Chapter 1: Introduction to the Webb Telescope

The James Webb Space Telescope (JWST) has been in development for nearly twenty years, and it is now on the brink of launch. As the most advanced telescope ever constructed, its success depends on the proper deployment of its massive segmented mirror. Recently, NASA achieved a significant milestone by completing the last pre-launch assessment of this crucial component. The next deployment will take place in the vastness of space.

The JWST is designed to be the successor to the aging Hubble Space Telescope, which concluded its last service mission in 2009, coinciding with the end of the Space Shuttle program. Unlike Hubble, which features a single-piece reflector, the JWST utilizes a segmented Korsch-style mirror. This mirror consists of 18 hexagonal segments that create a 6.5-meter reflector. However, due to the 5.4-meter diameter of the Ariane 5 rocket that will carry it to orbit, the mirror must fold for launch.

The mirror is divided into three sections: a central column with 12 segments flanked by two foldable wings, each containing three segments. The optical components are now fully assembled, with thermal shielding secured around the segments—something that was not in place during earlier evaluations. To simulate the conditions in space, NASA employed specialized gravity-offsetting rigs to test the mirror.

The testing team at Northrop Grumman’s facility in Redondo Beach, California, remotely transmitted commands to the telescope, mimicking the signals it will receive while positioned at the Earth-Sun L2 Lagrange point. A failure in the wing deployment could have resulted in further delays for this overdue project. Fortunately, the test concluded successfully, wrapping up the optical assessments.

Chapter 2: Final Preparations Before Launch

After the mirror test, NASA technicians secured the mirrors in their launch configuration. However, additional pre-launch evaluations remain on the agenda. NASA will assess the functionality of two radiators that are crucial for keeping the observatory cool, as well as conduct a full extension and retraction cycle of the deployable tower. This tower plays a vital role by maintaining a distance between the mirror and the warmer sun-facing side of the spacecraft, which is essential for the infrared capabilities of the instruments.

Assuming all final tests yield positive results, the James Webb Space Telescope is slated for launch on October 31, 2021. With the project's cost exceeding $10 billion, its potential to yield groundbreaking discoveries could offer an extraordinary return on investment, particularly if it achieves even a fraction of the success experienced by Hubble.

Now read: NASA Pauses Work on James Webb Space Telescope Due to COVID-19 Pandemic, Engineers Connect Two Halves of NASA’s James Webb Space Telescope for First Time, James Webb Space Telescope Delayed Again to October 31, 2021