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MNN.COM›Earth Matters› Space NASA working on space taxi? NBC space expert James Oberg discusses the next phase in U.S. space exploration after NASA retires the shuttle program in June. Read more: NASA, SCIENCE, SPACE, VIDEO You might also like: Related Topics: NASA, Science, Space, Video Related Videos Man completes triathlon, juggling all the way Plastic bag ban is great news, says Philippe Cousteau Jr. Understanding flesh-eating bacteria Wife's strength gives man courage to wear pink tutu Comments Follow this conversation Add your comment View: All (0) Add your comment Sign in with one of these accounts or just add your comment below. Log in or create an account     Enter your comments E-mail: Used only for emailed comments and will not be displayed with your post Follow this conversation Notify me with an email when other people comment on this article. The posting of advertisement, profanity or personal attacks is prohibited. Click here to review our Terms of Use

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