NASA, European Space Agency Formalize Artemis Gateway Partnership NASA and ESA (European Space Agency) have finalized an agreement to collaborate on the Artemis Gateway. This agreement is an important element in a broad effort by the United States to engage international partners in sustainable lunar exploration and to demonstrate technologies necessary for a future human mission to Mars. http://www.nasa.gov/press-release/nasa-european-space-agency-formalize-artemis-gateway-partnership