Artist’s view of the James Webb Space Telescope (JWST) in space, up and operating tackling a full agenda of space science conquests.
Credit: Northrop Grumman


The James Webb Space Telescope (JWST) is the planned successor to the Hubble Telescope. Costs for the project have already increased by 95% and the launch date has been delayed by more than 6.5 years.

A new Government Accountability Office (GAO) report flags the fact that technical challenges have caused schedule strain and may increase costs. For JWST there is little margin for error and there are challenges with integration and test work ahead.



Rescheduled launch date

Technical issues with certain JWST components in 2019 have made it unfeasible for the project to launch by its goal of November 2020. Instead, the project is working towards its official rescheduled launch date of March 2021. But a recent cost and schedule analysis for JWST that GAO recommended in its last report, found the project unlikely to meet this date.

The GAO report notes that the JWST project has made significant progress since its last report in March 2019, such as completing testing of the observatory’s individual elements and integrating them together in August 2019.

JWST’s combined science instruments and optical element recently completed 100 days of thermal vacuum testing inside NASA Johnson Space Center’s Chamber A. Engineers are seen by the hardware shortly after it emerged from the huge test facility on December 1, 2017.
Credit: NASA/Chris Gunn

New technical challenges

“However, new technical challenges have required the project to use more schedule reserve—extra time set aside in the project’s schedule to accommodate unforeseen risks or delays—than planned.”

As of October 2019, the JWST project had used about 76 percent of its available schedule reserve and no longer plans to launch in November 2020. The project is now managing to a March 2021 launch date but estimates only 12 percent likelihood that this date will be achieved.

NASA plans to reassess the launch date in the spring of 2020.

For more information on this GAO document — JAMES WEBB SPACE TELESCOPE: Technical Challenges Have Caused Schedule Strain and May Increase Costs go to:

A hightlights overview of the report can be read at:

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