The National Polar-orbiting Operational Environmental Satellite System (NPOESS) space segment completed its critical design audit, Northrop Grumman Corp. [NOC] announced.

NPOESS now moves toward critical design review in late April.

In the design audit, in the past year, 85 detailed technical reviews were conducted, with more than 100 customer community reviewers evaluating the depth and maturity of the space segment design elements.

That culminated in the recent 10-day design audit. The space segment consists of the spacecraft bus, science instruments, communication payloads, launch vehicle interface and systems engineering.

NPOESS is the next generation low Earth-orbiting weather and climate monitoring system providing data to civilian and military users through 2025. Northrop is the NPOESS prime contractor.