CORRECTIONS

摘要

The article "After Servicing the Space Station, SpaceX's Prior-ity is Taking on EELV" [April 18, page 4] should have said that ac-cording to a NASA-U.S. Air Force study, it would cost $4.5 billion to develop a Falcon 9-class medium lift rocket using traditional gov-ernment procurement practices.The article "NASA's CCDev 2 Awards Favor Capsules Over Launchers" [April 25, page 7] should have said the awards fa-vored crew vehicles over launchers.