A Colorado company that said last year it had achieved a technological breakthrough in space transportation has decided to shut down, citing the high costs and risks associated with further development.

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...