicle to Mars in 3days and to get to wafercraft to 30% of the speed of light by 2035

Electrospray micropropulsion
http://web.mit.edu/aeroastro/labs/spl/research_ieps.htm

35 km/sec exhaust speeds.

Ultra thin wafer production
https://www.youtube.com/watch?v=fvrTVk9Ejqk

and their applications
http://www.sciencedirect.com/science...6112900671643X

A 40 micron thick electrospray rocket array that is 300 mm in diameter masses 364 grams and produces 1 micron-Newton per square meter a total of 7.2 kg across the entire surface, when illuminated with 1.2 MW of laser energy to accelerate 2 grams per second of propellant (either air or inert propellant on board) to 35 km/sec.

To fire a 5 kg rocket to the moon requires that the rocket attain 10.85 km/sec plus another 1.15 km/sec air drag and gravity losses. A total of 12.00 km/sec ideal delta vee. Another 2.3 km/sec is required to touch down softly on the lunar surface. A total of 14.3 km/sec. With a 35 km/sec exhaust speed, this means that 0.3354 of 5 kg is propellant. That is, 1,677 grams of the 5,000 gram take off weight is propellant. Adding in the 364 gram wafer this leaves 2,959 grams for useful payload on the moon!

At a distance of 384,400,000 meters - the distance from Earth to Moon, and using 330 nm

http://www.helpsavetheclimate.com/atmoswindows1.gif

we have

spot size = 384,400,000 meters * 1.22 * 330*10^(-9) / spot size

spot size = 12,440 mm diameter

http://proceedings.spiedigitallibrar...ticleid=856162
http://opticalengineering.spiedigita...icleid=1076017
https://www.youtube.com/watch?v=owVwjr6pTqc

A 12.44 m diameter paraboloid made of thin film plastics, masses 1,496 grams. The terrestrial counterpart must be much more massive - but is on the order of conventional telescopes. In fact, the power station and telescope can double as an observatory when not otherwise in use launching 5 kg payloads to the moon!

https://upload.wikimedia.org/wikiped...rors.svg.p ng

Subtracting 1,496 grams from the 2,959 grams available leaves 1,463 grams of useful material on the lunar surface.

The wafer at the focal point is good for accelerating the payload toward the moon and away from Earth with a beam arriving from Earth. But the large diameter isn't needed near Earth, but near the moon. So, the inflatable optics consist of two stages that are deployed sequentially.

The system operating near the moon is a Cassegrain system.

https://en.wikipedia.org/wiki/Casseg...segrain.en.png

With the main mirror facing Earth, a secondary mirror facing the rocket array, and the rocket array itself located in the main mirror's body. Surrounding the microthruster array is a ring of fresnel reflectors that focus sunlight on to the secondary mirror arriving from the back of the vehicle.

So, during ascent, the light is focused on the 1.2 meter diameter fresnel lens annulus, which focuses the laser energy arriving from Earth on to the secondary, which then illuminates the engine array at the focal point, which then powers the microthruster array pointing back toward the laser beam. The main primary is not used. During descent to the lunar surface, the rocket array is flipped over to point at the moon and the 12.44 meter diameter primary is pointed back at Earth, and the laser beam. The beam arrives and is focused on the secondary, which focuses the energy on the engine array, powering it.

The system is filled with 8.2 kg of hydrogen gas at sea level and is released. It rises to 20 km altitude, outgassing until it holds 1,677 grams of gas at altitude. It is found by the terrestrial laser beam which energises the rocket array. The vehicle begins acceleration at 1.44 gees and rises to 2.08 gees and achieves 10.85 km/sec after traversing 3,410 km to the moon. As the vehicle ascends to the moon it slows, during the 3 day journey. Over this period, communications is maintained by the laser beam. The system flips over as it approaches the moon. Guidance is provided by off axis thrust at lower power than the 1.2 MW used during lift off. At 140 km above the lunar surface, the beam is turned on full power as the vehicle main mirror faces earth and the rocket array faces the lunar surface. It accelerates at 2 gees until it touches down on the lunar surface.

1,463 grams of useful material - 3.2 lbs - is delivered to the moon.

The dish receives 1.2 MW from Earth. It is also capable, with slight modification, capable of receiving 120,000 Watts from the Sun, when it is in the sky.

12 MJ is required to vaporise rocks and 3.3 kg of rocks are needed to produce 1.0 kg of useful material. So, 40 MJ is needed to process 1 kg of useful materials. Starting with 1.2 MW 33.3 kg per second of material may be produced from 111.1 kg of lunar regolith.

A machine cell 230 microns in diameter made of silicene (a silicon equivalent of graphene) that is 6 microns thick, masses only 2.2 micro grams and intercepts 50 microwatts of power from sunlight, or 250 microwatts, if in the 1.2 MW laser beam from Earth. 88 millijoules is required to replicate a machine cell of these dimensions, and it takes 1/2 hour self replication time.

Total amount of machine cells increases by 33.3 kg per second from the laser energy - but after six hours, this represents less than 1% of the total output of the self-replicating system, with over 238,000 tons of machine cells spreading out from the landing point.

To avoid negative attention, one must take care to understand the albedo at each point on the lunar surface, and faithfully reproduce that albedo across the coating of machine cells. Since only 12% of the incident light on the solar surface is reflected, and since 80% solar efficiencies have been achieved in solar cells, its easy to see that the system can soak up as much sunlight as it can, and still maintain the same levels of brightness for distant observars as the native landscape. Laser contact is maintained to maintain contact with the growing network of self replicating machine cells.

The moon's radius is 1,737,190 meters. When fully covered with machine cells, the moon system processes 259,394 metric tons per second using sunlight alone. This is 1,106 metric tons for every man woman and child on Earth each year! Materials such as lithium-6 and deuterium, which can be used to support Jetter cycle fusion, or thorium, or uranium, which can be used to make fission reactors, can substantially increase production rates.

Aneutronic micro-fusion has the potential to allow this system to transform worlds in very short time periods.

A six kilometer long cylinder that is 6 kilometers in diameter inside an 8.5 km pressure sphere, with its central axis of rotation normal to the lunar surface, with sawtooth like hills along the surface angled at 9.594 degrees from the rotational plane, 60 foot wide strips with 6.56 foot steps - moving at 617 kph completing a rotation once every 3.7 minutes, maintains one gee on the interior of the cylinder. An LED ceiling 30 meters above the interior of the cylinder, forms an artificial sky, and maintains calm conditions on the cylinder.

http://images.inmagine.com/400nwm/ir...tg01401801.jpg

6 km diameter implies 18.84 km circumference and with a 6 km height, totals 113 sq km of one gee area. At 16,000 people per sq km we have 1.8 million inhabitants. The base of the cylinder rests on a maglev bearing that maintains speed. A series of 285 belts each 800 mm wide and changing angle relative to the cylinder's surface, to maintain normal gee forces ending at zero speed 228 meters from the bottom edge - at 1/6 gee. 4,114 of these cylinders built on the moon support 7.4 billion persons at very high living standards. This covers an area 128,261 sq km.

With orbiting solar pumped lasers in GEO and at L4 and L5, that have objectives of 12.5 km and operate at hundreds of gigawatts, we can form beams at Earth that are only a centimeter across, and can lift 700 tons! The size of a typical superyacht, or airliner.

http://www.superyachttimes.com/yacht...acht-gazzella/

https://www.youtube.com/watch?v=NVItPJAu_Fk

This can lift a dozen people to 900 people at a time off world, depending on the nature of transport.

Instead of a 50 meter long 9 meter diameter cylindrical cabin, we can imagine a 30 meter diameter disk with a similar floor area to the cabin.

4,114 cities on the moon, each with 1.8 million inhabitants, each with 100 passenger transports each with 900 seat capacity, deliver 1.8 million people per year per city.