Key JWST Events
From conception to launch of the James Webb Space Telescope took 32 years and the hard work and dedication of thousands of individuals. The timeline below outlines key milestones in the history of the development of the James Webb Space Telescope, including the early planning of the observatory and the major steps in construction, up to its launch and its first observations.
NGST Workshop at STScI
"The Next Generation: A 10 m Class UV-Visible-IR Successor to HST" workshop is held at STScI to discuss the opportunities and challenges of the next mission beyond Hubble.
HST and Beyond Committee Appointed by AURA
At the behest of the Space Telescope Institute Council, and with support from NASA, AURA appoints the ‘HST and Beyond’ committee to study possible missions and programs for ultraviolet-optical-infrared (UVOIR) astronomy in space for the first decades of the twenty-first century.
Committee Recommends Space Telescope
The HST & Beyond Committee’s report recommends, as a successor to Hubble, a significantly larger telescope with capabilities in the ultraviolet-optical-infrared (UVOIR) range. NASA selects Goddard Space Flight Center and the Space Telescope Science Institute to study its feasibility. Three independent government and aerospace teams determine that such an observatory is feasible.
Industry Study Teams Are Formed
NASA selects teams from the GSFC, TRW, and Ball Aerospace to explore the telescope’s possible technical design and estimate financial requirements.
Yardstick Design Proposed
“The Next Generation Space Telescope: Visiting the Time When Galaxies Were Young” report laid out the yardstick design that showed a telescope like JWST was possible and provided information allowing NASA to issue the calls for proposal to industry. The report included input from a Science Oversight Committee chaired by Prof. R. Kennicut, NASA centers, academia, and industrial partners.
NASA Identifies Engineering Firms and International Partners
NASA chooses Lockheed Martin and TRW (which became Northrop Grumman Space Technology/Ball Aerospace in 2002) to conduct “Phase A” mission studies, preliminary analysis of the design, and cost. Instrument studies also include the participation of international partners — the European Space Agency and the Canadian Space Agency.
James Webb Space Telescope Gets Its Name
Based on two “Phase A” studies, NASA selects the design of TRW/Ball Aerospace to continue in “Phase B” detailed design studies, which examine the performance and cost of the chosen design. The telescope is renamed from the Next Generation Space Telescope to the James Webb Space Telescope. TRW, bought by Northrop Grumman, becomes Northrop Grumman Space Technology. NASA forms the Science Working Group to work in collaboration with the JWST Project, NASA Headquarters, and the astronomical community to provide coherent scientific leadership during the formulation, design, and early scientific operation of the JWST. NASA also identifies the team responsible for developing the Near Infrared Camera.
Construction Begins
Construction begins on certain telescope parts that require extensive, long-term work — in particular, Webb's science instruments and the 18 segments of the primary mirror.
JWST Science Working Group Defines Requirements
The JWST Science Working Group formally approves the science requirements that will drive the design of the mission.
Ariane 5 Rocket Approved
NASA approves the use of the European Space Agency-provided Ariane 5 rocket to launch Webb into its operating orbit.
First Instruments Pass Design Reviews
The science instrument teams for the Near Infrared Camera (NIRCam) and the Mid-Infrared Instrument (MIRI) pass their critical design reviews and initiate construction of the flight instruments. All Webb's essential technologies are tested successfully under flight conditions.
Main Construction Begins
NASA has the mission reviewed by internal and external groups. The internal “preliminary design review” and external “non-advocate review” concludes that the plans and designs have reached the maturity needed for NASA to commit to phases C and D. Phases C and D entail detailed design, procurement, testing, and assembly of telescope and observatory components. Construction begins in earnest.
Launch Tests Begin
The Integrated Science Instrument Module (ISIM) structure, which will house Webb's four science instruments, arrives at Goddard Space Flight Center for testing. These tests will verify the ISIM's ability to survive launch and the extreme cold of space, and to precisely hold the science instruments in the correct positions with respect to the telescope.
Design Review Passed
The James Webb Space Telescope passes its Mission Critical Design Review, which signifies that the integrated observatory will meet all science and engineering requirements for its mission. The sunshield also passes its critical design review, certifying that its design is complete and meets mission requirements.
Mirrors Completed
Webb's mirrors are completed. They have been polished and coated in gold, and they have passed cryogenic testing, which exposed them to the frigid temperatures they'll be subjected to in space.
First Instuments Delivered to Goddard
Goddard Space Flight Center receives two of Webb's four science instruments, the Mid-Infrared Instrument (MIRI) and the Near-Infrared Imager and Slitless Spectrograph (NIRISS), as well as Webb's Fine Guidance Sensor, from the European and Canadian space agencies. Webb's secondary mirror and the first three primary mirror segments also arrive at Goddard Space Flight Center from Ball Aerospace & Technologies Corp. Northrop Grumman and partner ATK finish constructing the center section of Webb's backplane structure, which will hold the telescope's primary mirror segments.
JWST Integration Continues
The two side “wings” of Webb's backplane structure that will hold the primary mirror segments are completed by ATK and Northrop Grumman. Webb's two final science instruments — the Near Infrared Camera (NIRCam) and Near Infrared Spectrograph (NIRSpec) — as well as the remaining primary mirror segments will be delivered to Goddard Space Flight Center.
Manufacturing and Cryogenic Testing
The 2014 period focuses on manufacturing the spacecraft and cryogenic testing. Northrop Grumman tests a full-scale engineering model of the sunshield to demonstrate the precision-folding and -unfolding necessary to protect the mirror and instruments from heat once in space. Manufacturing of the spacecraft parts, such as fuel tanks, gyroscopes and solar panels, begins. Cryogenic testing of the Integrated Science Instrument Module (ISIM), including all four instruments, demonstrates the performance of the instruments as well as the electronics used to communicate with the instruments.
Primary Mirrors Mounted
The 18 primary mirror segments are mounted into the backplane, along with the secondary mirror and support struts.
Optical Telescope Element Completed
The primary and secondary mirrors are integrated with the aft mirrors and the ISIM to create the unit known as the Optical Telescope Element.
Final Testing of Telescope and Instruments
Final test of the integrated telescope and science instruments at Johnson Space Center completed.
Cycle 1 General Observers (GO) Proposal Deadline
At least 1170 GO proposals were received in response to the JWST Cycle 1 Call for Proposals.
JWST Launch
JWST launches from Kourou, French Guiana on a European Space Agency's Ariane 5 rocket.
Webb's First Images Released
With the end of commissioning and the release of Webb's first images, the start of science officially begins.
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The NASA James Webb Space Telescope, developed in partnership with ESA and CSA, is operated by AURA’s Space Telescope Science Institute.