Free Astronomy Magazine May-June 2016

ASTRONAUTICS beam. The modular and scalable array of lasers, cal- led “light beamer” will en- sure energy power be- tween 100 and 200 giga- watts (50 times the capaci- ty of the USA’s largest nu- clear power plant), of which only a portion will be need- ed for each single accelera- tion. Apart from the fact that the light beamer will have to be sited in a high- altitude dry environment, the main difficulty will be to synchronize and phase lock the laser beams pro- duced by the individual op- tical elements of the array, or even different arrays. The miniprobes will first be carried together at a high-altitude orbit by a standard carrier rocket and, given their small size, it will be necessary to know with extreme precision their position in space and the sail orienta- tion. Once the “target” is correctly position- ed and facing its destination, the laser beam will accelerate the miniprobe for a couple of minutes, sufficient for making it reach 20% of the speed of light (over 2 minutes the distance becomes already such that the laser consistency of performance becomes more difficult). The energy power required for each acceleration will have an estimated cost of at least $100,000, significantly higher (per- haps 100 times) than that required for build- A rtist’s ren- dering of the 100 gigawatts laser array. As shown below, each optical ele- ment will produce a beam synchro- nized and phase locked with the other. [Break- through Founda- tion]