51 U.S.C. § 20143 — Full cost appropriations account structure

(a) Accounts for Appropriations. (1) Money for the Administration^* must be appropriated into 3 accounts: 'Science, Aeronautics, and Education'; 'Exploration Systems and Space Operations'; and an account for the necessary expenses of the Office of the Inspector General. (2) Within the Exploration Systems and Space Operations account, no more than 10 percent of a fiscal year's Exploration Systems funds may be moved to Space Operations, and no more than 10 percent of that year's Space Operations funds may be moved to Exploration Systems — this limit does not apply to the transfers described in subsection (b)(2). (3) Appropriations stay available for 2 fiscal years unless a law says otherwise, and each account must include the planned full cost of the Administration's activities.

(b) Transfers Among Accounts. (1) To make sure Administration missions succeed safely, on time, and as intended, the Administration may transfer amounts among accounts as needed for (A) federal salaries and benefits; (B) training, travel, and awards; (C) facility and related costs; (D) information technology services; (E) publishing services; (F) science, engineering, fabricating, and testing services; and (G) other administrative services. (2) The Administration may also transfer amounts among accounts for the immediate costs of recovering from a major disaster (as defined in section 102 of the Robert T. Stafford Disaster Relief and Emergency Assistance Act, 42 U.S.C. 5122) or an act of terrorism, or for the immediate costs of an emergency astronaut rescue.

(c) Transfer of Unexpired Balances. Unexpired balances of earlier appropriations for activities under this chapter may be moved into the new account set up for that activity under subsection (a). Once moved, those balances may be combined with the new account's funds and then treated as one fund under the same terms and conditions.