What are the consequences of making cyberspace increasingly reliant on satellites and other types of space infrastructure? And what is the meaning and significance of an interplanetary cyberspace? The chapter addresses these developments specifically concerning infrastructure, militarization, and privatization. The consequences observed are summed up as fragmentation, vulnerability, and uncertainty. Cyberspace in space implies fragmentation in terms of stakeholders and governance, and ultimately in terms of power and accountability. Vulnerability increases as cyberspace becomes satellite-based (space is certainly not a safe environment, and satellites can be attacked by anti-satellite weapons as well as new forms of hacking and denial of service. Uncertainty of is tremendous particularly both in terms of what norms and principles will apply (compare the debate on Internet freedom vs. Internet sovereignty), and whether militarization or civilian and even utopian ideas will prevail.