NASA Administrator Bill Nelson said he is concerned about reports that Elon Musk, chief executive of SpaceX, has had discussions with Russian President Vladimir Putin.

This post is only available to members.

Jeff Foust has more than a decade of experience writing about space policy, entrepreneurial ventures and regulatory affairs. In 2001, he established spacetoday.net to aggregate and summarize the day's space-related news stories. In 2003, he started The...