Editing Human spaceflight (section)

=== United States "Shuttle gap" ===
[[File:STS-135 begins takeoff (cropped).jpg|thumb|[[STS-135]] (July 2011), the final human spaceflight of the United States until 2018]]
[[File:Virgin Galactic SpaceShipTwo "Unity" rollout 19Feb2016, FAITH hangar, Mojave, California.jpg|alt=|thumb|[[VSS Unity|VSS ''Unity'']] [[VSS Unity VP-03|Flight VP-03]] December 2018, the first human spaceflight from the United States since [[STS-135]] ]]

Under the George W. Bush administration, the [[Constellation program]] included plans for retiring the Space Shuttle program and replacing it with the capability for spaceflight beyond low Earth orbit. In the [[2011 United States federal budget]], the Obama administration canceled Constellation for being over budget and behind schedule, while not innovating and investing in critical new technologies.<ref>[http://blogs.orlandosentinel.com/news_space_thewritestuff/2008/11/congressional-w.html Congressional watchdog finds NASA's new rocket is in trouble] {{webarchive|url=https://web.archive.org/web/20111129102151/http://blogs.orlandosentinel.com/news_space_thewritestuff/2008/11/congressional-w.html |date=29 November 2011 }}. Orlando Sentinel blog summary of official reports. 3 November 2008</ref> As part of the [[Artemis program]], NASA is developing the [[Orion (spacecraft)|Orion]] spacecraft to be launched by the [[Space Launch System]]. Under the [[Commercial Crew Development]] plan, NASA relies on transportation services provided by the private sector to reach low Earth orbit, such as [[SpaceX Dragon 2]], the [[Boeing Starliner]] or [[Sierra Nevada Corporation]]'s [[Dream Chaser]]. The period between the retirement of the Space Shuttle in 2011 and the first launch into space of [[SpaceShipTwo]] [[VSS Unity VP-03|Flight VP-03]] on 13 December 2018 is similar to the gap between the end of [[Apollo program|Apollo]] in 1975 and the [[STS-1|first Space Shuttle flight]] in 1981, and is referred to by a presidential Blue Ribbon Committee as the U.S. human spaceflight gap.