Manned Venus Flight using Chemical Rockets.

Yes, Venus with chemical rockets

With an escape velocity nearly equal to that of Earth, it was thought that manned flight to Venus that incorporated a landing on the planet would not be possible, since multi-stage flight would be required. However, it is possible to send multi-stage elements to Venus and refuel them there using abundant solar power and materials extracted from the Venusian atmosphere.

Radiation Suit

I recently posted that a powered hardshell suit made of 2.6 cm of tungsten, massing 880 kg would provide more than adequate shielding for long-term interplanetary flight. This suit when coated with ceramic insulator and equipped with appropriate refrigeration would be quite capable of operating on the Venusian surface.

Suspended Animation

I also pointed out that Dr. Mark Roth has developed a method of invoking suspended animation that is very efficient and had no upper limit. The process is in human trials and being used every day to save lives in trauma units. The biochemistry is very similar to what goes on in hibernation and appears to be capable of producing decades long stasis at low risk that is usable multiple times.

MEMS based systems highly reliable

I've said too that micro-electro-mechanical systems (MEMS) based equipment, which today is used in digital light projectors, accelerometers, inertial guidance systems, ink jet printers, plasma displays, and a host of other every day products, are readily adapted to producing rocket arrays capable of producing 340 kPascals of pressure very safely and reliably as well as use in highly redundant, very efficient and reliable life support processes and fuel cells, and other systems, achieving very high performance per unit weight.

Flight weight very low

As a result a very capable system massing only 2,500 kg may support a one man interplanetary scout ship using chemical hydrogen oxygen rockets.

Typical flight to Venus and Back

Consider the flight opportunity leaving Earth for Venus on 3/24/2017. Hyperbolic excess velocity of 4.43 km/sec. Arrival at Mars on 9/9/2017 with a hyperbolic excess velocity of 9.81 km/sec. A stop over of 90 days and departure to Earth on 1/12/2018 with a hyperbolic excess velocity of 3.22 km/sec arriving back at earth on 5/4/2018 with a hyperbolic excess velocity of 2..86 km/sec.

Venus escape velocity is 10.36 km/sec
Earth escape velocity is 11.19 km/sec

That means that departing Earth the payload must have a speed of

sqrt(11.19^2+4.43^2) = 12.04 km/sec + 1.61 km/sec ascent loss = 13.65 km/sec

Arriving at Venus the payload arrives at the top of the Venusian atmosphere with a speed of

sqrt(10.36^2 + 9.81^2) = 14.27 km/sec

Which is about 10 km/sec less than Galileo navigated through Jupiter's atmosphere a few decades ago.

Departing Venus the payload must have a speed of

sqrt(10.36^2 + 3.22^2) = 10.85 km/sec

Arriving at Earth the payload arrives at the top of Earth's atmosphere with a speed of

sqrt(11.19^2 + 2.85^2) = 11.55 km/sec

Chemical Rocket Requirements - 3 Stages

Now with a 4.2 km/sec exhaust speed for a hydrogen oxygen rocket and a 7% structural fraction, we can compute the following for a 2,500 kg payload and a 3 stage rocket;

14.27 / 3 = 4.76 km/sec per stage

u = 1 - 1/exp(4.76/4.20) = 0.6781 propellant fraction

1.0000 - 0.6781 - 0.0700 = 0.2519 payload fraction

2,500.0 kg / 0.2519 = 9,924.6 kg - stage weight
9,924.6 kg * 0.0700 = 694.7 kg - structure weight
9,924.6 kg * 0.6781 = 6,729.9 kg - propellant weight

9,924.6 kg / 0.2519 = 39,398.9 kg - stage weight
30,398.9 kg * 0.0700 = 2,757.9 kg - structure weight
30,398.9 kg * 0.6781 = 26,716.4 kg - propellant weight

30,398.9 kg / 0.2519 = 156,406.8 kg - take off weight
156,406.8 kg * 0.0700 = 10,948.5 kg - structure weight
156,406.8 kg * 0.6781 = 106,059.4 kg - propellant weight

Converting 3 Stages to 7 Identical Flight Elements

Now if we take 2,500 away from 156,406.8 we obtain 153,906.8 kg. If we then divide the total by 7 we obtain 21,986.6 kg. Then we have

21,986.6 * 0.0700 = 1,539.0 kg - structure weight
21,986.6 * 0.9300 = 20,447.6 kg - propellant weight

Now consider 7 elements, each equipped with an aerospike engine, and cross feeding, along the lines describe here;

http://www.scribd.com/doc/45631474/S...rived-Launcher

Here is what the system is capable of;

1,539.0 kg - Element Structure
20,447.6 kg - Element Propellant
21,986.6 kg - Element Total

2,500.0 kg - Payload

156,406.2 kg Take off Weight
68,459.8 kg Stage 2 Weight
24,486.6 kg Stage 3 Weight

81,790.4 kg Four Propellant Tanks
40,895.2 kg Two Propellant Tanks
20,447.6 kg One Propellant Tank

0.5229 First Stage Propellant Fraction
0.5974 Second Stage Propellant Fraction
0.8351 Third Stage Propellant Fraction

3.11 km/sec First Stage Speed
3.82 km/sec Second Stage Speed
7.57 km/sec Third Stage Speed

3.11 km/sec First Stage Total Speed
6.93 km/sec Second Stage Total Speed
14.50 km/sec Third Stage Total Speed

In fact, 2,725 kg of payload in combination with the third stage element can be projected from Earth with the requisite excess velocity.

Sending 7 Flight Elements to Venus

Now one interesting thing is that all the flight elements are the same shape, same weight, and same capabilities. They are very much like the Space Shuttle External Tank, but instead of carrying 710 metric tons of propellant they are carrying only 20.5 metric tons of propellant and are thus only 30..7% the size of the External Tank. That is a tank 2.6 m in diameter and 14..4 m long.

So, imagine that seven third stage elements are projected to Venus all at the same time, with seven separate launches within the launch window.

So, we have seven flight elements on their way to Venus. Six of which are carrying 2,725 kg of excess propellant and one of which is carrying a 2,500 kg payload and 225 kg of excess propellant.

Using the Venusian Atmosphere as Propellant Supply

They all arrive at Venus and execute an aerobraking manoeuvre high in the Venusian atmosphere.

Operating at 58 km.

In addition to inflatable wings these elements are equipped with balloons! These deploy once the vehicle slows to subsonic speed high in the Venusian atmosphere. The act like drogue chutes as they deploy. They are then filled with hydrogen gas, evaporated from the propellant carried along on the voyage.

Venusian Atmosphere

The Venusian atmosphere has the following characteristics;

KM C Pressure Density
0 462 92.10 65.592 kg/m3
5 424 66.65 50.604 kg/m3
10 385 47.39 38.114 kg/m3
15 348 33.04 28.156 kg/m3
20 306 22.52 20.583 kg/m3
25 264 14.93 14.713 kg/m3
30 222 9.851 10.532 kg/m3
35 180 5.917 6.912 kg/m3
40 143 3.501 4.454 kg/m3
45 110 1.979 2.734 kg/m3
50 75 1.066 1.621 kg/m3
55 27 0.5314 0.937 kg/m3
60 -10 0.2357 0.474 kg/m3
65 -30 0.09765 0.213 kg/m3
70 -43 0.03690 0.085 kg/m3

Solar Power on Venus

Venus is closer to the Sun and rotates very slowly. So, its easy to choose a landing site that's in constant sunlight, if one remains above the cloud layer on the planet.

The balloons are transparent and contain a 37 m diameter thin film reflector that focuses light. The reflector focuses light on to a solar pumped laser which beams energy via an optical fibre to a high intensity photovoltaic power unit only 200 mm in diameter. This tiny lightweight device produces 1.55 MW of electrical power which is used to process the Venusian atmosphere separating out the water vapour which occurs at 20 ppm concentration.

The water when obtained is then decomposed into hydrogen and oxygen and used to refill the empty propellant tanks with 2,921.1 kg of hydrogen and 17,526.5 kg of oxygen made from 26,289.8 kg of water vapour recovered from 1.32 million tonnes of Venusian atmosphere, releasing 5,842.2 kg of excess oxygen since the rockets run hydrogen rich. Some of this oxygen is used for breathing.

Since the sun shines continuously high above the Venusian atmosphere during the term of the vehicle's stay on the planet, only 100,000 Watts of power is needed to break this water down to its component gases and liquefy them. Another 300,000 watts is needed to process the 169 litres of Venusian atmosphere per second and extract the 292.1 litres per day of water vapour from it and break it down into its component gases.

With a capacity of 1.55 MW each system may produce up to 4x the amounts of propellant needed to refill the flight elements with propellant from the Venusian atmosphere in this way in less than 23 days after arrival. Thereafter, extra propellant is provided to operate a fuel cell powered quad rotor designed to fly to the Venusian surface carrying the traveller in their high pressure refrigerated and highly insulated powered tungsten hard suit and return them to their 'nest' floating high above the Venusian surface.

The 37 m diameter balloon occupies 26,672 cubic meters when fully inflated. Immediately following arrival at Venus the system floats at an altitude of 65 km. As each of the seven flight elements fill, they sink in the atmosphere to an altitude of 55 km.

All seven elements are equipped with thrusters. They use these to navigate to remain near to one another. After they are filled with propellant, they have the ability to navigate very near to one another, adjust their buoyancy to control altitude precisely. When within distance, they fire automated mooring lines at each other, pick them up with automated bollards and grips, and draw themselves together. When together in this way they mechanically link to one another, and deploy cross-feed lines.

The system is now ready to retract their balloons and operate as a three stage launcher on Venus.

The seven elements then fire in a manner similar to that used to depart Earth, with only the piloted element leaving the Venusian system. The other six flight elements re-enter the Venusian atmosphere, and deploy their balloons again to refill and repeat their operation. In this way, follow on flights only need involve the launch of a single explorer since the other six element will already be on Venus provisioned and ready to go.

High Pressure Hard Shell Suit

The atmospheric diving suit has a long history and is capable of operating at 610 m depths on Earth. This is a pressure of 61.5 atm. The same pressure as 6km above the surface of Venus. This technology when extended to 91.1 atm - about 900 meter depth for ocean diving - equals the pressures needed for Venus.

http://en.wikipedia.org/wiki/Atmospheric_diving_suit

In addition to pressure temperatures of 462 C must be withstood as well. This is achieved by incorporating layers of evacuated silicon carbide aerogels which have a very high resistance to heat transfer.

http://en.wikipedia.org/wiki/File:Ae...r_filtered.jpg

A 2.6 mm thick layer of aerogel of this type creates an inert coating over the tungsten layer and bonds easily with it and is quite stable at pressures and temperatures found on Venus' surface.

Similar systems of ceramic coated metals are used in high temperature piping by industry today in far harsher environments than found on Venus.

For a typical suit 945 watts must be removed from the system. The refrigerator maintains 18-24 C internally and rejects up to 1,200 Watts to a radiator that operates at 800 C on the users backpack.

Sufficient propellant is brought down to Venusian surface to maintain life support for 48 hours of surface operations. The Quadrotor takes 45 minutes to drop from altitude and two hours to climb back to altitude. 26 mm of aerogel are needed to insulate cryogenic gases, the rate of the use of these limits the stay times on the surface. Waste water is kept and recycled on board the spacecraft once altitude is regained.

With intense sunlight available nearly all the time, sunlight may be converted to a spectrum of colors using solar pumped lasers to illuminate crops through optical fibres. In this way, 6x the crops may be grown per unit of collector area than is grown on aeroponic systems today.

Quadrotors operating automatically on the Surface of Venus to extract materials which are then processed at the atomic scale with laser systems that vaporize rock, and use electrostatic fields to separate them by atomic weight, to then be recombined into any useful material and assembled using additive manufacturing - products can be made from the Venusian surface materials. This includes aerial cities as well as compact aerial farms. All of which operate in the CO2 atmosphere at an altitude of 58 km where the atmosphere is room temperature and 1 bar.

http://www.scribd.com/doc/121742582/Aerial-Farms

http://www.youtube.com/watch?v=MvRTALJp8DM

http://www.youtube.com/watch?v=geqip_0Vjec

http://www.youtube.com/watch?v=xvN9Ri1GmuY

Thus, during the interval between visits the six remaining booster elements may be equipped with hardware that allows the construction of significant infrastructure between flights - which is an interval of about 584 days for minimum energy trajectories.

http://www.youtube.com/watch?v=d7_3PDnihMg

http://www.youtube.com/watch?v=p9Jl3MJh0lI

http://www.dailymail.co.uk/sciencete...--warfare.html

There is a lot of calculation there to review in a Usenet post.
Perhaps you should create a blog that collected your various
proposals.
The titanium spacesuit has the problem that it would be very
unwieldly to move around in even in zero-g for missions several months
long. And on a world such as Venus with gravity close to Earth it
would be virtually impossible even for short periods.
Here's another solution, just make the missions shorter. In the
debate about whether our next destination in space should be the Moon,
Mars, or an asteroid, a key factor that needs to be kept in mind is
that setting up a base first on the Moon would allow us to produce
virtually unlimited propellant to be placed orbit. This could make
interplanetary flights much shorter.
Try this calculation: say you used two or three shuttle ET sized
hydrolox stages and a habitation module say of size of Bigelow's
Sundancer, about 8.6 metric tons. How long would it take to make a
mission to Mars?

Bob Clark

On Jun 7, 10:23*am, wrote:
Yes, Venus with chemical rockets

With an escape velocity nearly equal to that of Earth, it was thought that manned flight to Venus that incorporated a landing on the planet would not be possible, since multi-stage flight would be required. *However, it is possible to send multi-stage elements to Venus and refuel them there using abundant solar power and materials extracted from the Venusian atmosphere..

Radiation Suit

I recently posted that a powered hardshell suit made of 2.6 cm of tungsten, massing 880 kg would provide more than adequate shielding for long-term interplanetary flight. *This suit when coated with ceramic insulator and equipped with appropriate refrigeration would be quite capable of operating on the Venusian surface.

Suspended Animation

I also pointed out that Dr. Mark Roth has developed a method of invoking suspended animation that is very efficient and had no upper limit. *The process is in human trials and being used every day to save lives in trauma units. *The biochemistry is very similar to what goes on in hibernation and appears to be capable of producing decades long stasis at low risk that is usable multiple times.

MEMS based systems highly reliable

I've said too that micro-electro-mechanical systems (MEMS) based equipment, which today is used in digital light projectors, accelerometers, inertial guidance systems, ink jet printers, plasma displays, and a host of other every day products, are readily adapted to producing rocket arrays capable of producing 340 kPascals of pressure very safely and reliably as well as use in highly redundant, very efficient and reliable life support processes and fuel cells, and other systems, achieving very high performance per unit weight.

Flight weight very low

As a result a very capable system massing only 2,500 kg may support a one man interplanetary scout ship using chemical hydrogen oxygen rockets.

Typical flight to Venus and Back

Consider the flight opportunity leaving Earth for Venus on 3/24/2017. *Hyperbolic excess velocity of 4.43 km/sec. *Arrival at Mars on 9/9/2017 with a hyperbolic excess velocity of 9.81 km/sec. *A stop over of 90 days and departure to Earth on 1/12/2018 with a hyperbolic excess velocity of 3.22 km/sec arriving back at earth on 5/4/2018 with a hyperbolic excess velocity of 2.86 km/sec.

Venus escape velocity is 10.36 km/sec
Earth escape velocity is 11.19 km/sec

That means that departing Earth the payload must have a speed of

* *sqrt(11.19^2+4.43^2) = 12.04 km/sec + 1.61 km/sec ascent loss = 13.65 km/sec

Arriving at Venus the payload arrives at the top of the Venusian atmosphere with a speed of

* sqrt(10.36^2 + 9.81^2) = 14.27 km/sec

Which is about 10 km/sec less than Galileo navigated through Jupiter's atmosphere a few decades ago.

Departing Venus the payload must have a speed of

*sqrt(10.36^2 + 3.22^2) = 10.85 km/sec

Arriving at Earth the payload arrives at the top of Earth's atmosphere with a speed of

* sqrt(11.19^2 + 2.85^2) = 11.55 km/sec

Chemical Rocket Requirements - 3 Stages

Now with a 4.2 km/sec exhaust speed for a hydrogen oxygen rocket and a 7% structural fraction, we can compute the following for a 2,500 kg payload and a 3 stage rocket;

* *14.27 / 3 = 4.76 km/sec per stage

* *u = 1 - 1/exp(4.76/4.20) = 0.6781 propellant fraction

* *1.0000 - 0.6781 - 0.0700 = 0.2519 payload fraction

* *2,500.0 kg / 0.2519 = 9,924.6 kg - stage weight
* *9,924.6 kg * 0.0700 = * 694.7 kg - structure weight
* *9,924.6 kg * 0.6781 = 6,729.9 kg - propellant weight

* * 9,924.6 kg / 0.2519 = 39,398.9 kg - stage weight
* *30,398.9 kg * 0.0700 = *2,757.9 kg - structure weight
* *30,398.9 kg * 0.6781 = 26,716.4 kg - propellant weight

* *30,398.9 kg / 0.2519 = 156,406.8 kg - take off weight
* 156,406.8 kg * 0.0700 = *10,948.5 kg - structure weight
* 156,406.8 kg * 0.6781 = 106,059.4 kg - propellant weight

Converting 3 Stages to 7 Identical Flight Elements

Now if we take 2,500 away from 156,406.8 we obtain 153,906.8 kg. *If we then divide the total by 7 we obtain 21,986.6 kg. *Then we have

* *21,986.6 * 0.0700 = *1,539.0 kg - structure weight
* *21,986.6 * 0.9300 = 20,447.6 kg - propellant weight

Now consider 7 elements, each equipped with an aerospike engine, and cross feeding, along the lines describe here;

http://www.scribd.com/doc/45631474/S...rived-Launcher

Here is what the system is capable of;

*1,539.0 kg - Element Structure
20,447.6 kg - Element Propellant
21,986.6 kg - Element Total

*2,500.0 kg - Payload

156,406.2 kg Take off Weight
*68,459.8 kg Stage 2 Weight
*24,486.6 kg Stage 3 Weight

*81,790.4 kg Four Propellant Tanks
*40,895.2 kg Two Propellant Tanks
*20,447.6 kg One Propellant Tank

0.5229 First Stage Propellant Fraction
0.5974 Second Stage Propellant Fraction
0.8351 Third Stage Propellant Fraction

3.11 km/sec First Stage Speed
3.82 km/sec Second Stage Speed
7.57 km/sec Third Stage Speed

*3.11 km/sec First Stage Total Speed
*6.93 km/sec Second Stage Total Speed
14.50 km/sec Third Stage Total Speed

In fact, 2,725 kg of payload in combination with the third stage element can be projected from Earth with the requisite excess velocity.

Sending 7 Flight Elements to Venus

Now one interesting thing is that all the flight elements are the same shape, same weight, and same capabilities. *They are very much like the Space Shuttle External Tank, but instead of carrying 710 metric tons of propellant they are carrying only 20.5 metric tons of propellant and are thus only 30.7% the size of the External Tank. *That is a tank 2.6 m in diameter and 14.4 m long.

So, imagine that seven third stage elements are projected to Venus all at the same time, with seven separate launches within the launch window.

So, we have seven flight elements on their way to Venus. *Six of which are carrying 2,725 kg of excess propellant and one of which is carrying a 2,500 kg payload and 225 kg of excess propellant.

Using the Venusian Atmosphere as Propellant Supply

They all arrive at Venus and execute an aerobraking manoeuvre high in the Venusian atmosphere.

Operating at 58 km.

In addition to inflatable wings these elements are equipped with balloons! *These deploy once the vehicle slows to subsonic speed high in the Venusian atmosphere. *The act like drogue chutes as they deploy. *They are then filled with hydrogen gas, evaporated from the propellant carried along on the voyage.

Venusian Atmosphere

The Venusian atmosphere has the following characteristics;

KM * * C * * * Pressure * Density
0 * * * 462 * * 92.10 * 65.592 kg/m3
5 * * * 424 * * 66.65 * 50.604 kg/m3
10 * * *385 * * 47.39 * 38.114 kg/m3
15 * * *348 * * 33.04 * 28.156 kg/m3
20 * * *306 * * 22.52 * 20.583 kg/m3
25 * * *264 * * 14.93 * 14.713 kg/m3
30 * * *222 * * 9.851 * 10.532 kg/m3
35 * * *180 * * 5.917 * *6.912 kg/m3
40 * * *143 * * 3.501 * *4.454 kg/m3
45 * * *110 * * 1.979 * *2.734 kg/m3
50 * * *75 * * *1.066 * *1.621 kg/m3
55 * * *27 * * *0.5314 * 0.937 kg/m3
60 * * *-10 * * 0.2357 * 0.474 kg/m3
65 * * *-30 * * 0.09765 *0.213 kg/m3
70 * * *-43 * * 0.03690 *0.085 kg/m3

Solar Power on Venus

Venus is closer to the Sun and rotates very slowly. *So, its easy to choose a landing site that's in constant sunlight, if one remains above the cloud layer on the planet.

The balloons are transparent and contain a 37 m diameter thin film reflector that focuses light. *The reflector focuses light on to a solar pumped laser which beams energy via an optical fibre to a high intensity photovoltaic power unit only 200 mm in diameter. *This tiny lightweight device produces 1.55 MW of electrical power which is used to process the Venusian atmosphere separating out the water vapour which occurs at 20 ppm concentration.

The water when obtained is then decomposed into hydrogen and oxygen and used to refill the empty propellant tanks with 2,921.1 kg of hydrogen and 17,526.5 kg of oxygen made from 26,289.8 kg of water vapour recovered from 1.32 million tonnes of Venusian atmosphere, releasing 5,842.2 kg of excess oxygen since the rockets run hydrogen rich. *Some of this oxygen is used for breathing.

Since the sun shines continuously high above the Venusian atmosphere during the term of the vehicle's stay on the planet, only 100,000 Watts of power is needed to break this water down to its component gases and liquefy them. *Another 300,000 watts is needed to process the 169 litres of Venusian atmosphere per second and extract the 292.1 litres per day of water vapour from it and break it down into its component gases.

With a capacity of 1.55 MW each system may produce up to 4x the amounts of propellant needed to refill the flight elements with propellant from the Venusian atmosphere in this way in less than 23 days after arrival. *Thereafter, extra propellant is provided to operate a fuel cell powered quad rotor designed to fly to the Venusian surface carrying the traveller in their high pressure refrigerated and highly insulated powered tungsten hard suit and return them to their 'nest' floating high above the Venusian surface.

The 37 m diameter balloon occupies 26,672 cubic meters when fully inflated. Immediately following arrival at Venus the system floats at an altitude of 65 km. *As each of the seven flight elements fill, they sink in the atmosphere to an altitude of 55 km.

All seven elements are equipped with thrusters. *They use these to navigate to remain near to one another. *After they are filled with propellant, they have the ability to navigate very near to one another, adjust their buoyancy to control altitude precisely. When within distance, they fire automated mooring lines at each other, pick them up with automated bollards and grips, and draw themselves together. *When together in this way they mechanically link to one another, and deploy cross-feed lines.

The system is now ready to retract their balloons and operate as a three stage launcher on Venus.

The seven elements then fire in a manner similar to that used to depart Earth, with only the piloted element leaving the Venusian system. *The other six flight elements re-enter the Venusian atmosphere, and deploy their balloons again to refill and repeat their operation. *In this way, follow on flights only need involve the launch of a single explorer since the other six element will already be on Venus provisioned and ready to go.

High Pressure Hard Shell Suit

The atmospheric diving suit has a long history and is capable of operating at 610 m depths on Earth. *This is a pressure of 61.5 atm. *The same pressure as 6km above the surface of Venus. *This technology when extended to 91.1 atm - about 900 meter depth for ocean diving - equals the pressures needed for Venus.

http://en.wikipedia.org/wiki/Atmospheric_diving_suit

In addition to pressure temperatures of 462 C must be withstood as well. *This is achieved by incorporating layers of evacuated silicon carbide aerogels which have a very high resistance to heat transfer.

http://en.wikipedia.org/wiki/File:Ae...r_filtered.jpg

A 2.6 mm thick layer of aerogel of this type creates an inert coating over the tungsten layer and bonds easily with it and is quite stable at pressures and temperatures found on Venus' surface.

Similar systems of ceramic coated metals are used in high temperature piping by industry today in far harsher environments than found on Venus.

For a typical suit 945 watts must be removed from the system. *The refrigerator maintains 18-24 C internally and rejects up to 1,200 Watts to a radiator that operates at 800 C on the users backpack.

Sufficient propellant is brought down to Venusian surface to maintain life support for 48 hours of surface operations. *The Quadrotor takes 45 minutes to drop from altitude and two hours to climb back to altitude. *26 mm of aerogel are needed to insulate cryogenic gases, the rate of the use of these limits the stay times on the surface. *Waste water is kept and recycled on board the spacecraft once altitude is regained.

With intense sunlight available nearly all the time, sunlight may be converted to a spectrum of colors using solar pumped lasers to illuminate crops through optical fibres. *In this way, 6x the crops may be grown per unit of collector area than is grown on aeroponic systems today.

Quadrotors operating automatically on the Surface of Venus to extract materials which are then processed at the atomic scale with laser systems that vaporize rock, and use electrostatic fields to separate them by atomic weight, to then be recombined into any useful material and assembled using additive manufacturing - products can be made from the Venusian surface materials. *This includes aerial cities as well as compact aerial farms. *All of which operate in the CO2 atmosphere at an altitude of 58 km where the atmosphere is room temperature and 1 bar.

http://www.scribd.com/doc/121742582/Aerial-Farms

http://www.youtube.com/watch?v=MvRTALJp8DM

http://www.youtube.com/watch?v=geqip_0Vjec

http://www.youtube.com/watch?v=xvN9Ri1GmuY

Thus, during the interval between visits the six remaining booster elements may be equipped with hardware that allows the construction of significant infrastructure between flights - which is an interval of about 584 days for minimum energy trajectories.

http://www.youtube.com/watch?v=d7_3PDnihMg

http://www.youtube.com/watch?v=p9Jl3MJh0lI

http://www.dailymail.co.uk/sciencete...The-astonishin...

Good points. The suit is powered and equipped with sensors to drive the suit in a natural way. It has millions of degrees of freedom since it is produced by 3D printing technology. For these reasons its easy to wear. It is designed from the outset for long duration wear including things like an LED/optical fibre tanning capability among others.

http://www.youtube.com/watch?v=iNpbLRrdJxQ

http://www.youtube.com/watch?v=hf_rf6bGvhw

http://www.youtube.com/watch?v=BUUNt_N48EQ

http://www.youtube.com/watch?v=E7--ZWPVVdQ

On Saturday, June 8, 2013 3:19:19 AM UTC+12, Robert Clark wrote:
There is a lot of calculation there to review in a Usenet post.

Perhaps you should create a blog that collected your various

proposals.

The titanium spacesuit has the problem that it would be very

unwieldly to move around in even in zero-g for missions several months

long. And on a world such as Venus with gravity close to Earth it

would be virtually impossible even for short periods.

Here's another solution, just make the missions shorter. In the

debate about whether our next destination in space should be the Moon,

Mars, or an asteroid, a key factor that needs to be kept in mind is

that setting up a base first on the Moon would allow us to produce

virtually unlimited propellant to be placed orbit. This could make

interplanetary flights much shorter.

Try this calculation: say you used two or three shuttle ET sized

hydrolox stages and a habitation module say of size of Bigelow's

Sundancer, about 8.6 metric tons. How long would it take to make a

mission to Mars?



Bob Clark



On Jun 7, 10:23*am, wrote:

Yes, Venus with chemical rockets



With an escape velocity nearly equal to that of Earth, it was thought that manned flight to Venus that incorporated a landing on the planet would not be possible, since multi-stage flight would be required. *However, it is possible to send multi-stage elements to Venus and refuel them there using abundant solar power and materials extracted from the Venusian atmosphere.



Radiation Suit



I recently posted that a powered hardshell suit made of 2.6 cm of tungsten, massing 880 kg would provide more than adequate shielding for long-term interplanetary flight. *This suit when coated with ceramic insulator and equipped with appropriate refrigeration would be quite capable of operating on the Venusian surface.



Suspended Animation



I also pointed out that Dr. Mark Roth has developed a method of invoking suspended animation that is very efficient and had no upper limit. *The process is in human trials and being used every day to save lives in trauma units. *The biochemistry is very similar to what goes on in hibernation and appears to be capable of producing decades long stasis at low risk that is usable multiple times.



MEMS based systems highly reliable



I've said too that micro-electro-mechanical systems (MEMS) based equipment, which today is used in digital light projectors, accelerometers, inertial guidance systems, ink jet printers, plasma displays, and a host of other every day products, are readily adapted to producing rocket arrays capable of producing 340 kPascals of pressure very safely and reliably as well as use in highly redundant, very efficient and reliable life support processes and fuel cells, and other systems, achieving very high performance per unit weight.



Flight weight very low



As a result a very capable system massing only 2,500 kg may support a one man interplanetary scout ship using chemical hydrogen oxygen rockets.



Typical flight to Venus and Back



Consider the flight opportunity leaving Earth for Venus on 3/24/2017. *Hyperbolic excess velocity of 4.43 km/sec. *Arrival at Mars on 9/9/2017 with a hyperbolic excess velocity of 9.81 km/sec. *A stop over of 90 days and departure to Earth on 1/12/2018 with a hyperbolic excess velocity of 3.22 km/sec arriving back at earth on 5/4/2018 with a hyperbolic excess velocity of 2.86 km/sec.



Venus escape velocity is 10.36 km/sec

Earth escape velocity is 11.19 km/sec



That means that departing Earth the payload must have a speed of



* *sqrt(11.19^2+4.43^2) = 12.04 km/sec + 1.61 km/sec ascent loss = 13.65 km/sec



Arriving at Venus the payload arrives at the top of the Venusian atmosphere with a speed of



* sqrt(10.36^2 + 9.81^2) = 14.27 km/sec



Which is about 10 km/sec less than Galileo navigated through Jupiter's atmosphere a few decades ago.



Departing Venus the payload must have a speed of



*sqrt(10.36^2 + 3.22^2) = 10.85 km/sec



Arriving at Earth the payload arrives at the top of Earth's atmosphere with a speed of



* sqrt(11.19^2 + 2.85^2) = 11.55 km/sec



Chemical Rocket Requirements - 3 Stages



Now with a 4.2 km/sec exhaust speed for a hydrogen oxygen rocket and a 7% structural fraction, we can compute the following for a 2,500 kg payload and a 3 stage rocket;



* *14.27 / 3 = 4.76 km/sec per stage



* *u = 1 - 1/exp(4.76/4.20) = 0.6781 propellant fraction



* *1.0000 - 0.6781 - 0.0700 = 0.2519 payload fraction



* *2,500.0 kg / 0.2519 = 9,924.6 kg - stage weight

* *9,924.6 kg * 0.0700 = * 694.7 kg - structure weight

* *9,924.6 kg * 0.6781 = 6,729.9 kg - propellant weight



* * 9,924.6 kg / 0.2519 = 39,398.9 kg - stage weight

* *30,398.9 kg * 0.0700 = *2,757.9 kg - structure weight

* *30,398.9 kg * 0.6781 = 26,716.4 kg - propellant weight



* *30,398.9 kg / 0.2519 = 156,406.8 kg - take off weight

* 156,406.8 kg * 0.0700 = *10,948.5 kg - structure weight

* 156,406.8 kg * 0.6781 = 106,059.4 kg - propellant weight



Converting 3 Stages to 7 Identical Flight Elements



Now if we take 2,500 away from 156,406.8 we obtain 153,906.8 kg. *If we then divide the total by 7 we obtain 21,986.6 kg. *Then we have



* *21,986.6 * 0.0700 = *1,539.0 kg - structure weight

* *21,986.6 * 0.9300 = 20,447.6 kg - propellant weight



Now consider 7 elements, each equipped with an aerospike engine, and cross feeding, along the lines describe here;



http://www.scribd.com/doc/45631474/S...rived-Launcher



Here is what the system is capable of;



*1,539.0 kg - Element Structure

20,447.6 kg - Element Propellant

21,986.6 kg - Element Total



*2,500.0 kg - Payload



156,406.2 kg Take off Weight

*68,459.8 kg Stage 2 Weight

*24,486.6 kg Stage 3 Weight



*81,790.4 kg Four Propellant Tanks

*40,895.2 kg Two Propellant Tanks

*20,447.6 kg One Propellant Tank



0.5229 First Stage Propellant Fraction

0.5974 Second Stage Propellant Fraction

0.8351 Third Stage Propellant Fraction



3.11 km/sec First Stage Speed

3.82 km/sec Second Stage Speed

7.57 km/sec Third Stage Speed



*3.11 km/sec First Stage Total Speed

*6.93 km/sec Second Stage Total Speed

14.50 km/sec Third Stage Total Speed



In fact, 2,725 kg of payload in combination with the third stage element can be projected from Earth with the requisite excess velocity.



Sending 7 Flight Elements to Venus



Now one interesting thing is that all the flight elements are the same shape, same weight, and same capabilities. *They are very much like the Space Shuttle External Tank, but instead of carrying 710 metric tons of propellant they are carrying only 20.5 metric tons of propellant and are thus only 30.7% the size of the External Tank. *That is a tank 2.6 m in diameter and 14.4 m long.



So, imagine that seven third stage elements are projected to Venus all at the same time, with seven separate launches within the launch window.



So, we have seven flight elements on their way to Venus. *Six of which are carrying 2,725 kg of excess propellant and one of which is carrying a 2,500 kg payload and 225 kg of excess propellant.



Using the Venusian Atmosphere as Propellant Supply



They all arrive at Venus and execute an aerobraking manoeuvre high in the Venusian atmosphere.



Operating at 58 km.



In addition to inflatable wings these elements are equipped with balloons! *These deploy once the vehicle slows to subsonic speed high in the Venusian atmosphere. *The act like drogue chutes as they deploy. *They are then filled with hydrogen gas, evaporated from the propellant carried along on the voyage.



Venusian Atmosphere



The Venusian atmosphere has the following characteristics;



KM * * C * * * Pressure * Density

0 * * * 462 * * 92.10 * 65.592 kg/m3

5 * * * 424 * * 66.65 * 50.604 kg/m3

10 * * *385 * * 47.39 * 38.114 kg/m3

15 * * *348 * * 33.04 * 28.156 kg/m3

20 * * *306 * * 22.52 * 20.583 kg/m3

25 * * *264 * * 14.93 * 14.713 kg/m3

30 * * *222 * * 9.851 * 10.532 kg/m3

35 * * *180 * * 5.917 * *6.912 kg/m3

40 * * *143 * * 3.501 * *4.454 kg/m3

45 * * *110 * * 1.979 * *2.734 kg/m3

50 * * *75 * * *1.066 * *1.621 kg/m3

55 * * *27 * * *0.5314 * 0.937 kg/m3

60 * * *-10 * * 0.2357 * 0.474 kg/m3

65 * * *-30 * * 0.09765 *0.213 kg/m3

70 * * *-43 * * 0.03690 *0.085 kg/m3



Solar Power on Venus



Venus is closer to the Sun and rotates very slowly. *So, its easy to choose a landing site that's in constant sunlight, if one remains above the cloud layer on the planet.



The balloons are transparent and contain a 37 m diameter thin film reflector that focuses light. *The reflector focuses light on to a solar pumped laser which beams energy via an optical fibre to a high intensity photovoltaic power unit only 200 mm in diameter. *This tiny lightweight device produces 1.55 MW of electrical power which is used to process the Venusian atmosphere separating out the water vapour which occurs at 20 ppm concentration.



The water when obtained is then decomposed into hydrogen and oxygen and used to refill the empty propellant tanks with 2,921.1 kg of hydrogen and 17,526.5 kg of oxygen made from 26,289.8 kg of water vapour recovered from 1.32 million tonnes of Venusian atmosphere, releasing 5,842.2 kg of excess oxygen since the rockets run hydrogen rich. *Some of this oxygen is used for breathing.



Since the sun shines continuously high above the Venusian atmosphere during the term of the vehicle's stay on the planet, only 100,000 Watts of power is needed to break this water down to its component gases and liquefy them. *Another 300,000 watts is needed to process the 169 litres of Venusian atmosphere per second and extract the 292.1 litres per day of water vapour from it and break it down into its component gases.



With a capacity of 1.55 MW each system may produce up to 4x the amounts of propellant needed to refill the flight elements with propellant from the Venusian atmosphere in this way in less than 23 days after arrival. *Thereafter, extra propellant is provided to operate a fuel cell powered quad rotor designed to fly to the Venusian surface carrying the traveller in their high pressure refrigerated and highly insulated powered tungsten hard suit and return them to their 'nest' floating high above the Venusian surface..



The 37 m diameter balloon occupies 26,672 cubic meters when fully inflated. Immediately following arrival at Venus the system floats at an altitude of 65 km. *As each of the seven flight elements fill, they sink in the atmosphere to an altitude of 55 km.



All seven elements are equipped with thrusters. *They use these to navigate to remain near to one another. *After they are filled with propellant, they have the ability to navigate very near to one another, adjust their buoyancy to control altitude precisely. When within distance, they fire automated mooring lines at each other, pick them up with automated bollards and grips, and draw themselves together. *When together in this way they mechanically link to one another, and deploy cross-feed lines.



The system is now ready to retract their balloons and operate as a three stage launcher on Venus.



The seven elements then fire in a manner similar to that used to depart Earth, with only the piloted element leaving the Venusian system. *The other six flight elements re-enter the Venusian atmosphere, and deploy their balloons again to refill and repeat their operation. *In this way, follow on flights only need involve the launch of a single explorer since the other six element will already be on Venus provisioned and ready to go.



High Pressure Hard Shell Suit



The atmospheric diving suit has a long history and is capable of operating at 610 m depths on Earth. *This is a pressure of 61.5 atm. *The same pressure as 6km above the surface of Venus. *This technology when extended to 91.1 atm - about 900 meter depth for ocean diving - equals the pressures needed for Venus.



http://en.wikipedia.org/wiki/Atmospheric_diving_suit



In addition to pressure temperatures of 462 C must be withstood as well.. *This is achieved by incorporating layers of evacuated silicon carbide aerogels which have a very high resistance to heat transfer.



http://en.wikipedia.org/wiki/File:Ae...r_filtered.jpg



A 2.6 mm thick layer of aerogel of this type creates an inert coating over the tungsten layer and bonds easily with it and is quite stable at pressures and temperatures found on Venus' surface.



Similar systems of ceramic coated metals are used in high temperature piping by industry today in far harsher environments than found on Venus.



For a typical suit 945 watts must be removed from the system. *The refrigerator maintains 18-24 C internally and rejects up to 1,200 Watts to a radiator that operates at 800 C on the users backpack.



Sufficient propellant is brought down to Venusian surface to maintain life support for 48 hours of surface operations. *The Quadrotor takes 45 minutes to drop from altitude and two hours to climb back to altitude. *26 mm of aerogel are needed to insulate cryogenic gases, the rate of the use of these limits the stay times on the surface. *Waste water is kept and recycled on board the spacecraft once altitude is regained.



With intense sunlight available nearly all the time, sunlight may be converted to a spectrum of colors using solar pumped lasers to illuminate crops through optical fibres. *In this way, 6x the crops may be grown per unit of collector area than is grown on aeroponic systems today.



Quadrotors operating automatically on the Surface of Venus to extract materials which are then processed at the atomic scale with laser systems that vaporize rock, and use electrostatic fields to separate them by atomic weight, to then be recombined into any useful material and assembled using additive manufacturing - products can be made from the Venusian surface materials. *This includes aerial cities as well as compact aerial farms. *All of which operate in the CO2 atmosphere at an altitude of 58 km where the atmosphere is room temperature and 1 bar.



http://www.scribd.com/doc/121742582/Aerial-Farms



http://www.youtube.com/watch?v=MvRTALJp8DM



http://www.youtube.com/watch?v=geqip_0Vjec



http://www.youtube.com/watch?v=xvN9Ri1GmuY



Thus, during the interval between visits the six remaining booster elements may be equipped with hardware that allows the construction of significant infrastructure between flights - which is an interval of about 584 days for minimum energy trajectories.



http://www.youtube.com/watch?v=d7_3PDnihMg



http://www.youtube.com/watch?v=p9Jl3MJh0lI



http://www.dailymail.co.uk/sciencete...The-astonishin....

Here's some cool additively manufactured aluminum and titanium parts.

http://www.youtube.com/watch?v=zApmGFDA6ow

It gives you an idea of what can be done especially when integrated on the micro scale.

http://www.technologyreview.com/news...es-in-seconds/

You might recall that electron beam microscopes out perform optical microscopes. Reversing the direction of the beams its possible for electron beam driven epitaxy to make devices even smaller than the one shown above.

Self replicating machine cells that collect energy and materials found in the environment to extract what is needed to make copies of themselves, are around now.

Automation is around now that provides very advanced controls.

Within the next few months we will see a transformation of the way things are done on this planet.

Consider a single self-replicating machine cell that's solar powered and grabs air, water, sun and stone, to make copies of itself. At 2 grams per cc and 23 um diameter, 82.5 million cells are required for a kilogram. Since the cells themselves form arrays they assemble at a lower density of 1.481 g/cc so the 1 kg occupies 675.2 millilitres.

With a one hour replication time a single cell grows to 1 kg in 26 hours 18 minutes. A metric ton is available in 36 hours 16 minutes. A kilogram for every man woman and child on Earth in 59 hours and 1 minute. Ten metric tons for every man woman an child on Earth in 72 hours and 18 minutes.


http://www.scribd.com/doc/121742582/Aerial-Farms

http://www.scribd.com/doc/106112900/Resources

http://www.scribd.com/doc/77588930/Brand-New-World

http://www.scribd.com/doc/62745980/Flying-Home

http://www.scribd.com/doc/60934836/Vesta-2

Chemical rockets are adequate to send us to the planets with appropriate life support systems and suspended animation.

http://www.youtube.com/watch?v=uVAaZVz9pDs


On Saturday, June 8, 2013 9:46:22 PM UTC+12, wrote:
Good points. The suit is powered and equipped with sensors to drive the suit in a natural way. It has millions of degrees of freedom since it is produced by 3D printing technology. For these reasons its easy to wear. It is designed from the outset for long duration wear including things like an LED/optical fibre tanning capability among others.



http://www.youtube.com/watch?v=iNpbLRrdJxQ



http://www.youtube.com/watch?v=hf_rf6bGvhw



http://www.youtube.com/watch?v=BUUNt_N48EQ



http://www.youtube.com/watch?v=E7--ZWPVVdQ



On Saturday, June 8, 2013 3:19:19 AM UTC+12, Robert Clark wrote:

There is a lot of calculation there to review in a Usenet post.



Perhaps you should create a blog that collected your various



proposals.



The titanium spacesuit has the problem that it would be very



unwieldly to move around in even in zero-g for missions several months



long. And on a world such as Venus with gravity close to Earth it



would be virtually impossible even for short periods.



Here's another solution, just make the missions shorter. In the



debate about whether our next destination in space should be the Moon,



Mars, or an asteroid, a key factor that needs to be kept in mind is



that setting up a base first on the Moon would allow us to produce



virtually unlimited propellant to be placed orbit. This could make



interplanetary flights much shorter.



Try this calculation: say you used two or three shuttle ET sized



hydrolox stages and a habitation module say of size of Bigelow's



Sundancer, about 8.6 metric tons. How long would it take to make a



mission to Mars?







Bob Clark







On Jun 7, 10:23*am, wrote:



Yes, Venus with chemical rockets







With an escape velocity nearly equal to that of Earth, it was thought that manned flight to Venus that incorporated a landing on the planet would not be possible, since multi-stage flight would be required. *However, it is possible to send multi-stage elements to Venus and refuel them there using abundant solar power and materials extracted from the Venusian atmosphere.







Radiation Suit







I recently posted that a powered hardshell suit made of 2.6 cm of tungsten, massing 880 kg would provide more than adequate shielding for long-term interplanetary flight. *This suit when coated with ceramic insulator and equipped with appropriate refrigeration would be quite capable of operating on the Venusian surface.







Suspended Animation







I also pointed out that Dr. Mark Roth has developed a method of invoking suspended animation that is very efficient and had no upper limit. *The process is in human trials and being used every day to save lives in trauma units. *The biochemistry is very similar to what goes on in hibernation and appears to be capable of producing decades long stasis at low risk that is usable multiple times.







MEMS based systems highly reliable







I've said too that micro-electro-mechanical systems (MEMS) based equipment, which today is used in digital light projectors, accelerometers, inertial guidance systems, ink jet printers, plasma displays, and a host of other every day products, are readily adapted to producing rocket arrays capable of producing 340 kPascals of pressure very safely and reliably as well as use in highly redundant, very efficient and reliable life support processes and fuel cells, and other systems, achieving very high performance per unit weight.







Flight weight very low







As a result a very capable system massing only 2,500 kg may support a one man interplanetary scout ship using chemical hydrogen oxygen rockets.







Typical flight to Venus and Back







Consider the flight opportunity leaving Earth for Venus on 3/24/2017. *Hyperbolic excess velocity of 4.43 km/sec. *Arrival at Mars on 9/9/2017 with a hyperbolic excess velocity of 9.81 km/sec. *A stop over of 90 days and departure to Earth on 1/12/2018 with a hyperbolic excess velocity of 3.22 km/sec arriving back at earth on 5/4/2018 with a hyperbolic excess velocity of 2.86 km/sec.







Venus escape velocity is 10.36 km/sec



Earth escape velocity is 11.19 km/sec







That means that departing Earth the payload must have a speed of







* *sqrt(11.19^2+4.43^2) = 12.04 km/sec + 1.61 km/sec ascent loss = 13.65 km/sec







Arriving at Venus the payload arrives at the top of the Venusian atmosphere with a speed of







* sqrt(10.36^2 + 9.81^2) = 14.27 km/sec







Which is about 10 km/sec less than Galileo navigated through Jupiter's atmosphere a few decades ago.







Departing Venus the payload must have a speed of







*sqrt(10.36^2 + 3.22^2) = 10.85 km/sec







Arriving at Earth the payload arrives at the top of Earth's atmosphere with a speed of







* sqrt(11.19^2 + 2.85^2) = 11.55 km/sec







Chemical Rocket Requirements - 3 Stages







Now with a 4.2 km/sec exhaust speed for a hydrogen oxygen rocket and a 7% structural fraction, we can compute the following for a 2,500 kg payload and a 3 stage rocket;







* *14.27 / 3 = 4.76 km/sec per stage







* *u = 1 - 1/exp(4.76/4.20) = 0.6781 propellant fraction







* *1.0000 - 0.6781 - 0.0700 = 0.2519 payload fraction







* *2,500.0 kg / 0.2519 = 9,924.6 kg - stage weight



* *9,924.6 kg * 0.0700 = * 694.7 kg - structure weight



* *9,924.6 kg * 0.6781 = 6,729.9 kg - propellant weight







* * 9,924.6 kg / 0.2519 = 39,398.9 kg - stage weight



* *30,398.9 kg * 0.0700 = *2,757.9 kg - structure weight



* *30,398.9 kg * 0.6781 = 26,716.4 kg - propellant weight







* *30,398.9 kg / 0.2519 = 156,406.8 kg - take off weight



* 156,406.8 kg * 0.0700 = *10,948.5 kg - structure weight



* 156,406.8 kg * 0.6781 = 106,059.4 kg - propellant weight







Converting 3 Stages to 7 Identical Flight Elements







Now if we take 2,500 away from 156,406.8 we obtain 153,906.8 kg. *If we then divide the total by 7 we obtain 21,986.6 kg. *Then we have







* *21,986.6 * 0.0700 = *1,539.0 kg - structure weight



* *21,986.6 * 0.9300 = 20,447.6 kg - propellant weight







Now consider 7 elements, each equipped with an aerospike engine, and cross feeding, along the lines describe here;







http://www.scribd.com/doc/45631474/S...rived-Launcher







Here is what the system is capable of;







*1,539.0 kg - Element Structure



20,447.6 kg - Element Propellant



21,986.6 kg - Element Total







*2,500.0 kg - Payload







156,406.2 kg Take off Weight



*68,459.8 kg Stage 2 Weight



*24,486.6 kg Stage 3 Weight







*81,790.4 kg Four Propellant Tanks



*40,895.2 kg Two Propellant Tanks



*20,447.6 kg One Propellant Tank







0.5229 First Stage Propellant Fraction



0.5974 Second Stage Propellant Fraction



0.8351 Third Stage Propellant Fraction







3.11 km/sec First Stage Speed



3.82 km/sec Second Stage Speed



7.57 km/sec Third Stage Speed







*3.11 km/sec First Stage Total Speed



*6.93 km/sec Second Stage Total Speed



14.50 km/sec Third Stage Total Speed







In fact, 2,725 kg of payload in combination with the third stage element can be projected from Earth with the requisite excess velocity.







Sending 7 Flight Elements to Venus







Now one interesting thing is that all the flight elements are the same shape, same weight, and same capabilities. *They are very much like the Space Shuttle External Tank, but instead of carrying 710 metric tons of propellant they are carrying only 20.5 metric tons of propellant and are thus only 30.7% the size of the External Tank. *That is a tank 2.6 m in diameter and 14.4 m long.







So, imagine that seven third stage elements are projected to Venus all at the same time, with seven separate launches within the launch window.







So, we have seven flight elements on their way to Venus. *Six of which are carrying 2,725 kg of excess propellant and one of which is carrying a 2,500 kg payload and 225 kg of excess propellant.







Using the Venusian Atmosphere as Propellant Supply







They all arrive at Venus and execute an aerobraking manoeuvre high in the Venusian atmosphere.







Operating at 58 km.







In addition to inflatable wings these elements are equipped with balloons! *These deploy once the vehicle slows to subsonic speed high in the Venusian atmosphere. *The act like drogue chutes as they deploy. *They are then filled with hydrogen gas, evaporated from the propellant carried along on the voyage.







Venusian Atmosphere







The Venusian atmosphere has the following characteristics;







KM * * C * * * Pressure * Density



0 * * * 462 * * 92.10 * 65.592 kg/m3



5 * * * 424 * * 66.65 * 50.604 kg/m3



10 * * *385 * * 47.39 * 38.114 kg/m3



15 * * *348 * * 33.04 * 28.156 kg/m3



20 * * *306 * * 22.52 * 20.583 kg/m3



25 * * *264 * * 14.93 * 14.713 kg/m3



30 * * *222 * * 9.851 * 10.532 kg/m3



35 * * *180 * * 5.917 * *6.912 kg/m3



40 * * *143 * * 3.501 * *4.454 kg/m3



45 * * *110 * * 1.979 * *2.734 kg/m3



50 * * *75 * * *1.066 * *1.621 kg/m3



55 * * *27 * * *0.5314 * 0.937 kg/m3



60 * * *-10 * * 0.2357 * 0.474 kg/m3



65 * * *-30 * * 0.09765 *0.213 kg/m3



70 * * *-43 * * 0.03690 *0.085 kg/m3







Solar Power on Venus







Venus is closer to the Sun and rotates very slowly. *So, its easy to choose a landing site that's in constant sunlight, if one remains above the cloud layer on the planet.







The balloons are transparent and contain a 37 m diameter thin film reflector that focuses light. *The reflector focuses light on to a solar pumped laser which beams energy via an optical fibre to a high intensity photovoltaic power unit only 200 mm in diameter. *This tiny lightweight device produces 1.55 MW of electrical power which is used to process the Venusian atmosphere separating out the water vapour which occurs at 20 ppm concentration.







The water when obtained is then decomposed into hydrogen and oxygen and used to refill the empty propellant tanks with 2,921.1 kg of hydrogen and 17,526.5 kg of oxygen made from 26,289.8 kg of water vapour recovered from 1.32 million tonnes of Venusian atmosphere, releasing 5,842.2 kg of excess oxygen since the rockets run hydrogen rich. *Some of this oxygen is used for breathing.







Since the sun shines continuously high above the Venusian atmosphere during the term of the vehicle's stay on the planet, only 100,000 Watts of power is needed to break this water down to its component gases and liquefy them. *Another 300,000 watts is needed to process the 169 litres of Venusian atmosphere per second and extract the 292.1 litres per day of water vapour from it and break it down into its component gases.







With a capacity of 1.55 MW each system may produce up to 4x the amounts of propellant needed to refill the flight elements with propellant from the Venusian atmosphere in this way in less than 23 days after arrival. *Thereafter, extra propellant is provided to operate a fuel cell powered quad rotor designed to fly to the Venusian surface carrying the traveller in their high pressure refrigerated and highly insulated powered tungsten hard suit and return them to their 'nest' floating high above the Venusian surface.







The 37 m diameter balloon occupies 26,672 cubic meters when fully inflated. Immediately following arrival at Venus the system floats at an altitude of 65 km. *As each of the seven flight elements fill, they sink in the atmosphere to an altitude of 55 km.







All seven elements are equipped with thrusters. *They use these to navigate to remain near to one another. *After they are filled with propellant, they have the ability to navigate very near to one another, adjust their buoyancy to control altitude precisely. When within distance, they fire automated mooring lines at each other, pick them up with automated bollards and grips, and draw themselves together. *When together in this way they mechanically link to one another, and deploy cross-feed lines.







The system is now ready to retract their balloons and operate as a three stage launcher on Venus.







The seven elements then fire in a manner similar to that used to depart Earth, with only the piloted element leaving the Venusian system. *The other six flight elements re-enter the Venusian atmosphere, and deploy their balloons again to refill and repeat their operation. *In this way, follow on flights only need involve the launch of a single explorer since the other six element will already be on Venus provisioned and ready to go.







High Pressure Hard Shell Suit







The atmospheric diving suit has a long history and is capable of operating at 610 m depths on Earth. *This is a pressure of 61.5 atm. *The same pressure as 6km above the surface of Venus. *This technology when extended to 91.1 atm - about 900 meter depth for ocean diving - equals the pressures needed for Venus.







http://en.wikipedia.org/wiki/Atmospheric_diving_suit







In addition to pressure temperatures of 462 C must be withstood as well. *This is achieved by incorporating layers of evacuated silicon carbide aerogels which have a very high resistance to heat transfer.







http://en.wikipedia.org/wiki/File:Ae...r_filtered.jpg







A 2.6 mm thick layer of aerogel of this type creates an inert coating over the tungsten layer and bonds easily with it and is quite stable at pressures and temperatures found on Venus' surface.







Similar systems of ceramic coated metals are used in high temperature piping by industry today in far harsher environments than found on Venus.







For a typical suit 945 watts must be removed from the system. *The refrigerator maintains 18-24 C internally and rejects up to 1,200 Watts to a radiator that operates at 800 C on the users backpack.







Sufficient propellant is brought down to Venusian surface to maintain life support for 48 hours of surface operations. *The Quadrotor takes 45 minutes to drop from altitude and two hours to climb back to altitude. *26 mm of aerogel are needed to insulate cryogenic gases, the rate of the use of these limits the stay times on the surface. *Waste water is kept and recycled on board the spacecraft once altitude is regained.







With intense sunlight available nearly all the time, sunlight may be converted to a spectrum of colors using solar pumped lasers to illuminate crops through optical fibres. *In this way, 6x the crops may be grown per unit of collector area than is grown on aeroponic systems today.







Quadrotors operating automatically on the Surface of Venus to extract materials which are then processed at the atomic scale with laser systems that vaporize rock, and use electrostatic fields to separate them by atomic weight, to then be recombined into any useful material and assembled using additive manufacturing - products can be made from the Venusian surface materials. *This includes aerial cities as well as compact aerial farms. *All of which operate in the CO2 atmosphere at an altitude of 58 km where the atmosphere is room temperature and 1 bar.







http://www.scribd.com/doc/121742582/Aerial-Farms







http://www.youtube.com/watch?v=MvRTALJp8DM







http://www.youtube.com/watch?v=geqip_0Vjec







http://www.youtube.com/watch?v=xvN9Ri1GmuY







Thus, during the interval between visits the six remaining booster elements may be equipped with hardware that allows the construction of significant infrastructure between flights - which is an interval of about 584 days for minimum energy trajectories.







http://www.youtube.com/watch?v=d7_3PDnihMg







http://www.youtube.com/watch?v=p9Jl3MJh0lI







http://www.dailymail.co.uk/sciencete...The-astonishin....

On Jun 8, 6:19*am, wrote:
...

Chemical rockets are adequate to send us to the planets with appropriate life support systems and suspended animation.

http://www.youtube.com/watch?v=uVAaZVz9pDs

Thanks for that. We could use suspended animation for small, low cost
missions to Mars or to go to the far outer planets. However, by
hopscotching we could have much shorter flight times out at least to
Jupiter by setting up propellant depots along the way, first on the
Moon, then on Mars, then on some of the larger bodies in the asteroid
belt, such as Ceres, Vesta, Pallas, etc., and finally, on the moons of
Jupiter for the return flights.
This hopscotching method might work all the way out to Saturn but
even with the very large propellant loads, say multiple shuttle ET
sized tanks, the flight time would still likely be several months. My
guess is though after setting up such base stations and propellant
depots all the way out to Jupiter, by that time we will have more
efficient propulsion such as fission or solar thermal.

Bob Clark

On Sunday, June 9, 2013 3:02:43 AM UTC+12, Robert Clark wrote:
On Jun 8, 6:19*am, wrote:

...



Chemical rockets are adequate to send us to the planets with appropriate life support systems and suspended animation.



http://www.youtube.com/watch?v=uVAaZVz9pDs



Thanks for that. We could use suspended animation for small, low cost

missions to Mars or to go to the far outer planets. However, by

hopscotching we could have much shorter flight times out at least to

Jupiter by setting up propellant depots along the way, first on the

Moon, then on Mars, then on some of the larger bodies in the asteroid

belt, such as Ceres, Vesta, Pallas, etc., and finally, on the moons of

Jupiter for the return flights.

This hopscotching method might work all the way out to Saturn but

even with the very large propellant loads, say multiple shuttle ET

sized tanks, the flight time would still likely be several months. My

guess is though after setting up such base stations and propellant

depots all the way out to Jupiter, by that time we will have more

efficient propulsion such as fission or solar thermal.



Bob Clark

Minimum energy transfer orbits, Hohmann transfer orbits, give us access to the solar system with less than 16.5 km/sec delta vee. Atmospheres allow aerobraking, which makes Mars and Venus of particular interest. Jupiter and the outer planets are interesting as well as Titan.

The same process of using balloons to allow flight elements to float in the skies of Venus are adapted to float in the skies of the gas giants, or the atmosphere of Titan, while sunlight is harvested to refuel the vehicle. The vehicle then explores the local system and eventually returns to Mars or Earth.

The presence of freely available water in the Snows of Mars,

http://www.nasa.gov/mission_pages/ph...-20080929.html

combined with high levels of solar power relative to the outer solar system, gives us the ability to set up a fuel depot on Mars with automated equipment

http://www.youtube.com/watch?v=i3ernrkZ91E

http://www.youtube.com/watch?v=JnkMyfQ5YfY

http://www.youtube.com/watch?v=nUQsRPJ1dYw

Explorers from Earth arrive at Mars, aerobrake, and refuel.

Folks like Robert Zubrin have shown this can be used to return the vehicle to Earth easily. However, there is no requirement to return the vehicle to Earth. Refueled vehicles are also used to depart Mars and fly anywhere in the solar system with a single chemical stage.

You are correct that specially built stages designed to make use of the atmospheres of Jupiter, Saturn, Titan, Uranus and Neptune, as a chemical feedstock, and use available sunlight to process that atmosphere into hydrogen and oxygen fuel, will be used to support ongoing operations.

Using aerobraking at our destination and then launching to explore the moons of each of the outer planets, and then return to Mars or the Earth, is all possible using this approach.

Due the lack of atmosphere, Mercury, and Pluto are the only bodies that require laser propulsion advances to be considered for human exploration with chemical fuels. The moon is possible only because of the low surface gravity and proximity to Earth. Diemos and Phobos, along with the asteroid belt, is also reachable from Mars for the same reason.

Advanced laser propulsion isn't really an issue since laser power beaming to solve Earth's energy problems will make its appearance as soon as our cultural decline is reversed. The application of this 30 year old technology to propulsion will revolutionize interplanetary commerce resulting in the industrial development of off-world resources to meet human need. This will transform our economy and life styles and open the skies to humanity. The further application of laser light sails and solar pumped lasers will take us to the nearby stars in large numbers.

However, today, without all of that, we have the capacity to go to Venus with chemical rockets and return along the lines discussed.

A motorized suit, using pizeoelectric motor that is lightweight quite compact has high torque operates at low speed.

How to model it.
http://www.youtube.com/watch?v=WrQWcadyM7Q

Example motor
http://www.youtube.com/watch?v=SpYbMuCF-6k

Application in powered suit
http://www.youtube.com/watch?v=ynL8BCXih8U

Medical Application
http://www.youtube.com/watch?v=rnKkQmfaTv4

Radiation Application
http://www.telegraph.co.uk/technolog...nstration.html

Obviously - Fukishima radiation protection is very similar to what we're discussing here.

Advanced locomotion controls make this sort of system much more flexible and natural and easier to use
http://www.youtube.com/watch?v=nUQsRPJ1dYw

The suit, made of 3D printed tungsten, titanium and plastics, of thousands of articulating parts with thousands of powered joints automatically adjusts to the wearer's body.

3D Printed fashion
http://www.youtube.com/watch?v=BUUNt_N48EQ
http://www.youtube.com/watch?v=_vHrrBtSMvk