Cygnus NG-15

Cygnus NG-15, previously known as OA-15, was the fifteenth launch of the Northrop Grumman robotic resupply spacecraft Cygnus and its fourteenth flight to the International Space Station (ISS) under the Commercial Resupply Services (CRS) contract with NASA. The mission launched on 20 February 2021 at 17:36:50 UTC. This is the fourth launch of Cygnus under the CRS-2 contract.

Orbital ATK (now Northrop Grumman Innovation Systems) and NASA jointly developed a new space transportation system to provide commercial cargo resupply services to the International Space Station (ISS). Under the Commercial Orbital Transportation Services (COTS) program, Orbital ATK designed, acquired, built, and assembled these components: Antares, a medium-class launch vehicle; Cygnus, an advanced spacecraft using a Pressurized Cargo Module (PCM) provided by industrial partner Thales Alenia Space of Turin, Italy, and a Service Module based on the Orbital GEOStar satellite bus.

NASA held a pre-launch briefing for the Northrop Grumman Cygnus NG-15 cargo launch to the International Space Station (ISS) on 19 February 2021 at 16:00 UTC. Late cargo loading concluded on 19 February 2021. The Cygnus NG-15 spacecraft launched the next day at 17:36:50 UTC on an Antares launch vehicle from the Mid-Atlantic Regional Spaceport (MARS) at NASA's Wallops Flight Facility, Wallops Island, Virginia. Cygnus NG-15 is the fourth Cygnus mission under the Commercial Resupply Services-2 contract. Production and integration of Cygnus spacecraft are performed in Dulles, Virginia. The Cygnus service module is mated with the pressurized cargo module at the launch site, and mission operations are conducted from control centers in Dulles, Virginia and Houston, Texas.

This was the tenth flight of the Enhanced-sized Cygnus PCM (Pressurized Cargo Module). On 1 February 2021, the start of Black History Month, Northrop Grumman announced the name of Katherine Johnson, NASA mathematician, as the name of the Cygnus spacecraft.

Once its mission has been completed, Cygnus will perform a safe, destructive reentry into atmosphere of Earth over the Pacific Ocean.

The Cygnus spacecraft was loaded with 3,810 kg (8,400 lb) of research, hardware, and crew supplies. This was the heaviest CRS cargo launch NASA made to ISS at the time. The cargo manifest is broken down as follows:

NASA provided the following breakdown of the cargo's hardware for ISS:

The new experiments arriving at the orbiting laboratory on the Cygnus NG-15 mission supports science from human health to high-powered computing, and utilizes the space station as a proving ground for the technologies needed for future missions to the Moon and on to Mars.