http://nextbigfuture.com/
September 11, 2015
The impossible task of traveling 25.6 trillion miles to Alpha Centauri, our closest star,
is now possible. Using a Directed Energy System for Targeting of
Asteroids and exploRation (DE-STAR), a versatile, scalable phased-array
laser system, it can be reached in a short 16 years. Our project entails
carrying out both computational and experimental studies of specific
uses of DE-STAR to investigate photon recycling and spacecraft
propulsion. Photon recycling is a unique term used to describe a form of
energy conservation relative to this project. This effect will greatly
improve the efficiency of spacecraft making interstellar flight more
plausible. What lies beyond our solar system is one of the biggest
mysteries of mankind and it finally has the potential to be solved.
The DESTAR interstellar laser propulsion system is modular, scalable and on a very rapid development path. It lends itself to a roadmap.
There has been a game change in directed energy technology whose consequences are profound for many applications including photon driven propulsion. This allows for a completely modular and scalable technology without "dead ends".
Laser efficiencies are near 50%. The rise in efficiency will not be one of the enabling elements along the road map but free space phase control over large distances during the acceleration phase will be. This will require understanding the optics, phase noise and systematic effects of our combined on-board metrology and off-board phase servo feedback.
Reflector stability during acceleration will also be on the critical path as will increasing the TRL of the amplifiers for space use. For convenience we break the roadmap into several steps. One of the critical development items for space deployment is greatly lowering the mass of the radiators. While this sounds like a decidedly low tech item to work on, it turns out to be one of the critical mass drivers for space deployment. Current radiators have a mass to radiated power of 25 kg/kw, for radiated temperatures near 300K. This is an area where some new ideas are needed. With our current Yb fiber baseline laser amplifier mass to power of 5kg/kw (with a likely 5 year roadmap to 1 kg/kw) and current space photovoltaics of less than 7 kg/kw, the radiators are a serious issue for large scale space deployment.
The same basic system can be used for many purposes including both stand-on and stand-off planetary defense from virtually all threats with rapid response, orbital debris mitigation, orbital boosting from LEO to GEO for example, future ground to LEO laser assisted launchers, standoff composition analysis of distant object through molecular line absorption, active illumination of asteroids and other solar system bodies, beamed power to distant spacecraft among others. The same system can also be used for beaming power down to the Earth via micro or mm waves for selected applications. This technology will give us transformative options that are not possible now and allows us to go far beyond our existing chemical propulsion systems.
Consider a 1 gram payload attached to a 0.7 meter diameter sail. Image Adrian Mann
Fiber solid state lasers (SSLs) are widely used in industry—tens of thousands are used by auto and truck manufacturing firms for cutting and welding metal. They are considered to be a very robust technology. One fiber SSL prototype demonstrator developed by the Navy, called the Laser Weapon System(LaWS), had a beam power of 33 kW.
Operational Maturation and Steps:
Step 1 - Ground based - Small phased array, beam targeting and stability tests - 10 kw
Step II – Ground based - Target levitation and lab scale beam line acceleration tests - 10 kw
Step III – Ground based - Beam formation at large array spacing –
Step IV – Ground based - Scale to 100 kW with arrays sizes in the 1-3 m size –
Step V – Ground based - Scale to 1 MW with 10 m optics –
Step VI – Orbital testing with small 1-3 class arrays and 10-100kw power – ISS possibility
Step VII – Orbital array assembly tests in 10 m class array
Step VIII – Orbital assembly with sparse array at 100 m level –
Step IX – Orbital filled 100 m array
Step X – Orbital sparse 1km array
Step XI – Orbital filled 1 km array
Step XII – Orbital sparse 10 km array
Step XIII – Orbital filled 10 km array
The more modest size systems can be completely tested on the ground as well as sub-orbital flight tested on balloons or possibly sounding rocket. While the largest sized systems (km scale) are required for interstellar missions, small systems have immediate use for roadmap development and applications such as sending small probes into the solar system and then working our way outward as larger laser arrays are built. The laser array is modular, leading to mass production, so that a larger array can be built by adding elements to a smaller array. Array testing and propulsion tests are feasible at all levels allowing for roadmap development rather than "all or nothing". Small array can also be used for orbital debris removal, ISS defense from space debris as well as stand-on systems for planetary defense so again there is a use at practically every level and funding is well amortized over multiple uses. This allows practical justification for construction. In addition there is an enormous leveraging of DoD and DARPA funds for Directed Energy systems that dramatically lowers the NASA costs.
Phase lockable lasers and current PV performance - New fiber-fed lasers at 1 μm have efficiencies near 40% (DARPA Excalibur program currently at 5 kg/kW with near term goal of 1 kg/kW). They assume incremental efficiency increases to 70% though current efficiencies are already good enough to start the program. It is conceivable that power density could increase to 10 kW/kg in 10-20 years given the current pace. Current space multi-junction PV has an efficiency of nearing 40% with deployable mass per power of less than 7 kg/kW (ATK Megaflex as baselined for DE-STARLITE). Multi junction devices with efficiency in excess of 50% are on the horizon with current laboratory work exploring PV at efficiencies up to 70% over the next decade. We anticipate over a 20 year period PV efficiency will rise significantly, though it is NOT necessary for the roadmap to proceed. The roadmap is relatively "fault tolerant" in technology develop. Array level metrology as a part of the multi level servo feedback system is a critical element and one where recent advances in low cost nanometer level metrology for space applications is another key technology. One surprising area that needs significant work is the simple radiators that radiate excess heat. Currently this is the largest mass sub system at 25 kg/kw (radiated). The increase in laser efficiency reduces the radiator mass as does the possibility to run the lasers well above 300K. Radiation hardening/ resistance and the TRL levels needed for orbital use are another area they are currently exploring.
Wafer Scale Spacecraft. Recent work at UCSB on Si photonics now allows us to design and build a "spacecraft on a wafer". The recent (UCSB) work in phased array lasers on a wafer for ground-based optical communications combined with the ability to combine optical arrays (CMOS imagers for example) and MEMS accelerometers and gyros as well as many other sensors and computational abilities allows for extremely complex and novel systems. Traditional spacecraft are still largely built so that the mass is dominated by the packaging and interconnects rather than the fundamental limits on sensors. Our approach is similar to comparing a laptop of today to a super computer with similar power of 20 years ago and even a laptop is dominated by the human interface (screen and keyboard) rather than the processor and memory. Combining nano photonics, MEMS and electronics with recent UCSB work on Si nano wire thermal converters allows us to design a wafer that also has an embedded RTG or beta converter power source (recent LMCO work on thin film beta converters as an example) that can power the system over the many decades required in space. Combined with small photon thrusters (embedded LEDs/lasers for nN thrust steering on the wafer gives a functional spacecraft
Adding a second reflector we get double or triple amount of force than on just one reflector.
Technology Maturation:
Laser and Phased Array
* Increase TRL of laser amplifiers to at least TRL 6
* Test of low mass thin film optics as an option
* Reduce SBS effect to lower bandwidth and increase coherence time/ length
* Optimize multiple lower power amplifiers vs fewer higher power units – SBS/coherence trades
* Maturation and miniaturization of phase control elements for phased array
* Phase tapping and feedback on structure
* Structural metrology designs
* Study of optimized Kalman filters as part of phase control and servo targeting loop
* Study and test near field phase feedback from small free-flyer elements
* Study beam profiling and methods to smooth beam on reflector
* Beam randomization techniques to flatten beam
Reflector
* Study multilayer dielectric coating to minimize loss and maximize reflectivity – trade study
* Study materials designs for minimal mass reflectors – plastics vs glasses
* Shape designs for reflector stability - shaping
* Study designs with varying thicknesses and dielectric layers
* Study designs with low laser line absorption and high thermal IR absorption (emission)
* Study broader band reflectors to deal with relativistic wavelength shift with speed
* Study self stabilizing designs
* Simulations of reflector stability and oscillations during acceleration phase – shape changes
* Study spinning reflector to aid stability and randomization of differential force and heating
* Study techniques for reflector to laser active feedback
* Study techniques to keep beam on reflector
Wafer scale spacecraft
* Study materials for lowest power and high radiation resistance and compatibility with sensors
* Determine power requirements
* Study onboard power options – RTG, beta converter, beamed power
* Design narrow bandgap PV for beamed power phase
* Design on-wafer laser communications
* Design optical and IR imaging sensors
* Star tracker and laser lock modes
* Study swarm modes including intercommunications
* Design watchdog timers and redundant computational and sensor/ power topologies
* Test in beam line to simulate radiation exposure
* Design on-board or thin film “pop up” optics
* Design fiber optic or similar cloaking to mitigate heating during laser exposure
* Simulate thermal management both during laser exposure and during cruise phase
* Simulate radiation exposure during cruise phase
* Study materials for lowest power and high radiation resistance and compatibility with sensors
* Simulate imaging of target objects
* Study use of WaferSat for planetary and terrestrial probes
Communications
* Optimize wafer only laser communications
* Study feasibility of using acceleration reflector as part of laser communications
* Study feasibility of using reflector as thin film optics for laser comm and imaging
System Level
* Detailed design studies including mass tradeoffs and costing vs system size
* Develop cost roadmaps identifying critical elements as impediments to deployment vs size
* Design, build, test ground based structures with metrology feedback system
* Design and simulate orbital structures of various sizes (fixed vs sub element free flyer)
* Study orbital tradeoffs and project launcher feasibility vs time
* Study LEO, GEO, Lagrange points, lunar options
* Simulations of prober orbital trajectories including any Earth blockage effects
* Work with space PV designers to optimize efficiency and minimize mass
* Develop PV roadmap for mass, efficiency, rad resistance and aging
* Develop roadmap to reducing radiator mass by 10x as goal.
* Study target selection of possible exoplanet systems
* Study solar system targets
* Study multi mode use including space debris, beamed power, SPS, planetary defense …
* International space law issues
The following gives a selected set of possible missions. It is assumed that the reflector mass is equal to the base spacecraft mass (ie system mass not including reflector – or total system mass is twice the base spacecraft mass). The reflector is assumed to be 1 micron thick and the reflector density is assumed to be 1.4 g/cc. The laser array is assumed to be 10km on a side and the reflector is assumed to be square. The mass given is the base spacecraft mass and hence the reflector mass. The laser power is assumed to be 70 GW.
1g – wafer scale spacecraft with 0.85m reflector capable of significant relativistic light.
Time to when laser diffraction spot equals reflector size= 186s
Distance when laser diffraction spot equals reflector size=4.01 million km
Speed when laser diffraction spot equals reflector size=43100 km/s
Beta when laser diffraction spot equals reflector size=0.14
Speed with continued illumination=61,000 km/s
Beta with continued illumination=0.20
Acceleration when reflector is fully illuminated=2370 g
10g – multiple wafer scale systems with 2.7m reflector
Time to when laser diffraction spot equals reflector size= 1050s
Distance when laser diffraction spot equals reflector size=12.7 million km
Speed when laser diffraction spot equals reflector size=24300 km/s
Beta when laser diffraction spot equals reflector size=0.081
Speed with continued illumination=34300 km/s
Beta with continued illumination=0.11
Acceleration when reflector is fully illuminated=2.37x103g
100g – multiple wafer and sub class CubeSat systems with 8.5m reflector.
Time to when laser diffraction spot equals reflector size= 5880s
Distance when laser diffraction spot equals reflector size=40.1 million km
Speed when laser diffraction spot equals reflector size=13600 km/s
Beta when laser diffraction spot equals reflector size=0.046
Speed with continued illumination=19300 km/s
Beta with continued illumination=0.064
Acceleration when reflector is fully illuminated=237g
1kg – CubeSat class systems with 27m reflector.
Time to when laser diffraction spot equals reflector size= 33,200 seconds
Distance when laser diffraction spot equals reflector size=127 million km
Speed when laser diffraction spot equals reflector size=7670 km/s
Beta when laser diffraction spot equals reflector size=0.026
Speed with continued illumination=10800 km/s
Beta with continued illumination=0.036
Acceleration when reflector is fully illuminated=23.7g
10kg – significant imaging capability with 85m reflector.
Time to when laser diffraction spot equals reflector size= 186,000 seconds
Distance when laser diffraction spot equals reflector size=40 million km
Speed when laser diffraction spot equals reflector size=4310 km/s
Beta when laser diffraction spot equals reflector size=0.014
Speed with continued illumination=6100 km/s
Beta with continued illumination=0.020
Acceleration when reflector is fully illuminated=2.37g
100kg – significant robotic mission with multi mission capability with 270m reflector.
Time to when laser diffraction spot equals reflector size= 106,000 seconds
Distance when laser diffraction spot equals reflector size=1.27 billion km
Speed when laser diffraction spot equals reflector size=2430 km/s
Beta when laser diffraction spot equals reflector size=0.0081
Speed with continued illumination=3460 km/s
Beta with continued illumination=0.011
Acceleration when reflector is fully illuminated=0.237g
1000kg – smallest sized human “shuttle craft” system with 850m reflector.
Time to when laser diffraction spot equals reflector size= 5.88 million seconds
Distance when laser diffraction spot equals reflector size=4 billion km
Speed when laser diffraction spot equals reflector size=1360 km/s
Beta when laser diffraction spot equals reflector size=0.0046
Speed with continued illumination=1930 km/s
Beta with continued illumination=0.0064
Acceleration when reflector is fully illuminated=0.0237g
10,000kg – medium human capable or cargo craft for interplanetary travel with 2.7km reflector.
Time to when laser diffraction spot equals reflector size= 33.2 million seconds
Distance when laser diffraction spot equals reflector size=12.7 billion km
Speed when laser diffraction spot equals reflector size=767 km/s
Beta when laser diffraction spot equals reflector size=0.0026
Speed with continued illumination=1080 km/s
Beta with continued illumination=0.0036
Acceleration when reflector is fully illuminated=2.37x10^-3g
100,000kg – large human capable or cargo craft for interplanetary travel with 8.5km reflector.
Time to when laser diffraction spot equals reflector size= 186 million seconds
Distance when laser diffraction spot equals reflector size=40.1 billion km
Speed when laser diffraction spot equals reflector size=431 km/s
Beta when laser diffraction spot equals reflector size=0.0014
Speed with continued illumination=610 km/s
Beta with continued illumination=0.0020
Acceleration when reflector is fully illuminated=2.37x10^-4g
The DESTAR interstellar laser propulsion system is modular, scalable and on a very rapid development path. It lends itself to a roadmap.
There has been a game change in directed energy technology whose consequences are profound for many applications including photon driven propulsion. This allows for a completely modular and scalable technology without "dead ends".
Laser efficiencies are near 50%. The rise in efficiency will not be one of the enabling elements along the road map but free space phase control over large distances during the acceleration phase will be. This will require understanding the optics, phase noise and systematic effects of our combined on-board metrology and off-board phase servo feedback.
Reflector stability during acceleration will also be on the critical path as will increasing the TRL of the amplifiers for space use. For convenience we break the roadmap into several steps. One of the critical development items for space deployment is greatly lowering the mass of the radiators. While this sounds like a decidedly low tech item to work on, it turns out to be one of the critical mass drivers for space deployment. Current radiators have a mass to radiated power of 25 kg/kw, for radiated temperatures near 300K. This is an area where some new ideas are needed. With our current Yb fiber baseline laser amplifier mass to power of 5kg/kw (with a likely 5 year roadmap to 1 kg/kw) and current space photovoltaics of less than 7 kg/kw, the radiators are a serious issue for large scale space deployment.
The same basic system can be used for many purposes including both stand-on and stand-off planetary defense from virtually all threats with rapid response, orbital debris mitigation, orbital boosting from LEO to GEO for example, future ground to LEO laser assisted launchers, standoff composition analysis of distant object through molecular line absorption, active illumination of asteroids and other solar system bodies, beamed power to distant spacecraft among others. The same system can also be used for beaming power down to the Earth via micro or mm waves for selected applications. This technology will give us transformative options that are not possible now and allows us to go far beyond our existing chemical propulsion systems.
Fiber solid state lasers (SSLs) are widely used in industry—tens of thousands are used by auto and truck manufacturing firms for cutting and welding metal. They are considered to be a very robust technology. One fiber SSL prototype demonstrator developed by the Navy, called the Laser Weapon System(LaWS), had a beam power of 33 kW.
Operational Maturation and Steps:
Step 1 - Ground based - Small phased array, beam targeting and stability tests - 10 kw
Step II – Ground based - Target levitation and lab scale beam line acceleration tests - 10 kw
Step III – Ground based - Beam formation at large array spacing –
Step IV – Ground based - Scale to 100 kW with arrays sizes in the 1-3 m size –
Step V – Ground based - Scale to 1 MW with 10 m optics –
Step VI – Orbital testing with small 1-3 class arrays and 10-100kw power – ISS possibility
Step VII – Orbital array assembly tests in 10 m class array
Step VIII – Orbital assembly with sparse array at 100 m level –
Step IX – Orbital filled 100 m array
Step X – Orbital sparse 1km array
Step XI – Orbital filled 1 km array
Step XII – Orbital sparse 10 km array
Step XIII – Orbital filled 10 km array
The more modest size systems can be completely tested on the ground as well as sub-orbital flight tested on balloons or possibly sounding rocket. While the largest sized systems (km scale) are required for interstellar missions, small systems have immediate use for roadmap development and applications such as sending small probes into the solar system and then working our way outward as larger laser arrays are built. The laser array is modular, leading to mass production, so that a larger array can be built by adding elements to a smaller array. Array testing and propulsion tests are feasible at all levels allowing for roadmap development rather than "all or nothing". Small array can also be used for orbital debris removal, ISS defense from space debris as well as stand-on systems for planetary defense so again there is a use at practically every level and funding is well amortized over multiple uses. This allows practical justification for construction. In addition there is an enormous leveraging of DoD and DARPA funds for Directed Energy systems that dramatically lowers the NASA costs.
Phase lockable lasers and current PV performance - New fiber-fed lasers at 1 μm have efficiencies near 40% (DARPA Excalibur program currently at 5 kg/kW with near term goal of 1 kg/kW). They assume incremental efficiency increases to 70% though current efficiencies are already good enough to start the program. It is conceivable that power density could increase to 10 kW/kg in 10-20 years given the current pace. Current space multi-junction PV has an efficiency of nearing 40% with deployable mass per power of less than 7 kg/kW (ATK Megaflex as baselined for DE-STARLITE). Multi junction devices with efficiency in excess of 50% are on the horizon with current laboratory work exploring PV at efficiencies up to 70% over the next decade. We anticipate over a 20 year period PV efficiency will rise significantly, though it is NOT necessary for the roadmap to proceed. The roadmap is relatively "fault tolerant" in technology develop. Array level metrology as a part of the multi level servo feedback system is a critical element and one where recent advances in low cost nanometer level metrology for space applications is another key technology. One surprising area that needs significant work is the simple radiators that radiate excess heat. Currently this is the largest mass sub system at 25 kg/kw (radiated). The increase in laser efficiency reduces the radiator mass as does the possibility to run the lasers well above 300K. Radiation hardening/ resistance and the TRL levels needed for orbital use are another area they are currently exploring.
Wafer Scale Spacecraft. Recent work at UCSB on Si photonics now allows us to design and build a "spacecraft on a wafer". The recent (UCSB) work in phased array lasers on a wafer for ground-based optical communications combined with the ability to combine optical arrays (CMOS imagers for example) and MEMS accelerometers and gyros as well as many other sensors and computational abilities allows for extremely complex and novel systems. Traditional spacecraft are still largely built so that the mass is dominated by the packaging and interconnects rather than the fundamental limits on sensors. Our approach is similar to comparing a laptop of today to a super computer with similar power of 20 years ago and even a laptop is dominated by the human interface (screen and keyboard) rather than the processor and memory. Combining nano photonics, MEMS and electronics with recent UCSB work on Si nano wire thermal converters allows us to design a wafer that also has an embedded RTG or beta converter power source (recent LMCO work on thin film beta converters as an example) that can power the system over the many decades required in space. Combined with small photon thrusters (embedded LEDs/lasers for nN thrust steering on the wafer gives a functional spacecraft
Adding a second reflector we get double or triple amount of force than on just one reflector.
Technology Maturation:
Laser and Phased Array
* Increase TRL of laser amplifiers to at least TRL 6
* Test of low mass thin film optics as an option
* Reduce SBS effect to lower bandwidth and increase coherence time/ length
* Optimize multiple lower power amplifiers vs fewer higher power units – SBS/coherence trades
* Maturation and miniaturization of phase control elements for phased array
* Phase tapping and feedback on structure
* Structural metrology designs
* Study of optimized Kalman filters as part of phase control and servo targeting loop
* Study and test near field phase feedback from small free-flyer elements
* Study beam profiling and methods to smooth beam on reflector
* Beam randomization techniques to flatten beam
Reflector
* Study multilayer dielectric coating to minimize loss and maximize reflectivity – trade study
* Study materials designs for minimal mass reflectors – plastics vs glasses
* Shape designs for reflector stability - shaping
* Study designs with varying thicknesses and dielectric layers
* Study designs with low laser line absorption and high thermal IR absorption (emission)
* Study broader band reflectors to deal with relativistic wavelength shift with speed
* Study self stabilizing designs
* Simulations of reflector stability and oscillations during acceleration phase – shape changes
* Study spinning reflector to aid stability and randomization of differential force and heating
* Study techniques for reflector to laser active feedback
* Study techniques to keep beam on reflector
Wafer scale spacecraft
* Study materials for lowest power and high radiation resistance and compatibility with sensors
* Determine power requirements
* Study onboard power options – RTG, beta converter, beamed power
* Design narrow bandgap PV for beamed power phase
* Design on-wafer laser communications
* Design optical and IR imaging sensors
* Star tracker and laser lock modes
* Study swarm modes including intercommunications
* Design watchdog timers and redundant computational and sensor/ power topologies
* Test in beam line to simulate radiation exposure
* Design on-board or thin film “pop up” optics
* Design fiber optic or similar cloaking to mitigate heating during laser exposure
* Simulate thermal management both during laser exposure and during cruise phase
* Simulate radiation exposure during cruise phase
* Study materials for lowest power and high radiation resistance and compatibility with sensors
* Simulate imaging of target objects
* Study use of WaferSat for planetary and terrestrial probes
Communications
* Optimize wafer only laser communications
* Study feasibility of using acceleration reflector as part of laser communications
* Study feasibility of using reflector as thin film optics for laser comm and imaging
System Level
* Detailed design studies including mass tradeoffs and costing vs system size
* Develop cost roadmaps identifying critical elements as impediments to deployment vs size
* Design, build, test ground based structures with metrology feedback system
* Design and simulate orbital structures of various sizes (fixed vs sub element free flyer)
* Study orbital tradeoffs and project launcher feasibility vs time
* Study LEO, GEO, Lagrange points, lunar options
* Simulations of prober orbital trajectories including any Earth blockage effects
* Work with space PV designers to optimize efficiency and minimize mass
* Develop PV roadmap for mass, efficiency, rad resistance and aging
* Develop roadmap to reducing radiator mass by 10x as goal.
* Study target selection of possible exoplanet systems
* Study solar system targets
* Study multi mode use including space debris, beamed power, SPS, planetary defense …
* International space law issues
The following gives a selected set of possible missions. It is assumed that the reflector mass is equal to the base spacecraft mass (ie system mass not including reflector – or total system mass is twice the base spacecraft mass). The reflector is assumed to be 1 micron thick and the reflector density is assumed to be 1.4 g/cc. The laser array is assumed to be 10km on a side and the reflector is assumed to be square. The mass given is the base spacecraft mass and hence the reflector mass. The laser power is assumed to be 70 GW.
1g – wafer scale spacecraft with 0.85m reflector capable of significant relativistic light.
Time to when laser diffraction spot equals reflector size= 186s
Distance when laser diffraction spot equals reflector size=4.01 million km
Speed when laser diffraction spot equals reflector size=43100 km/s
Beta when laser diffraction spot equals reflector size=0.14
Speed with continued illumination=61,000 km/s
Beta with continued illumination=0.20
Acceleration when reflector is fully illuminated=2370 g
10g – multiple wafer scale systems with 2.7m reflector
Time to when laser diffraction spot equals reflector size= 1050s
Distance when laser diffraction spot equals reflector size=12.7 million km
Speed when laser diffraction spot equals reflector size=24300 km/s
Beta when laser diffraction spot equals reflector size=0.081
Speed with continued illumination=34300 km/s
Beta with continued illumination=0.11
Acceleration when reflector is fully illuminated=2.37x103g
100g – multiple wafer and sub class CubeSat systems with 8.5m reflector.
Time to when laser diffraction spot equals reflector size= 5880s
Distance when laser diffraction spot equals reflector size=40.1 million km
Speed when laser diffraction spot equals reflector size=13600 km/s
Beta when laser diffraction spot equals reflector size=0.046
Speed with continued illumination=19300 km/s
Beta with continued illumination=0.064
Acceleration when reflector is fully illuminated=237g
1kg – CubeSat class systems with 27m reflector.
Time to when laser diffraction spot equals reflector size= 33,200 seconds
Distance when laser diffraction spot equals reflector size=127 million km
Speed when laser diffraction spot equals reflector size=7670 km/s
Beta when laser diffraction spot equals reflector size=0.026
Speed with continued illumination=10800 km/s
Beta with continued illumination=0.036
Acceleration when reflector is fully illuminated=23.7g
10kg – significant imaging capability with 85m reflector.
Time to when laser diffraction spot equals reflector size= 186,000 seconds
Distance when laser diffraction spot equals reflector size=40 million km
Speed when laser diffraction spot equals reflector size=4310 km/s
Beta when laser diffraction spot equals reflector size=0.014
Speed with continued illumination=6100 km/s
Beta with continued illumination=0.020
Acceleration when reflector is fully illuminated=2.37g
100kg – significant robotic mission with multi mission capability with 270m reflector.
Time to when laser diffraction spot equals reflector size= 106,000 seconds
Distance when laser diffraction spot equals reflector size=1.27 billion km
Speed when laser diffraction spot equals reflector size=2430 km/s
Beta when laser diffraction spot equals reflector size=0.0081
Speed with continued illumination=3460 km/s
Beta with continued illumination=0.011
Acceleration when reflector is fully illuminated=0.237g
1000kg – smallest sized human “shuttle craft” system with 850m reflector.
Time to when laser diffraction spot equals reflector size= 5.88 million seconds
Distance when laser diffraction spot equals reflector size=4 billion km
Speed when laser diffraction spot equals reflector size=1360 km/s
Beta when laser diffraction spot equals reflector size=0.0046
Speed with continued illumination=1930 km/s
Beta with continued illumination=0.0064
Acceleration when reflector is fully illuminated=0.0237g
10,000kg – medium human capable or cargo craft for interplanetary travel with 2.7km reflector.
Time to when laser diffraction spot equals reflector size= 33.2 million seconds
Distance when laser diffraction spot equals reflector size=12.7 billion km
Speed when laser diffraction spot equals reflector size=767 km/s
Beta when laser diffraction spot equals reflector size=0.0026
Speed with continued illumination=1080 km/s
Beta with continued illumination=0.0036
Acceleration when reflector is fully illuminated=2.37x10^-3g
100,000kg – large human capable or cargo craft for interplanetary travel with 8.5km reflector.
Time to when laser diffraction spot equals reflector size= 186 million seconds
Distance when laser diffraction spot equals reflector size=40.1 billion km
Speed when laser diffraction spot equals reflector size=431 km/s
Beta when laser diffraction spot equals reflector size=0.0014
Speed with continued illumination=610 km/s
Beta with continued illumination=0.0020
Acceleration when reflector is fully illuminated=2.37x10^-4g
A Small, Modular, Efficient Fusion Plant
Posted August 10, 2015
A
cutaway view of the proposed ARC reactor. Thanks to powerful new magnet
technology, the much smaller, less-expensive ARC reactor would deliver
the same power output as a much larger reactor. Illustration courtesy of
the MIT ARC team.
New design could finally help to bring the long-sought power source closer to reality.
David L. Chandler | MIT News OfficeBut now, finally, the joke may no longer be true: Advances in magnet technology have enabled researchers at MIT to propose a new design for a practical compact tokamak fusion reactor — and it’s one that might be realized in as little as a decade, they say. The era of practical fusion power, which could offer a nearly inexhaustible energy resource, may be coming near.
Using these new commercially available superconductors, rare-earth barium copper oxide (REBCO) superconducting tapes, to produce high-magnetic field coils “just ripples through the whole design,” says Dennis Whyte, a professor of Nuclear Science and Engineering and director of MIT’s Plasma Science and Fusion Center. “It changes the whole thing.”
The stronger magnetic field makes it possible to produce the required magnetic confinement of the superhot plasma — that is, the working material of a fusion reaction — but in a much smaller device than those previously envisioned. The reduction in size, in turn, makes the whole system less expensive and faster to build, and also allows for some ingenious new features in the power plant design. The proposed reactor, using a tokamak (donut-shaped) geometry that is widely studied, is described in a paper in the journal Fusion Engineering and Design, co-authored by Whyte, PhD candidate Brandon Sorbom, and 11 others at MIT. The paper started as a design class taught by Whyte and became a student-led project after the class ended.
MIT
PhD candidate Brandon Sorbom holds REBCO superconducting tapes (left),
which are the enabling technology behind the ARC reactor. When it is
cooled to liquid nitrogen temperature, the superconducting tape can
carry as much current as the large copper conductor on the right,
enabling the construction of extremely high‑field magnets, which consume
minimal amounts of power. Photo: Jose‑Luis Olivares/MIT
The new reactor is designed for basic research on fusion and also as a potential prototype power plant that could produce significant power. The basic reactor concept and its associated elements are based on well-tested and proven principles developed over decades of research at MIT and around the world, the team says.
“The much higher magnetic field,” Sorbom says, “allows you to achieve much higher performance.”
Fusion, the nuclear reaction that powers the sun, involves fusing pairs of hydrogen atoms together to form helium, accompanied by enormous releases of energy. The hard part has been confining the superhot plasma — a form of electrically charged gas — while heating it to temperatures hotter than the cores of stars. This is where the magnetic fields are so important—they effectively trap the heat and particles in the hot center of the device.
While most characteristics of a system tend to vary in proportion to changes in dimensions, the effect of changes in the magnetic field on fusion reactions is much more extreme: The achievable fusion power increases according to the fourth power of the increase in the magnetic field. Thus, doubling the field would produce a 16-fold increase in the fusion power. “Any increase in the magnetic field gives you a huge win,” Sorbom says.
Tenfold boost in power
While the new superconductors do not produce quite a doubling of the field strength, they are strong enough to increase fusion power by about a factor of 10 compared to standard superconducting technology, Sorbom says. This dramatic improvement leads to a cascade of potential improvements in reactor design.
The world’s most powerful planned fusion reactor, a huge device called ITER that is under construction in France, is expected to cost around $40 billion. Sorbom and the MIT team estimate that the new design, about half the diameter of ITER (which was designed before the new superconductors became available), would produce about the same power at a fraction of the cost and in a shorter construction time.
But despite the difference in size and magnetic field strength, the proposed reactor, called ARC, is based on “exactly the same physics” as ITER, Whyte says. “We’re not extrapolating to some brand-new regime,” he adds.
Another key advance in the new design is a method for removing the the fusion power core from the donut-shaped reactor without having to dismantle the entire device. That makes it especially well-suited for research aimed at further improving the system by using different materials or designs to fine-tune the performance.
In addition, as with ITER, the new superconducting magnets would enable the reactor to operate in a sustained way, producing a steady power output, unlike today’s experimental reactors that can only operate for a few seconds at a time without overheating of copper coils.
Liquid protection
Another key advantage is that most of the solid blanket materials used to surround the fusion chamber in such reactors are replaced by a liquid material that can easily be circulated and replaced, eliminating the need for costly replacement procedures as the materials degrade over time.
“It’s an extremely harsh environment for [solid] materials,” Whyte says, so replacing those materials with a liquid could be a major advantage.
Right now, as designed, the reactor should be capable of producing about three times as much electricity as is needed to keep it running, but the design could probably be improved to increase that proportion to about five or six times, Sorbom says. So far, no fusion reactor has produced as much energy as it consumes, so this kind of net energy production would be a major breakthrough in fusion technology, the team says.
The design could produce a reactor that would provide electricity to about 100,000 people, they say. Devices of a similar complexity and size have been built within about five years, they say.
“Fusion energy is certain to be the most important source of electricity on earth in the 22nd century, but we need it much sooner than that to avoid catastrophic global warming,” says David Kingham, CEO of Tokamak Energy Ltd. in the UK, who was not connected with this research. “This paper shows a good way to make quicker progress,” he says.
The MIT research, Kingham says, “shows that going to higher magnetic fields, an MIT speciality, can lead to much smaller (and hence cheaper and quicker-to-build) devices.” The work is of “exceptional quality,” he says; “the next step … would be to refine the design and work out more of the engineering details, but already the work should be catching the attention of policy makers, philanthropists and private investors.”
The research was supported by the U.S. Department of Energy and the National Science Foundation.
http://nextbigfuture.com/
July 13, 2015
Boeing's fusion-fission hybrid propulsion patent is weak compared to the detailed NASA NIAC Pulsed Fission-Fusion design
Boeing has a patent for a laser fusion - fission hybrid jet propulsion system.
Boeing claims energy-efficient thrust can be produced by firing lasers at deuterium and tritium and then having the neutrons activate uranium 238 to generate more heat.
* Hot gases produced by the laser induced fusion are pushed out of a nozzle at the back of the engine, creating thrust.
* a neutrons hit a shell of uranium 238 which causes fission and generates lots of heat
* a heat exchanger uses the heat from the fission reaction to drive a turbine that generates the electricity that powers the lasers
They have different configurations
* one configuration generates ISP of about 2000 to 5000 seconds
* another configuration has an ISP of about 5000 to 25000 seconds
* another configuration an ISP of about 100,000 to 250,000.
I am not sure where there is enough innovation in the Boeing concepts for a patent. There have been several prior proposed fusion-fission hybrid propulsion systems.
I look at some other work and focus on the NIAC NASA Pulsed Fission-Fusion design. There is a lot more detailed modeling and work towards experimentation in the NASA Pulsed Fission-fusion design.
Boeing claims energy-efficient thrust can be produced by firing lasers at deuterium and tritium and then having the neutrons activate uranium 238 to generate more heat.
* Hot gases produced by the laser induced fusion are pushed out of a nozzle at the back of the engine, creating thrust.
* a neutrons hit a shell of uranium 238 which causes fission and generates lots of heat
* a heat exchanger uses the heat from the fission reaction to drive a turbine that generates the electricity that powers the lasers
They have different configurations
* one configuration generates ISP of about 2000 to 5000 seconds
* another configuration has an ISP of about 5000 to 25000 seconds
* another configuration an ISP of about 100,000 to 250,000.
I am not sure where there is enough innovation in the Boeing concepts for a patent. There have been several prior proposed fusion-fission hybrid propulsion systems.
I look at some other work and focus on the NIAC NASA Pulsed Fission-Fusion design. There is a lot more detailed modeling and work towards experimentation in the NASA Pulsed Fission-fusion design.
Other fusion-fission hybrid propulsion work and pure laser fusion work
Ted Kammash, Ricky Tang and Michael Hartman had a bi-modal fusion propulsion system in which Q-values of about unity or less are needed since the GDM will serve mainly as a neutron source. It is well known that fusion reactions are neutron rich but energy poor, while fission reactions are energy rich but neutron poor. We make use of this fact by considering a system in which the GDM device serves as a fast neutron source surrounded by a blanket of Th232 , which we utilize to breed U233 and simultaneously burn it to produce energy. For a reasonable size blanket and a D-T plasma density, size and temperature, we find that the proposed hybrid system is capable of producing tens of gigawatts of thermal power per centimeter. If we use this power to heat a hydrogen propellant, we find that a seven meter long engine can generate a specific impulse of about 59,000 seconds at a thrust of about 8 mega-newtons at a propellant flow rate of about 130 kg/sec. Such a propulsion capability would allow many meaningful space missions to be carried out in relatively short times. Furthermore, such a hybrid system can generate large amounts of electric power for surface power applications once destination is reached.
The use of fusion energy to propel vehicles in space has been investigated for several decades. Much of the earlier work focused on inertial fusion where laser beams are employed to ignite target pellets containing fusion fuel to produce the needed energy. With the realization that laser systems are massive and complicated, other drivers were examined to see if they can deliver the required energy to the target at much lower mass. Here, the use of antimatter was found to be especially effective. Modest amounts of antiprotons are found to be adequate to trigger fusion propulsion but the engineering challenges associated with this approach6 have to be addressed vigorously in order for it to be realizable. The major issue associated with the use of antimatter is availability since the current annual worldwide production rate stands at nanograms while most fusion propulsion schemes appear to require quantities on the order of several micrograms. With the world effort in achieving fusion power for terrestrial use focused on toroidal devices, such as tokamaks, very little attention was paid to magnetic fusion for propulsion applications. These devices do not appear to lend themselves geometrically for exhausting energetic plasma particles to generate thrust. Open-ended magnetic devices, on the other hand, are found to be especially suitable because they can confine a plasma long enough to be heated before being ejected from one of the mirror ends to produce thrust. Of particular advantage in this regard is the gasdynamic mirror (GDM) whose confinement properties are based on plasmas of such density and temperature as to make the ion-ion collision mean free path much shorter than the length. Under these conditions, the plasma behaves much like a fluid, and its escape from the system is analogous to the flow of a gas from a vessel with a hole. We focus on the GDM as the fusion component of the system we propose in this paper and demonstrate its usefulness for both space power and propulsion applications.
Kammash, Terry, Tang, Ricky and Hartman, Michael, "Fusion-Fission Hybrid Revisited – Potential for Space Applications", AIAA 2009.
Hyde, R. A., Wood, L., and Nuckolls, J., “Prospects for Rocket Propulsion with Laser-Induced Fusion Microexplosions,” 8th
Joint Propulsion Specialist Conference, New Orleans, LA, 1972, AIAA-1972-1063.
Martin, A. R., and Bond, A., “Project Daedalus,” Journal of the British Interplanetary Society, Supplement Volume, 1978.
Kammash, T., and Galbraith, D. L., “A Fusion Reactor for Space Applications,” Fusion Technology, Vol. 12, No. 11, 1987
NASA Rob Adams talks about fusion propulsion and hybrid pulsed fission fusion propulsion
NASA Scientist Dr Rob Adams speaks about Pulsed Fusion Propulsion, dense plasma focus fusion, z pinch fusion and the possibilities of high density compression of fusion fuels.
NAIC - Pulsed Fission-Fusion (PuFF) Propulsion System
Fission-ignited fusion systems have been operational – in weapon form – since the 1950’s. Leveraging insights gained from the weapons physics program, a Z-Pinch device could be used to ignite a thermonuclear deuterium trigger. The fusion neutrons will induce fission reaction in a surrounding uranium or thorium liner, releasing sufficient energy to further confine and heat the fusion plasma. The combined energy release from fission and fusion would then be directed using a magnetic nozzle to produce useful thrust. This type of concept could provide the efficiency of open cycle fusion propulsion devices with the relative small size and simplicity of fission systems; and would provide a radical improvement in our ability to explore destinations across the solar system and beyond. This proposal is modified version of last year’s proposal - addressing issues raised during that evaluation.
PUFF hybrid vehicle design and mission analysis showed concepts which could reach Mars in 37 days, and 1,000 astronomical unit (AU) interstellar precursor distances in 36 years
phase 1 proposal included modeling the above process first under steady state assumptions and second under a time variant integration. We proposed including these results into a Mars concept vehicle and finally proposing promising conditions to be evaluated experimentally in Phase II. In phase I we quickly realized that we needed to modify our approach. Our steady state work was completed as proposed, and the results indicated that one, a two stage compression system was not needed and two, that we wanted to move away from UF6. The steady state model shows much more margin than expected, to the point that we may well reach breakeven with the Charger – 1 facility, a 572 kJ Marx bank currently under refurbishment at UAH. Additionally we found that using gaseous D-T and UF6, provided a relatively simple prospect of using a pulsed injector, made reaching criticality more difficult. The introduction of large amounts of fluorine meant a radiative sink, sapping power from the fusion plasma and was harder to handle. Therefore we moved to a solid uranium target that held D-T under pressure. In so doing we could move our target closer to criticality and remove any material that did not sustain the reaction.
NASA Scientist Dr Rob Adams speaks about Pulsed Fusion Propulsion, dense plasma focus fusion, z pinch fusion and the possibilities of high density compression of fusion fuels.
NAIC - Pulsed Fission-Fusion (PuFF) Propulsion System
Fission-ignited fusion systems have been operational – in weapon form – since the 1950’s. Leveraging insights gained from the weapons physics program, a Z-Pinch device could be used to ignite a thermonuclear deuterium trigger. The fusion neutrons will induce fission reaction in a surrounding uranium or thorium liner, releasing sufficient energy to further confine and heat the fusion plasma. The combined energy release from fission and fusion would then be directed using a magnetic nozzle to produce useful thrust. This type of concept could provide the efficiency of open cycle fusion propulsion devices with the relative small size and simplicity of fission systems; and would provide a radical improvement in our ability to explore destinations across the solar system and beyond. This proposal is modified version of last year’s proposal - addressing issues raised during that evaluation.
PUFF hybrid vehicle design and mission analysis showed concepts which could reach Mars in 37 days, and 1,000 astronomical unit (AU) interstellar precursor distances in 36 years
phase 1 proposal included modeling the above process first under steady state assumptions and second under a time variant integration. We proposed including these results into a Mars concept vehicle and finally proposing promising conditions to be evaluated experimentally in Phase II. In phase I we quickly realized that we needed to modify our approach. Our steady state work was completed as proposed, and the results indicated that one, a two stage compression system was not needed and two, that we wanted to move away from UF6. The steady state model shows much more margin than expected, to the point that we may well reach breakeven with the Charger – 1 facility, a 572 kJ Marx bank currently under refurbishment at UAH. Additionally we found that using gaseous D-T and UF6, provided a relatively simple prospect of using a pulsed injector, made reaching criticality more difficult. The introduction of large amounts of fluorine meant a radiative sink, sapping power from the fusion plasma and was harder to handle. Therefore we moved to a solid uranium target that held D-T under pressure. In so doing we could move our target closer to criticality and remove any material that did not sustain the reaction.
However in moving to a solid target we complicated our time-variant model, now requiring us to develop phase change algorithms and stress-strain calculations for the solid matrix. We have continued efforts along this line but as expected we did not complete this model. After discussions with NIAC management we moved some of our resources to preparing existing equipment to support an experimental program testing various target configurations under a variety of z-pinches at different power levels. Contained in this report are our results preparing 200 J, 1kJ and 4-8 kJ pulsed power systems as well as a vacuum chamber and diagnostic equipment to evaluate generated plasmas.
We have also completed a point design of PuFF using the results of our steady state model. This design was then used to evaluate a couple missions of interest. At the behest of NIAC management we considered a more advanced version of the Mars mission, resulting in a vehicle that could reach Mars, one way, in 37 days with 25 mT of payload.
30-50% burnup in pulses
Long Range Plans
* NIAC Phase II
• Complete Charger 1 refurb
• Ignite PuFF plasma
• Continue magnetic nozzle research
* Charger II
• Construct breadboard PuFF system capable of 10‐20 Hz operation
- Upgrade to flightweight hardware – NASA
- Optimize pulse for maximum power output – DOE
- Astrodynamics, radiation protection, other research goals ‐ Various
SOURCES - US Patent, Youtube, NASA, NIAC, Rob Adams
Long Range Plans
* NIAC Phase II
• Complete Charger 1 refurb
• Ignite PuFF plasma
• Continue magnetic nozzle research
* Charger II
• Construct breadboard PuFF system capable of 10‐20 Hz operation
- Upgrade to flightweight hardware – NASA
- Optimize pulse for maximum power output – DOE
- Astrodynamics, radiation protection, other research goals ‐ Various
SOURCES - US Patent, Youtube, NASA, NIAC, Rob Adams
http://nextbigfuture.com/
September 01, 2015
NASA developing megawatt solar power arrays and will be used with solar electric propulsion
NASA Glenn Research Center, GRC, currently
has several programs to advance near-term photovoltaic array
development. One project is to design, build, and test two 20 kW-sized
deployable solar arrays, bringing them to technology readiness level
(TRL) 5, and through analysis show that they should be extensible to 300
kW-class systems (150 kw per wing). These solar arrays are
approximately 1500 square meters in total area which is about an
order-of-magnitude larger than the 160 square meters solar array
blankets on the International Space Station (ISS).
The ISS has the four (pair) sets of solar arrays that can generate 84 to 120 kilowatts of electricity. Each of the eight solar arrays is 112 feet long by 39 feet wide and weights 2400 pounds. There were space missions involving astronauts working in space to install and deploy the ISS solar panels.
Alliant Technical Systems, ATK, was selected in 2012 by NASA's Space Technology Program under a Game Changing Technology competition for development of a promising lightweight and compact solar array structure. The MegaFlex™ engineering development unit, EDU, was tested at NASA GRC Plumbrook facility this year. See below for the ATK deployment of the demonstration unit.
Use of high-power solar arrays, at power levels ranging from ~500 KW to several megawatts, has been proposed for a solar-electric propulsion (SEP) demonstration mission, using a photovoltaic array to provide energy to a high-power xenon-fueled engine. One of the proposed applications of the high-power SEP technology is a mission to rendezvous with an asteroid and move it into lunar orbit for human exploration (the Asteroid Retrieval mission). NASA is also exploring options for future power systems for extreme environments, including near-sun environments, solar electric propulsion, and operation on the Venus surface
The unit employs an innovative spar hinge to reduce stowed volume. Deployment is achieved in three stages: release from the spacecraft, unfolding the hinge, and rotating the wing. A single lanyard and motor operates the last two stages. The EDU is 10m in diameter and able to provide ~20kW BOL with TJ cells.
Similarly, Deployable Space System, DSS, developed a roll-out array, ROSA, EDU that employs an innovative stored strain energy deployment to reduce the number of mechanisms and parts. The elastic structure maintains stiffness throughout deployment for partially deployed power generation. The rectangular design can be configured in many ways by either lengthening the booms, adjusting the length and width, or attaching several winglets onto a deployable
backbone. Lengthening and/or shortening the booms provides power scaling without changing any of the subsystems or stowed configuration. See below for a fully deployed ROSA array.
* four 150 kilowatt wings would be 600 kilowatts in power. The new wings are easy to deploy and do not involve astronauts.
* eight 150 kilowatt wings would be 1.2 megawatts
Ion drives are ten to twenty times more fuel efficient than chemical engines.
Spider fab robotic assembly in orbit can get to 1 square kilometer or larger structures
Getting to 1 square kilometer would mean going from 1600 square meters and 150 kilowatts to 1 million square meters and 90 megawatts.
Here is the Spiderfab update.
Improving and testing reliability and a lot of engineering would be needed to get to 100 kilometer structures.
Making 6U cubesat trusselator to put out 50 meter trusses and make truss of trusses from several
They are using Baxter robot to work with trusselators.
The ISS has the four (pair) sets of solar arrays that can generate 84 to 120 kilowatts of electricity. Each of the eight solar arrays is 112 feet long by 39 feet wide and weights 2400 pounds. There were space missions involving astronauts working in space to install and deploy the ISS solar panels.
Alliant Technical Systems, ATK, was selected in 2012 by NASA's Space Technology Program under a Game Changing Technology competition for development of a promising lightweight and compact solar array structure. The MegaFlex™ engineering development unit, EDU, was tested at NASA GRC Plumbrook facility this year. See below for the ATK deployment of the demonstration unit.
Use of high-power solar arrays, at power levels ranging from ~500 KW to several megawatts, has been proposed for a solar-electric propulsion (SEP) demonstration mission, using a photovoltaic array to provide energy to a high-power xenon-fueled engine. One of the proposed applications of the high-power SEP technology is a mission to rendezvous with an asteroid and move it into lunar orbit for human exploration (the Asteroid Retrieval mission). NASA is also exploring options for future power systems for extreme environments, including near-sun environments, solar electric propulsion, and operation on the Venus surface
The unit employs an innovative spar hinge to reduce stowed volume. Deployment is achieved in three stages: release from the spacecraft, unfolding the hinge, and rotating the wing. A single lanyard and motor operates the last two stages. The EDU is 10m in diameter and able to provide ~20kW BOL with TJ cells.
Similarly, Deployable Space System, DSS, developed a roll-out array, ROSA, EDU that employs an innovative stored strain energy deployment to reduce the number of mechanisms and parts. The elastic structure maintains stiffness throughout deployment for partially deployed power generation. The rectangular design can be configured in many ways by either lengthening the booms, adjusting the length and width, or attaching several winglets onto a deployable
backbone. Lengthening and/or shortening the booms provides power scaling without changing any of the subsystems or stowed configuration. See below for a fully deployed ROSA array.
* four 150 kilowatt wings would be 600 kilowatts in power. The new wings are easy to deploy and do not involve astronauts.
* eight 150 kilowatt wings would be 1.2 megawatts
Ion drives are ten to twenty times more fuel efficient than chemical engines.
Spider fab robotic assembly in orbit can get to 1 square kilometer or larger structures
Getting to 1 square kilometer would mean going from 1600 square meters and 150 kilowatts to 1 million square meters and 90 megawatts.
Here is the Spiderfab update.
Improving and testing reliability and a lot of engineering would be needed to get to 100 kilometer structures.
Making 6U cubesat trusselator to put out 50 meter trusses and make truss of trusses from several
They are using Baxter robot to work with trusselators.
http://www.vox.com/
This is Boeing's Starliner: the spacecraft that will take astronauts to the space station
The Starliner (previously known as the CST-100) is a cone-shaped capsule designed to be launched into orbit atop a rocket, carrying up to seven people into space. Along with SpaceX's Dragon, it will run regular crewed missions to the space station, replacing NASA's Space Shuttle, which was retired in 2011.
Why Boeing is entering the human spaceflight business
(Boeing)
Subsequently, NASA selected SpaceX and the Orbital Sciences Corporation to carry out cargo missions to the space station, which began in 2012. Meanwhile, SpaceX and Boeing have been picked to handle missions transporting humans to and from the station. Those companies haven't started yet, so in the meantime, NASA has been paying Russia to shuttle its astronauts back and forth. The latest contract, signed in August, calls for NASA to pay more than $80 million per seat.
Plans originally called for Boeing and SpaceX to begin flying this year, but that target has been repeatedly pushed back, mainly because Congress keeps under-allocating the money needed to pay for the program. Things have gotten so bad that NASA administrator Charles Bolden recently wrote a public letter chastising Congress for the lack of funding, and blaming lawmakers for the $490 million that will be given to Russia as part of the new contract.
Still, NASA plans for flights to start in 2017 or 2018. The opening of Boeing's Starliner facility is an important step.
How the Starliner will work
(Boeing)
Design-wise, the Starliner is not quite as innovative as SpaceX's Dragon. Boeing seems to be emphasizing reliability instead. It closely resembles NASA's own Orion capsule (which will eventually be used for crewed missions to deep space), and the company touts its "heritage hardware," which is based off designs used in previous missions. The parachutes, for instance, were adapted from those used in the Apollo missions to the moon.
So far, Boeing has conducted several types of tests on the ground, as well as a 2012 drop test that involved dropping it from 14,000 feet to assess its parachutes and airbag landing system. The company plans for the first test flight in 2016 — and if all goes to plan, crewed missions will follow the next year.
Curiosity Rover Confirms Ancient Lake Filled Gale Crater, Boosting Chance of Life
by Ken Kremer on October 11, 2015
A view from the “Kimberley” formation on Mars taken by NASA’s Curiosity rover.
The strata in the foreground dip towards the base of Mount Sharp, indicating flow of
water toward a basin that existed before the larger bulk of the mountain formed. This
image was taken by the Mast Camera (Mastcam) on Curiosity on Sol 580 of the mission
and has been “white balanced” to adjust for the lighting on Mars make the sky appear light
blue. Credits: NASA/JPL-Caltech/MSSS
Hot on the heels of NASA’s groundbreaking announcement on Sept. 28 of the discovery that “liquid water flows intermittently” across multiple spots on the surface of today’s Mars, scientists leading NASA’s Curiosity rover mission have confirmed that an ancient lake once filled the Gale Crater site which the robot has been methodically exploring since safely landing back in August 2012 near the base of a layered mountain known as Mount Sharp.
The new research finding from the Curiosity team was just published in the journal Science on Friday, Oct. 9, and boosts the chances that alien life may have taken hold in the form of past or present day Martian microbes.
The article is titled “Wet Paleoclimate of Mars Revealed by Ancient Lakes at Gale Crater,”
with John Grotzinger, the former project scientist for the Mars Science Laboratory (MSL)
mission at the California Institute of Technology in Pasadena, as lead author of the new report.
Simulated view of Gale Crater Lake on Mars. This illustration depicts a lake of
water partially filling Mars’ Gale Crater, receiving runoff from snow melting on
the crater’s northern rim. Credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
The new study is coauthored by four dozen team members intimately involved in
Curiosity’s ongoing exploits and “confirmed that Mars was once, billions of years ago,
capable of storing water in lakes over an extended period of time.”
“Observations from the rover suggest that a series of long-lived streams and lakes
existed at some point between about 3.8 to 3.3 billion years ago, delivering sediment
that slowly built up the lower layers of Mount Sharp,” said Ashwin Vasavada, current
MSL project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California,
and co-author of the new report, in a statement.
Over the past three years, the Curiosity Mars Science Laboratory rover has been traversing the floor of Gale Crater investigating scores of different rocks and outcrops with her suite of state-of-the-art instruments, and painstakingly analyzing drill samples cored from their interiors with
a pair of chemistry labs to elucidate the history of Mars based on NASA’s “follow the water”
mantra.
The soundness of NASA Mars exploration strategy has repeatedly borne fruit and is now validated by overwhelming measurements gathered during Curiosity’s epic Martian trek confirming the existence of a lake where Mount Sharp now stands.
Exploring the sedimentary layers of Mount Sharp, which towers 3.4 miles (5.5 kilometers) into the Martian sky, is the primary destination and goal of the rovers long term scientific expedition on the Red Planet.
Since the nail biting touchdown on Aug. 5, 2012, Curiosity has been on a path towards the sedimentary layers at the lower reaches of Mount Sharp at the center of Gale Crater.
water toward a basin that existed before the larger bulk of the mountain formed. This
image was taken by the Mast Camera (Mastcam) on Curiosity on Sol 580 of the mission
and has been “white balanced” to adjust for the lighting on Mars make the sky appear light
blue. Credits: NASA/JPL-Caltech/MSSS
Hot on the heels of NASA’s groundbreaking announcement on Sept. 28 of the discovery that “liquid water flows intermittently” across multiple spots on the surface of today’s Mars, scientists leading NASA’s Curiosity rover mission have confirmed that an ancient lake once filled the Gale Crater site which the robot has been methodically exploring since safely landing back in August 2012 near the base of a layered mountain known as Mount Sharp.
The new research finding from the Curiosity team was just published in the journal Science on Friday, Oct. 9, and boosts the chances that alien life may have taken hold in the form of past or present day Martian microbes.
The article is titled “Wet Paleoclimate of Mars Revealed by Ancient Lakes at Gale Crater,”
with John Grotzinger, the former project scientist for the Mars Science Laboratory (MSL)
mission at the California Institute of Technology in Pasadena, as lead author of the new report.
Simulated view of Gale Crater Lake on Mars. This illustration depicts a lake of
water partially filling Mars’ Gale Crater, receiving runoff from snow melting on
the crater’s northern rim. Credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
The new study is coauthored by four dozen team members intimately involved in
Curiosity’s ongoing exploits and “confirmed that Mars was once, billions of years ago,
capable of storing water in lakes over an extended period of time.”
“Observations from the rover suggest that a series of long-lived streams and lakes
existed at some point between about 3.8 to 3.3 billion years ago, delivering sediment
that slowly built up the lower layers of Mount Sharp,” said Ashwin Vasavada, current
MSL project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California,
and co-author of the new report, in a statement.
Over the past three years, the Curiosity Mars Science Laboratory rover has been traversing the floor of Gale Crater investigating scores of different rocks and outcrops with her suite of state-of-the-art instruments, and painstakingly analyzing drill samples cored from their interiors with
a pair of chemistry labs to elucidate the history of Mars based on NASA’s “follow the water”
mantra.
The soundness of NASA Mars exploration strategy has repeatedly borne fruit and is now validated by overwhelming measurements gathered during Curiosity’s epic Martian trek confirming the existence of a lake where Mount Sharp now stands.
Exploring the sedimentary layers of Mount Sharp, which towers 3.4 miles (5.5 kilometers) into the Martian sky, is the primary destination and goal of the rovers long term scientific expedition on the Red Planet.
Since the nail biting touchdown on Aug. 5, 2012, Curiosity has been on a path towards the sedimentary layers at the lower reaches of Mount Sharp at the center of Gale Crater.
Curiosity rover panorama of Mount Sharp captured on June 6, 2014 (Sol 651)
during traverse inside Gale Crater. Note rover wheel tracks at left. She will
eventually ascend the mountain at the ‘Murray Buttes’ at right later this year.
Assembled from Mastcam color camera raw images and stitched by Marco
Di Lorenzo and Ken Kremer. Credit: NASA/JPL/MSSS/Marco Di Lorenzo
/Ken Kremer-kenkremer.com
But the origin of Mount Sharp has been up for debate.
With the new data, researchers believe that the ancient lake helped fill Gale Crater with sediments deposited in layers over time that formed the foundation for Mount Sharp which now dominates the center of the crater.
“What we thought we knew about water on Mars is constantly being put to the test,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program at NASA Headquarters in Washington.
“It’s clear that the Mars of billions of years ago more closely resembled Earth than it does today. Our challenge is to figure out how this more clement Mars was even possible, and what happened to that wetter Mars.”
Mars was far wetter and warmer and possessed a much more massive atmosphere billions of years ago than it does today.
An image taken at the “Hidden Valley” site, en-route to Mount Sharp,
by NASA’s Curiosity rover. A variety of mudstone strata in the area
indicate a lakebed deposit, with river- and stream-related deposits nearby.
This image was taken by the Mast Camera (Mastcam) on Curiosity on
Sol 703. Credits: NASA/JPL-Caltech/MSSS
Gale Crater lake existed long before Mount Sharp ever formed during that period billions of years ago when the Red Planet was far warmer and wetter.
“Paradoxically, where there is a mountain today there was once a basin, and it was sometimes filled with water,” said Grotzinger, in a statement.
“We see evidence of about 250 feet (75 meters) of sedimentary fill, and based on mapping data from NASA’s Mars Reconnaissance Orbiter and images from Curiosity’s camera, it appears that the water-transported sedimentary deposition could have extended at least 500 to 650 feet (150 to 200) meters above the crater floor.”
Indeed there is additional evidence that the sedimentary deposits from interaction with water may be as thick as one-half mile (800 meters) above the crater floor. However beyond that there is no evidence of hydrated strata further up Mount Sharp.
But for reasons we are still trying to decipher and comprehend, Mars underwent radical climactic change between 3 and 4 billion years ago and was transformed from an ancient wet world, potentially hospitable to life, to a cold, dry desiccated world, rather inhospitable to life, that exists today.
Featured on APOD – Astronomy Picture of the Day on May 7, 2014
Unlocking the mysteries, mechanisms and time periods of Mars climate change, loss of a thick atmosphere, ability to sustain liquid surface water and searching for organic compounds and for evidence of past or present habitable zones favorable to life are the questions driving NASA’s Mars Exploration program
Curiosity has already accomplished her primary objective of discovering a habitable zone on the Red Planet – at the Yellowknife Bay area – that contains the minerals necessary to support microbial life in the ancient past when Mars was far wetter and warmer billions of years ago.
NASA’s Curiosity rover looks back to ramp with potential 4th drill site target at
‘Bonanza King’ rock outcrop in ‘Hidden Valley’ in this photo mosaic view
captured on Aug. 6, 2014, Sol 711. Inset shows results of brushing on Aug.
17, Sol 722, that revealed gray patch beneath red dust. Note the rover’s partial
selfie, valley walls, deep wheel tracks in the sand dunes and distant rim of Gale
crater beyond the ramp. Navcam camera raw images stitched and colorized. Credit:
NASA/JPL-Caltech/Ken Kremer-kenkremer.com/Marco Di Lorenzo
“We have tended to think of Mars as being simple,” Grotzinger mused. “We once thought of
the Earth as being simple too. But the more you look into it, questions come up because you’re beginning to fathom the real complexity of what we see on Mars. This is a good time to go back to reevaluate all our assumptions. Something is missing somewhere.”
As of today, Sol 112902, October 10, 2015, she has driven some 6.9 miles (11.1 kilometers) kilometers and taken over 274,000 amazing images.
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
Ken Kremer
Curiosity Mars rover captured this panoramic view of a butte called
“Mount Remarkable” and surrounding outcrops at “The Kimberley
” waypoint on April 11, 2014, Sol 597. Colorized navcam photomosaic was
stitched by Marco Di Lorenzo and Ken Kremer. Credit: NASA/JPL-Caltech/
Marco Di Lorenzo/Ken Kremer – kenkremer.com
About Ken Kremer
Dr. Ken Kremer is a speaker, research scientist, freelance science journalist (Princeton, NJ) and photographer whose articles, space exploration images and Mars mosaics have appeared in magazines, books, websites and calendars including Astronomy Picture of the Day, NBC, BBC, SPACE.com, Spaceflight Now and the covers of Aviation Week & Space Technology, Spaceflight and the Explorers Club magazines. Ken has presented at numerous educational institutions, civic & religious organizations, museums and astronomy clubs. Ken has reported first hand from the Kennedy Space Center, Cape Canaveral, NASA Wallops, NASA Michoud/Stennis/Langley and on over 40 launches including 8 shuttle launches. He lectures on both Human and Robotic spaceflight - www.kenkremer.com. Follow Ken on Facebook and Twitter
Here's how the first humans will live on Mars — and why traveling the 140 million miles to get there will be the easy part
By Jessica Orwig
September 16, 2015 2:45 PM
View photo
In one word: Miserable.
Mars is a lifeless wasteland that would make Siberia feel like an island paradise.
But the frigid temperatures,
lack of breathable oxygen, and dangerous radiation levels are only some
of the many features that would make life on Mars a veritable,
red-stained hell.
Winters would be twice as long
and harsher than anything on Earth. And while there is water on Mars,
it's all locked in ice. Still think it's worth going to live on Mars?
TED speaker and technologist Stephen Petranek thinks so — enough to write an entire book on "How We'll Live on Mars." And the producers at TED have summed up the main points in Petranek's book in this amazing graphic.
Check it out below, and learn how the first human Martians will live:
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