The James Webb Space Telescope — a collaboration between NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA) — has successfully completed a critical pre-flight milestone and test that paves the way for continued final testing of the most complex telescope ever built.
At present, James Webb remains on track for a launch from the Guiana Space Centre in Kourou, French Guiana, on an Ariane 5 rocket No Earlier Than 31 October 2021.