51 U.S.C. § 50909

1. (a)The Secretary of Transportation may prohibit, suspend, or end immediately the launch of a launch vehicle or the operation of a launch site or reentry site, or reentry of a reentry vehicle, licensed under this chapter if the Secretary decides the launch or operation or reentry is detrimental to the public health and safety, the safety of property, or a national security or foreign policy interest of the United States.
2. (b)An order under this section takes effect immediately and remains in effect during a review under section 50912 of this title.