Eu finalmente encontrei o livro enquanto procurava por minha outra pergunta aberta; soa um pouco diferente, mas eu tenho certeza que isso foi Homesmind, por Pamela Sargent .
Da descrição da Amazon:
"Anra is a solitary. She was born without the power to mindspeak and cannot, like all of her fellows can, communicate in unspoken thoughts. In the past, she would have been killed at birth but the arrival of the Wanderer, the comet controlled by the cybernetic intelligence known as the Homesmind has changed everything. The people of the comet, the skydwellers, now supply solitaries with implants that allow artificial mindspeaking. The solitaries are sequestered in a single village willing to care for such children. Anra and her new brethren were thought to be the possible bridge between the people of Earth and the skydwellers but the gap may be too great since the people of Earth consider solitaries an abomination and the skydwellers as soulless. The solitaries are, instead, outcasts in two worlds, part of each but fully accepted in neither. Another comet enters the system, refusing to communicate with Homesmind and speaking to the people of Earth with the voices of their own dead, seducing them into a submission of their individual wills and trying to lure them to oblivion. Anra and he fellow solitaries have the power to resist their call but can they unite in time to save everyone else? "
Eu não tinha percebido que era parte de uma série, nem que havia outro cometa envolvido, nem a segregação pouco ... bem, eu estava no estádio, eu acho.