Uploaded June 2014 | Updated September 2026, 10 hours ago

---

Engineers held their breath. The "heart" of the James Webb Space Telescope hung from a cable 30 feet in the air as it was lowered slowly into the massive thermal vacuum chamber at NASA's Goddard Space Flight Center.

SOURCE: NASA's Goddard Space Flight Center

Read more: laboratoryequipment.com/videos/2014/06/webbs-heart-lowered-test-chamber