In January 2020,a rumor from California in the United States reached researchers and entrepreneurs in Europe,a thriving hub for the small,mostly trans-Atlantic field of engineering research and development called airborne wind energy (AWE):Alphabet,American technology giant Google's parent company,was quietly closing down Makani,the AWE subsidiary it had nurtured into the world's most advanced,visible,and well-funded enterprise designing and building tethered flying machines-kites in AWE parlance-intended ultimately to produce megawatts of wind energy.