Government Accountability Office says NASA is at `` high risk '' of missing planned 2017 launch date of deep-space rocket . Audit estimates NASA may need $ 12 billion . Audit says schedule delays or fund diversions could result in increased costs to taxpayers .
Audit says NASA is at `` high risk '' of missing planned 2017 launch date of deep-space rocket . Government Accountability Office estimates NASA may need an additional $ 400 million . NASA says schedule delays or fund diversions could result in increased costs to taxpayers .