Project Solaris for enabling and then scaling space based light deflection

Project Solaris is to harness space based solar. It will use a distributed system composed of a multitude of small light deflecting units (cm-sized to µm-sized). These units will be uniformly scattered over a disc shaped plane and kept in place using different techniques (radiation pressure and/or electric fields and/or magnetic fields, or other methods). Easy deployment, fault tolerance and live scalability are some of the advantages that this system could provide.

[Image Credit: Nembo Buldrini]

Antimatter Creation

An additional exciting possibility that the availability of high energy densities would enable, is the mass production of the material with the highest known energy storage density, that is antimatter. Antimatter factories could be setup as close as possible to the Sun, and would be able to deliver antimatter for powering space vehicles and other space appliances

[Image Credit: Adrian Mann]

Going Interstellar!

Beaming power to large distances, as it would be needed in the case of supplying a spacecraft for propulsion, would require converting the solar light into laser light. Solar pumped laser would then be the natural choice. However, in order to reach “interstellar” distances, additional relay optics will be necessary, the structure of which can also be based on the distributed deflector concept. An example of this arrangement is the interstellar lightsail concept made famous by Robert Forward. The power collected by a 28 km radius deflector placed at 1/10 of the distance of Mercury from the Sun would be about 1PW, enough, considering also the solar light-to-laser conversion efficiency, to enable fast interstellar travel.

Project success will be defined by milestones:

I. First important milestone is to produce a sound model of distributed light deflector.

II. Second milestone is to build and deploy a minimal version of such a model in space: a distributed deflector of about 5 meters diameter capable of directing and concentrating at least 10 kW of solar light power (at the distance of Earth from the Sun: about 1300 W/m2). A rough estimate of the deflection efficiency of a distributed mirror is about 45%. This considers a distance between the units equal to their extension (which means a total of 50% deflecting area) and a 90% mean light deflection efficiency of the single units.

III. Third milestone is to test the modularity and the scalability: build and deploy in space a 50 meters diameter distributed deflector capable of managing more than 1 MW. And so on.

IV. The final fantastic target is to reach the PW power levels needed for interstellar missions.

Note that the W/m2 solar radiation figure used above is referred to a mirror at the same approximate distance of the Earth from the Sun. For more ambitious missions (TW, PW power levels), it is preferred to set the deflector in the vicinity of the Sun, in order to reduce the overall dimensions.

Patterned Changing Surface Reflectivity

One way to control the mirror unit position and rotation in space is to equip it with patches with adjustable reflectivity: this would allow to modify the solar radiation pressure distribution on its surface. This concept has been already demonstrated in space by the Japanese IKAROS experimental probe.

SOURCES – Icarus Interstellar