Major elements of the James Webb Space Telescope (JWST) have been upgraded ahead of the observatory's launch in 2018. The Webb Telescope is sort of the next "bigger, badder" Hubble - a joint project between NASA, ESA and the Canadian Space Agency.
According to European Space Agency (ESA), Webb has a 6.5 m-diameter telescope and four state-of-the-art science instruments optimized for infrared observations.
The Webb Telescope will be tasked as an all-purpose observatory and will help with new discoveries in a wide range of topics, including detecting the universe's first galaxies, new star births and the ensuing planetary systems and studying our galaxy.
In April 2014, the four instruments in the telescope's Integrated Science Instrument Module (ISIM) were installed and since then, the module has undergone exhaustive testing to ensure its readiness for launch and operation, according to ESA. An important part of that testing included a 24-hour 116-day cryogenic test that was completed last summer.
After the cryogenic test, key components of instruments that needed additional work were replaced over the next several months. Europe's "NIRSpec," the near-infrared multi-object spectrograph, was upgraded. NIRSpec will split infrared light into a spectrum, giving scientists crucial information on chemical composition, age and distance. The first installation of NIRSpec had a design flaw, but new detectors are now set and ready on all three near-infrared instruments, according to ESA.
"Excellent detectors are crucial to the outstanding instrument performance needed when you want to look at the extremely distant and faint early stars and galaxies that formed when our Universe was still young, and the new detectors secure this top priority of NIRSpec and JWST," said Pierre Ferruit, ESA's JWST project scientist.
A new technology developed for the Webb Space Telescope relates to microshutter arrays. A quarter of a million shutters grouped into four microshutter arrays can analyze light from more than 100 astronomical objects at a time. After testing in 2012, several thousand microshutters were jammed and couldn't open. The cause of the problem was discovered and fixed, according to ESA.
"This required the instrument's outer cover to be opened and therefore an exceptionally strict cleanliness regime was needed to avoid contamination," said Maurice te Plate, ESA's JWST system integration and test manager."In particular, the microshutters are very sensitive to material such as small polyester fibers that can get stuck inside and prevent them from fully closing. We just completed our final checks and we are now ready to install NIRSpec back in to the Module."
"NIRSpec is in its final flight configuration," added Peter Jensen, ESA's JWST project manager. "We have now completed the endeavor we started 11 years ago - it has not been easy, but through skill, persistence, and dedication, the team has made it."
More environmental tests will be run to test JWST's ability to withstand launch and operation before the module is integrated into the observatory for "full-scale cryogenic optical and system testing before launch on an Ariane 5 from Europe's Spaceport in Kourou, French Guiana," ESA wrote.
