[3] It travels in a polar orbit, crossing the equator approximately 14 times a daily, and provides complete global coverage twice a day.

[4] NOAA-21 ensures the continuity of satellite-based observations and products for NOAA's Polar-Orbiting Environmental Satellites (POES) and Suomi NPP systems.

[5] On 24 March 2015, NASA announced that Orbital ATK would build one, and possibly three, Joint Polar Satellite System spacecraft.

The second Ice, Cloud and Land Elevation satellite (ICESat-2) and the Landsat 9 spacecraft are also based on the LEOStar-3 and are being built at Orbital ATK's Gilbert facility at the same time.

[14] The Cross-track Infrared Sounder (CrIS) instrument will be used to produce high-resolution, three-dimensional moisture, pressure, and temperature profiles.

Better testing and monitoring of the complex chemistry involved in ozone destruction near the troposphere is made possible by the improved vertical resolution of OMPS data products.

Because of these challenges, and the low risk of experiencing a gap in this data record due to having two relatively new instruments in orbit at the time, NASA decided to discontinue development of RBI.

After moving the instrument to NOAA-21 and awarding the contract for development in June 2014,[19] NASA almost immediately began the process of dropping the sensor.

[22] But on 26 January 2018, NASA announced their intention to discontinue development of RBI and shortly thereafter it was again left unfunded in the Trump administration's FY 2019 budget.