NASAs James Webb Space Telescope. Credit: NASA Goddard Space Flight Center and Northrup Grumman
It has been a long journey for the James Webb Space Telescope, filled with obstacles and challenges to overcome. Some consider its start date all the method back in 1989 when a Next Generation Space Telescope Workshop started looking into a follow-up to the Hubble Space Telescope.
Webb was initially anticipated to launch in 2007, but a series of hold-ups pushed things back until December 25, 2021, when it introduced successfully on an Ariane 5 rocket from Europes Spaceport in French Guiana. Days later it started sunshield release, which was completed effectively on January 4, 2022. The next day it deployed its secondary mirror, and after that on January 8, when its gold-coated, 21-foot main mirror was fully released, Webb had actually concluded all significant spacecraft releases.
After that, it started the long process of mirror positioning, powered on its instruments, kicked off multi-instrument alignment, and proceeded to commissioning the observatorys four powerful science instruments. Capping off these 6 months of releasing, commissioning, and screening, NASA revealed today (July 11) that it is now fully all set for science. Tomorrow (July 12) NASA will launch the first full-color Webb images.
It has been a long journey for the James Webb Space Telescope, filled with challenges and setbacks to overcome. Some consider its start date all the way back in 1989 when a Next Generation Space Telescope Workshop began looking into a follow-up to the Hubble Space Telescope. Things kicked into a higher gear 26 years back, in 1996, with a space telescope design proposition from an 18-member committee led by astronomer Alan Dressler. Each of Webbs 4 major scientific instruments has several modes of operation, using customized lenses, filters, prisms, and specialized equipment that required to be separately checked, adjusted, and eventually verified in their functional configuration in area prior to beginning to catch precise scientific observations of the universe.
Lastly, the months-long process of preparing NASAs James Webb Space Telescope for science is now complete. All of the seventeen methods or modes to run Webbs clinical instruments have now been tested and licensed, which means that Webb has finished its commissioning activities and is prepared to start full clinical operations.
Each of Webbs 4 major clinical instruments has several modes of operation, making use of customized lenses, filters, prisms, and specialized machinery that needed to be individually checked, calibrated, and eventually validated in their functional configuration in area before starting to catch accurate clinical observations of deep space. The last of all seventeen instrument modes to be commissioned was NIRCams coronagraph capability, which works to mostly block incoming starlight by inserting a mask in front of a target star, suppressing the target stars relatively intense light to increase contrast to make it possible for the detection of fainter neighboring companions such as exoplanets. NIRCam, or the Near-Infrared Camera, is geared up with 5 coronagraphic masks– three round masks and 2 bar-shaped masks– that suppress starlight under different conditions of contrast and separation between the star and its buddies.
In addition to capturing comprehensive imagery of deep space, NIRCam is the observatorys primary wavefront sensing unit that is used to tweak the telescopes optics. It has this double responsibility by design due to having a comparatively wide field of vision and possessing a suite of special internal optics that enable it to take out-of-focus images of stars and even take selfie pictures of the primary mirror itself. The group had the ability to start aligning the telescopes optics even while the observatory was still cooling down, since of NIRCams capability to securely run at higher-than-normal, however still cryogenic, running temperature levels.
“From the minute we initially took images with NIRCam to start the telescope alignment procedure to the checkout of coronagraphy at the end of commissioning, NIRCam has carried out perfectly. Observers are going to be very happy with the information they receive, and I am exceptionally pleased with how 20 years of work by my team are now understood in fantastic performance,” stated Marcia Rieke, principal private investigator for the NIRCam instrument and regents professor of astronomy, University of Arizona.
Webbs commissioning procedure culminates tomorrow, July 12, with the release of the telescopes very first spectroscopic data and full-color images, and the authorities beginning of its science mission.