Spaceflight Insider

Our SpaceFlight Heritage: JWST – the once and future thing

Artist's rendition of the James Webb Space Telescope in space

Artist’s rendition of the James Webb Space Telescope in space. Image Credit: Northrop Grumman

Conceived in 1989 by the Space Telescope Science Institute and backed by NASA’s Goddard Space Flight Center, the Next Generation Space Telescope (NGST), predecessor to the James Webb Space Telescope, was to succeed the Hubble Space Telescope. The journey that the JWST would take has been a long and winding one.

The initial proposal, which had boasted an 8-meter (26.2 feet) primary mirror to view space in the near-infrared, was halted in 1990 when Hubble experienced a problem with its main mirror. This caused the Hubble telescope to be near-sighted and would lead to a repair mission carried out by the crew of STS-61, flown on the Space Shuttle Endeavour in 1993.

With Hubble’s spherical aberration corrected, HST’s path was clear to begin rewriting what humanity knew about the universe. For the JWST, however, its woes were only just beginning.

The NGST project was restarted in 1995 and it was determined in 1996 that if a space-based, near-infrared telescope was to be successful, it must orbit beyond the Moon’s orbit around the Earth, at the second Lagrange point (L2) of the Sun-Earth system, and utilize a sunshield.

James Webb Space Telescope insignia. Image Credit: NASA

James Webb Space Telescope insignia. Image Credit: NASA

By the end of 2000, the NGST team had finalized their instrument package and were already $100 million over the $500 million budget. Due to this extra cost and the time that it would take to make the 8-meter primary mirror, a scheduled launch was made for sometime in 2008. The NGST’s primary mirror was also reduced in diameter from 8 meters (26.2 feet) to 6.5 meters (21.3 feet) in 2001.

In 2002, the NGST was renamed the James Webb Space Telescope (JWST), after NASA’s administrator James Webb, and it underwent another planning phase to account for the changes made to the budget. Factoring in the time-consuming manufacturing process of the primary mirror segments, the launch date was pushed back until August of 2011.

In 2004, several issues arose during the design phase including reducing angular momentum and torque on the spacecraft. With the approval to use the Ariane 5 rocket in early 2005, more problems arose: financial issues due to the cost of completion increasing from $2 billion to $3.5 billion and a design flaw causing the JWST to be over the weight limit set by the team. These problems moved the launch date to no earlier than June of 2013.

Early 2006 got off to a promising start for the JWST team after passing the design review. Further testing later in the year showed the spacecraft would be able to withstand the temperatures and vibrations experienced during launch and after deployment.

In 2007, the technology that was to be used on the JWST passed all ten of the different testing phases, and in 2008, the spacecraft passed another design review and was cleared to begin the implementation and testing phases. However, due to government budgeting changes in 2009, the JWST launch was pushed back yet again to June 2014.

Things really looked bad for the JWST in 2011 when the United States House of Representatives’ appropriations committee on Commerce, Justice, and Science moved to cancel the JWST. The cost overruns, it appeared, had finally caught up with the telescope. However, the JWST was not dead yet.

In November of 2011, Congress reversed its plans to cancel the JWST, opting instead to cap the project’s budget at a staggering $8 billion.

The JWST did not hit another bump until early 2013 when the thermal shield was delayed. Additional technical concerns and further delays of delivered parts impacted the spacecraft’s deployment for the remainder of 2013 into 2014 along with the late assembly of the major components including the cryocooler, welding issues, and government delays.

As of June 2015, about 75 percent of the hardware was in place. Early 2016 showed the JWST was experiencing vertical shaker issues and a few parts were redesigned later this year. At present, the James Webb Space Telescope is currently scheduled to launch in October of 2018 from Kourou, French Guiana. All appearances suggest that the space-based observatory is progressing through implementation and testing without major delays.

 

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Mackenzie Kane is currently working towards receiving her Bachelors degree in Planetary Sciences and Physics at the Florida Institute of Technology. For the past several years, Kane's area of active research has been with NASA's Kepler Space Telescope mission and its search for extrasolar planets. Kane has a deep love of learning about the mysteries that space holds through the ever-growing technology that is launched into orbit. My goal upon graduation is to continue writing about the exciting research and technology furthering our presence in space and delivering it to the public in easily accessible ways. Kane was accepted as the second intern from Florida Tech to write for SpaceFlight Insider and our outlet will now work to provide her with access and experience.

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