Webb was first imagined for a 2007 launch at about $1 billion. After repeated replans it launched on 25 December 2021 with a NASA lifecycle estimate of $9.66 b…
NASA's Roman Space Telescope launched on 30 August 2026, which NASA called ahead of schedule and under cost against its replanned baseline.
NASA released Webb's First Deep Field on 11 July 2022 and four more targets on 12 July, when science operations began.
Webb launched at 7:20 am EST on an Ariane 5 from Kourou, after a clamp-band incident, a communications issue and weather moved the date.
NASA moved launch from 30 March 2021 to 31 October 2021 and tied about three of the seven months to pandemic precautions.
An independent board chaired by Tom Young set launch for 30 March 2021, with $8.8 billion development and $9.66 billion lifecycle cost.
NASA moved from October 2018 to spring 2019, then on 27 March 2018 to no earlier than May 2020.
A House committee recommended cancellation in July 2011; Congress kept funding with an $8 billion development cap.
The Casani panel found budgeting and management problems, not technical performance, and reserves that were too low.
$4.964 billion lifecycle, with launch in June 2014. GAO later measured about 95% cost growth against it.
Concept studies assumed a 2007 launch and about $1 billion, a concept-stage target, not a formal baseline.
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