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Breakthrough Starshot Sail RFP

Breakthrough Starshot held an ‘industry day’ on Wednesday May 23rd devoted to its lightsail project to take nanocraft to another star, framing the release of a Request for Proposals during its early concepts and analysis phase. The RFP focuses on the sail itself, investigating sail materials and stability under thrust. Step A proposals are due June 22, step B proposals on July 10, with finalists to be notified and contracts awarded this summer. The intent of the RFP is laid out in documents and slides from the meeting that Breakthrough has now placed online.

From the RFP itself:

The scope of this RFP addresses the Technology Development phase – to explore LightSail concepts, materials, fabrication and measurement methods, with accompanying analysis and simulation that creates advances toward a viable path to a scalable and ultimately deployable LightSail.

We’ve been talking about Breakthrough Starshot in these pages for a long time, as a search through the archives will reveal. The intention is to send gram-scale probes commonly referred to as ‘starchips’ attached to sails on the scale of meters to a nearby star to investigate its planets, with the highly interesting Proxima Centauri b an obvious target given that it is also the closest star to the Sun. Propelling the sail will be a gigawatt-scale ground-based laser. 20 years of flight time sets up the flyby, with data transmission returning images of the star system.

$100 million in research and development is to be spent over the next 5 years to determine the feasibility of both laser and sail. Overall, the five-year technology development period will be managed by three groups: Starshot’s sail committee, a photon engine committee and a systems engineering committee. After that, the goal from years 6 to 11 is to build a low-power prototype for space testing. After that comes a full scale laser system (called the ‘photon engine’) over the next 20 years, with launch of an interstellar mission occurring in approximately 30 years.

It’s an ambitious schedule, to be sure, but the early conceptual steps are now being taken, with initial sail work investigating candidate materials and sail stability. Keeping a sail stable under the high accelerations induced by the laser array is obviously critical and has already involved discussions and papers on different sail configurations, while the equally critical issue of sail materials is likewise considered in the RFP, which is Phase 1 of the sail’s development.

Phase 2 of the technology development program for the lightsail will validate lightsail materials and stable designs by proof of concept laboratory demonstrations, while Phase 3 takes us into laboratory testing of scalable prototypes. All of this points toward the eventual goal of a prototype mission that would launch nanocraft to a target here in the Solar System.

With this RFP focusing on Phase 1, Breakthrough Starshot seeks proposals for quantitative models that can produce testable predictions of sail performance, mathematical models defining the necessary conditions for sail stability, experimental methods for lightsail material fabrication and precision measurements to ‘validate optical, thermal and mechanical stability of materials.’ Here is the RFP statement of key issues involved in identifying candidate materials and designs:

  • Design of a reflector consistent with the mission requirement of achieving 0.2c for ~1g payload and LightSail area of >1 m2
  • Design of passive, adaptive or active features that enable or enhance stability, damage resistance, thermal robustness, and durability under deformation
  • Assessment of candidate materials (including thin-films, micro/nanopatterned structures, 2D materials) for thermal/mechanical stability
  • Development of measurement techniques and protocols for LightSail material properties (absorption, reflectivity, temperature, stress state, etc.)
  • Identification of materials for which scale-up and manufacture at the >1 m2 scale is feasible
  • Materials that facilitate integration of the LightSail with the Starchip
  • Development of the next generation Starchip scale spacecraft with a path towards incorporation into the Nanocraft

The second objective of the RFP is to identify and assess optimally-shaped designs for a stable sail that can withstand the temperatures and accelerations involved in pushing nanoncraft to 20 percent of the speed of light in a matter of minutes. The RFP notes the key issues here as:

  • Validation via, e.g., multi-physics simulation (optical, mechanical, thermal, etc.) of LightSail durability and dynamic stability and sensitivity to Photon Engine laser propulsion beam geometry and ground demonstrations
  • Evaluation of spacecraft stability in the context of a LightSail integrated with a Starchip payload
  • Development of optimization-based tools for evaluating LightSail designs matched to corresponding laser beam profiles.
  • Defining a roadmap for test and verification, including:
    o Measurement techniques for thin membranes at a small (<1 cm2) scale
    o Developing diagnostics and instrumentation needed for LightSail stability

You can download the RFP from the Breakthrough Starshot site for bidding information; note that multiple awards are anticipated. A layout of the proposal process and requirements is provided there, with submission information. The procurement is a two-step process with initial (short) white paper proposal evaluated by the Starshot lightsail committee and experts in beamed propulsion, and a second round in which finalists are invited to make final proposals. Contract negotiations will then be performed by the Starshot lightsail committee.


Comments on this entry are closed.

  • Ann Finkbeiner June 4, 2018, 12:03

    I’m sure those systems engineers have this figured out but I wonder whether, since the laser and the sail have to act as one system, they shouldn’t be designed together rather than through separate RFPs?

  • Robert June 4, 2018, 12:43

    Gigawatt scale lasers may be as problematic as using thermonuclear devices as far as the potential to apply the technology for military or political leverage. Their development may be dangerous to humanity.

    • Thomas Goodey June 4, 2018, 15:10

      In that exact connection, refer to the fine books by Alexis Gilliland, ‘The Revolution from Rosinante’, ‘Long Shot for Rosinante’, and ‘The Pirates of Rosinante’. They are all available on Kindle from Amazon.

    • Antonio June 4, 2018, 15:36

      Well, Orion-like fusion propulsion is certainly problematic, but I don’t think so for the other fusion propulsion schemes.

    • Adam June 5, 2018, 7:07

      Lasers that beam gigawatts for minutes at a target a few metres wide, thousands of kilometers away in space, might sound like they’d be useful as weapons, but what they’d lack is stealth.

    • charles quarra June 5, 2018, 14:58

      Anything worth pursuing may be dangerous to humanity.

    • Brett Bellmore June 7, 2018, 8:06

      That’s exactly why they’re proposing to station it on Earth, despite the obvious problems with firing that powerful a laser up through the atmosphere: So that it can’t actually be pointed at anywhere on Earth.

      From that perspective, of course, the far side of the Moon would be even better. No atmosphere to worry about, and can’t be pointed at satellites, either.

      But I understand the advantage of the hardware being easily accessible might be seen to weigh more strongly than having to deal with going through air.

      My real conclusion is that this is unlikely to actually be built prior to us becoming an interplanetary civilization, and so the advantages of stationing it in space will prevail.

  • Thomas Goodey June 4, 2018, 15:15

    I don’t think it has a hope of working. No process is 100% efficient, and in this case, the inefficiency of the light driving the sail will manifest itself as heat, which will blow the sail and the payload to smithereens, nay into plasma.

    Moreover, the idea that a useful payload could mass a few grams is utterly visionary. It might happen, but spending money (let alone $100 million) on the supposition that it will happen is far too speculative.

    • Patient Observer June 5, 2018, 19:41

      I agree that the technology appears far beyond any extrapolation of present capabilities. Lets first see what could be done with these grams of sensors and communication hardware in our solar system.

  • DCM June 4, 2018, 15:37

    “Their development may be dangerous to humanity.”
    Don’t give anyone else any ideas.

  • Thomas R Mazanec June 4, 2018, 16:27

    What resolution of any Centauran exoplanets would this system have again?

    • Paul Gilster June 4, 2018, 21:08

      Still to be determined, as are so many of the parameters. Breakthrough Starshot is extremely early in the conceptual process.

  • Neil S June 4, 2018, 19:22

    I presume one overriding reason for having the laser bank on the ground is so it can’t be aimed at someone’s country. And it might be of value in deflecting a comet or asteroid threatening us a few orbits later.

  • Thomas Hair June 5, 2018, 5:49

    We have had the ability to destroy the human race since July of 1945 with the Trinity shot near Alamogordo, yet we have not done so in the intervening years. Call me a naive or even foolish optimist, but I place my trust in my fellow man/woman. We will reach the stars. It may be very very hard, but it’s the hard that makes it worth doing.

    • Antonio June 5, 2018, 15:18

      I think we don’t have the ability to destroy the human race even now. We are far from that.

      • Brett Bellmore June 7, 2018, 8:08

        We’ve had the technology to destroy the human race, we never built the hardware necessary to do it. Current nuclear stocks probably wouldn’t even destroy civilization, though they’d do a great job of setting it back a few decades.

        • Thomas Hair June 7, 2018, 22:16

          In 1984 they would have been able to come close. There were over 30,000 deliverable weapons at that time, many of megaton power. I was a pilot in the the US Navy at that time and have some understanding…it was a very dangerous time. Thanks to Reagan and Gorbachev and like minds in the intervening years we now have the luxury of a muddled view of history. I am old enough to remember the concept of nuclear winter which Carl Sagan so eloquently brought to the attention of the common man/woman.

          • Antonio June 9, 2018, 2:14

            Nope, the nuclear winter could kill a lot of people, but not extinct us.

            • J. Jason Wentworth June 10, 2018, 6:11

              The nuclear winter prediction was based on a fixed Sun, relative to the Earth’s rotation–which, of course, the Sun isn’t. Carl Sagan’s prediction that starvation in Asia would likely result due to nuclear winter-like effects from Saddam Hussein setting the oil wells on fire also did not happen. This is not to suggest that nuclear war should be taken lightly, but crying wolf when there’s no wolf around isn’t wise, either.

              • ljk June 11, 2018, 10:00

                Oil well fires in Iraq are nothing compared to what even a “limited” nuclear war could do to Earth:




                Amazing that there were people then and even now using this error by Sagan as an excuse to say a nuclear war was “winnable” like this did in the 1950s, when they did not have a full appreciation of how terrible a nuclear blast could be, despite having two cities in Japan to learn from. Of course some of them knew but the military and politicians purposely downplayed just how bad a nuclear attack would be.

                Look at what non-nuclear disasters do to society and then imagine one where whole cities are obliterated.

  • ljk June 5, 2018, 9:45

    We should have used Orion, and I don’t mean the current NASA version:


    As I speculated in the above article two years ago, I can think of one nation in particular that has the ability, resources, and remote places to make Orion happen. Most importantly, they also have the drive.


    • Antonio June 7, 2018, 16:35

      Probably it would be easier to build Zubrin’s nuclear salt water rocket, both politically and technically.

      • ljk June 8, 2018, 9:34

        Whatever works, so long as it actually works and doesn’t get lost as such projects can that take decades to become a reality.

  • Aleksandar Shulevski June 5, 2018, 10:14
  • tesh June 5, 2018, 11:53

    If the idea is to fire a laser from earth, what are the likely effects on the atmosphere, potential air traffic and space traffic?

    Outwith of some maniacal figure taking over the controls of the laser, it would make more sense to launch it into space and puch the sail from there.

    • Adam June 5, 2018, 14:15

      Putting it in space is the worst idea for Earth security. On the ground its utility as a weapon is minimal. Also it’s infrastructure makes it infeasible to locate in space and completely vulnerable to countermeasures. Firing for only minutes at a time, but taking days to recharge, it has no ability as a rapid fire system.

      • Brett Bellmore June 7, 2018, 8:10


        I’d have thought that, while you might use power storage to produce gigawatts for seconds at a time, when you’re talking 20 minutes, you’re probably better off investing your money in power lines and buying the power off peak.

  • Neil S June 6, 2018, 4:41

    If in fact it does take days to charge then it can be kept discharged except when it’s needed and observers could be stationed there to insure it’s not charged up. If it’s used to clear orbiting junk, which would seem to be a good use, then there would need to be strict protocols and enforcement mechanisms so it couldn’t be used to destroy some space assets. And a large orbiting mirror might need to be outlawed. But it should be possible to have it available without allowing it to be used as a wmd.

    • Brett Bellmore June 7, 2018, 8:14

      You’d only need a tiny fraction of the full power for destroying orbital junk. For the most part a few megawatts might be overkill, you’d use a pulsed laser to evaporate material off one side of the junk, to produce thrust to deorbit it.

      I think that’s the sort of thing that you might accomplish with a module added to the ISS, rather than a ground based system capable of gigawatts for minutes. There you’re getting into asteroid deflection power levels, not space junk removal levels.

  • Michael June 6, 2018, 16:15

    OMG I am going to need a bigger Napkin !

  • J. Jason Wentworth June 8, 2018, 3:47

    I am glad that the Breakthrough Starshot RFP has finally been issued. Freeman Dyson’s comment about the project, recorded in the March 2017 “Scientific American” article (linked-to in Paul’s posting above), that “…it’s silly. But the spacecraft is interesting,” may turn out to be correct. But since we don’t know, and because the project looks like it will be privately funded, let them try; they may succeed, and:

    I do wonder if 0.2 c flybys of the Alpha Centauri stars and planet(s) would be able to gather meaningful data and/or images, but we can find out without going 4.3 light-years. Making such rapid flybys of planets–and our Sun–in our own Solar System would demonstrate what could be done. Perhaps a stream of such fleet probes, each one collecting the equivalent of one motion picture frame of camera, radiometer, spectrometer, polarimeter, and magnetometer data, might make it possible (through binning techniques, say) to generate pictures and instrument reading “snapshots,” which could be stitched together into image and instrument reading sequences. Also:

    The full-power laser array (the photon engine) looks like a mighty big technological leap, but so was the atomic bomb (and all of its previously-nonexistent production technologies). In that connection, the full-power photon engine, if it could be realized, would also have numerous defense-related and solar system space exploration and space exploitation applications. These could include (but would not necessarily be limited to):

    [1] Planetary defense. Focused on a potentially hazardous asteroid (or short-period comet), vaporization of a small percentage of its surface material would produce rocket thrust, altering its orbit so as to ensure that it would miss the Earth. If need be (or perhaps to extend its effective range), an orbiting mirror or Fresnel lens (like that used in Robert Forward’s laser sail starprobe and starship proposals, only much smaller), perhaps in geostationary orbit, might be used;

    [2] Satellite and ballistic missile defense. With the aid of one or more orbiting (perhaps geostationary) mirrors or Fresnel lenses, the ground-based laser array could be used to destroy satellites and ballistic missiles. This capability would also have an important environmental benefit, by clearing near-Earth space of the ever-growing numbers of dead satellites, launch vehicle final stages, and collision fragments, which are making Earth orbits more and more dangerous for operational spacecraft as time goes on. Such an orbital lanes clean-up would be necessary before a space elevator (orbital tower) could be seriously planned, and;

    [3] The laser array (photon engine) could also be used to power unmanned and manned spacecraft of all kinds. These could include photovoltaic cells-powered electric propulsion and solar thermal propulsion (solar rockets, using hydrogen, ammonia, or even water for propellant) space probes, lunar shuttles, LEO-to-GEO space tugs, asteroid prospecting vessels, and interplanetary spaceships.

    • Alex Tolley June 8, 2018, 10:11

      and because the project looks like it will be privately funded

      Only the basic feasibility is funded. To actually send a probe to a star requires at least a couple of orders of magnitude more funding.

      The DoD is funding Lubin’s lasers for planetary defense (at least that is what is presented to the public AFAICS, but if you believe that I have a bridge to sell you… *smile*). I somewhat doubt that any system would be able to handle strikes like the Chelyabinsk meteor unless we have far better monitoring systems. Clarke’s Spaceguard idea is far from actually being a reality.

      • J. Jason Wentworth June 10, 2018, 6:33

        We must crawl before we can walk. Just as Goddard’s and Korolev’s feeble creations were necessary preludes to today’s ballistic missiles and launch vehicles (whose development required government funding), so too must basic, low-powered laser arrays be built before we can learn how to build, accurately aim, and operate their powerful descendants that can deflect asteroids, de-orbit space junk, and propel star probes and other spacecraft, and:

        Our current ABMs (Anti-Ballistic Missiles) might be able to destroy Chelyabinsk-size impactors, if sufficiently fine tracking data could be obtained soon enough before entry. Russia’s nuclear-armed ABMs that surround Moscow (they have 200-kiloton warheads) could almost certainly destroy such objects, although warhead detonation in a preferred “altitude corridor” (too low, and airburst damage would occur on the ground; too high, and the EMP effects on electronics would result in a lot of fried equipment) would be preferable.

  • aden June 9, 2018, 7:55

    Probably a naive question, but how does the laser avoid frying the payload?

    • Paul Gilster June 9, 2018, 12:08

      Not a naive question at all, and one that Starshot will be addressing in the early sail work.

    • Michael June 9, 2018, 14:14

      The payload will be designed into ‘shadow’ areas.

      • Paul Gilster June 9, 2018, 15:43

        The beam can also be configured in interesting ways, but I’m going to leave that for a future post.

  • ljk June 13, 2018, 12:08

    Hawking’s microbot vision for Alpha Centauri edges closer


  • ljk July 6, 2018, 10:51

    Astronomy at the Speed of Light

    Future space probes traveling at relativistic velocities would offer a unique vantage point for studying the Universe.

    By Bing Zhang, The Conversation US on July 3, 2018


    To quote:

    With the projected technology development rate, it will likely be at least two more decades before scientists can launch a camera traveling with a speed a significant fraction of the speed of light.

    Even if such a camera could be built and accelerated, several more challenges must be overcome in order to fulfill the dream of reaching the Alpha Centauri system. Can researchers aim the cameras correctly so they reach the stellar system? Can the camera even survive the near 20-year journey without being damaged? And if it beats the odds and the trip goes well, will it be possible to transmit the data—say, images—back to Earth over such a huge distance?