# Cygnus NG-15

> cargo resupply mission to the International Space Station

**Wikidata**: [Q96375776](https://www.wikidata.org/wiki/Q96375776)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Cygnus_NG-15)  
**Source**: https://4ort.xyz/entity/cygnus-ng-15

## Summary
Cygnus NG-15 is an American commercial cargo resupply spacecraft mission to the International Space Station (ISS) flown by Northrop Grumman Space Systems. Launched on 2021-02-20 aboard an Antares rocket, the Cygnus spacecraft (S.S. Katherine Johnson) berthed to the ISS on 2021-02-22 and remained attached until 2021-06-29 before reentering the atmosphere on 2021-07-02.

## Key Facts
- Cygnus NG-15 was launched on 2021-02-20 at 17:36:49 (UTC) from Mid-Atlantic Regional Spaceport Launch Pad 0A.  
- The mission used an Antares launch vehicle.  
- The spacecraft is an instance of the Cygnus Enhanced class and was operated and launched by Northrop Grumman Space Systems.  
- Launch mass (launch weight): 8,050 kilograms.  
- Manifested payload mass delivered to the ISS: 3,734 kilograms.  
- COSPAR ID / NSSDCA ID: 2021-013A.  
- The spacecraft was named S.S. Katherine Johnson (named after Katherine Johnson).  
- The vehicle berthed to the ISS (Unity module, nadir) on 2021-02-22 at 12:16 (UTC).  
- The vehicle unberthed from the ISS (Unity module, nadir) on 2021-06-29 at 16:32 (UTC).  
- Atmospheric entry (deorbit / decay) occurred circa 2021-07-02 at 01:30 (UTC).  
- Manufacturers: Northrop Grumman Space Systems (general contractor) and Thales Alenia Space (subcontractor).  
- Country of origin: United States and Italy.  
- Mission destination: International Space Station (low Earth orbit).  
- Common aliases: S.S. Katherine Johnson; Antares NG-15; NG-15; CRS OA-15; OA-15; Cygnus PCM-15.

## FAQs
### Q: What was Cygnus NG-15?
A: Cygnus NG-15 was a commercial cargo resupply mission to the International Space Station flown by Northrop Grumman using an Enhanced Cygnus spacecraft. It delivered supplies and payloads to the ISS and was designated S.S. Katherine Johnson.

### Q: When was Cygnus NG-15 launched and when did it depart the ISS?
A: Cygnus NG-15 launched on 2021-02-20 (17:36:49 UTC) and berthed to the ISS on 2021-02-22. It unberthed from the ISS on 2021-06-29 and reentered the atmosphere circa 2021-07-02.

### Q: How much mass did Cygnus NG-15 carry and what was its launch mass?
A: The spacecraft had a launch mass of 8,050 kilograms and carried a payload mass of 3,734 kilograms to the ISS.

### Q: Who built and operated Cygnus NG-15?
A: The mission was operated and launched by Northrop Grumman Space Systems. Thales Alenia Space served as a subcontractor to the spacecraft manufacture.

## Why It Matters
Cygnus NG-15 is part of NASA’s Commercial Resupply Services program, which uses commercial providers to deliver cargo, experiments, and hardware to the International Space Station. Missions like NG-15 maintain continuous logistics support for station crews and scientific operations in low Earth orbit without relying solely on government-operated vehicles. NG-15, flown as an Enhanced Cygnus vehicle, carried several tonnes of cargo (3,734 kg) and had a launch mass of 8,050 kg, demonstrating the heavy-lift capability of the Cygnus platform. The mission also continued the partnership between Northrop Grumman (general contractor) and Thales Alenia Space (subcontractor), exemplifying international industrial collaboration (United States and Italy) in commercial spaceflight. The spacecraft’s name, S.S. Katherine Johnson, honors NASA mathematician Katherine Johnson and connects the mission to broader public engagement and recognition of pioneers in space and STEM.

## Notable For
- Named S.S. Katherine Johnson, honoring NASA mathematician Katherine Johnson.  
- Part of the Commercial Resupply Services program providing routine cargo delivery to the ISS.  
- Flew as an Enhanced Cygnus spacecraft with a launch mass of 8,050 kg and delivered 3,734 kg of payload to the ISS.  
- Launched from Mid-Atlantic Regional Spaceport Launch Pad 0A on 2021-02-20 and berthed to the Unity module two days later.  
- Operated by Northrop Grumman Space Systems with Thales Alenia Space as a subcontractor, reflecting U.S.–Italy industrial contribution.

## Body

### Overview
- Mission name: Cygnus NG-15.  
- Instance of: Cygnus Enhanced (uncrewed American cargo spacecraft model).  
- Operator / launch contractor: Northrop Grumman Space Systems.  
- Manufacturers: Northrop Grumman Space Systems (general contractor); Thales Alenia Space (subcontractor).  
- Country of origin: United States and Italy.  
- Aliases: S.S. Katherine Johnson; Antares NG-15; NG-15; CRS OA-15; OA-15; Cygnus PCM-15.

### Launch and Launch Vehicle
- Launch date and time: 2021-02-20 at 17:36:49 (UTC).  
- Launch site: Mid-Atlantic Regional Spaceport Launch Pad 0A.  
- Launch vehicle: Antares.  
- Launch mass: 8,050 kg.

### Mission Timeline and Key Events
- 2021-02-20 — Rocket launch from Mid-Atlantic Regional Spaceport Launch Pad 0A.  
- 2021-02-22 at 12:16 (UTC) — Berthing: Cygnus NG-15 was berthed to the Unity module (nadir) of the International Space Station.  
- 2021-06-29 at 16:32 (UTC) — Unberthing: Cygnus NG-15 unberthed from the Unity module (nadir).  
- 2021-07-02 circa 01:30 (UTC) — Atmospheric entry / orbital decay and mission end.

### Payload and Orbit
- Payload mass delivered to ISS: 3,734 kg.  
- Orbit regime / satellite_of: low Earth orbit (station destination: International Space Station).  
- COSPAR ID and NSSDCA ID: 2021-013A.

### Docking / Berthing Details
- Berthing location: Unity module, nadir.  
- Berthing date/time: 2021-02-22 12:16 (UTC).  
- Unberthing date/time: 2021-06-29 16:32 (UTC).

### Identifiers and Records
- COSPAR ID: 2021-013A.  
- NSSDCA ID: 2021-013A.  
- Google Knowledge Graph ID: /g/11j8_wzbrt.  
- Wikipedia title: Cygnus NG-15.  
- Commons category: Antares NG-15.

## Schema Markup
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  "@context": "https://schema.org",
  "@type": "Thing",
  "name": "Cygnus NG-15",
  "description": "Cygnus NG-15 is a 2021 commercial cargo resupply mission to the International Space Station operated by Northrop Grumman using an Enhanced Cygnus spacecraft named S.S. Katherine Johnson.",
  "sameAs": ["https://en.wikipedia.org/wiki/Cygnus_NG-15"],
  "additionalType": "Cygnus Enhanced"
}

## References

1. Jonathan's Space Report
2. [Source](https://planet4589.org/space/jsr/back/news.795.txt)
3. [Source](https://planet4589.org/space/jsr/back/news.789.txt)
4. [Source](https://blogs.nasa.gov/spacestation/2021/02/22/cygnus-resupply-ship-bolted-to-stations-unity-module/)
5. [Source](https://planet4589.org/space/jsr/back/news.794.txt)
6. [Source](https://spaceflightnow.com/2021/06/29/cygnus-supply-ship-ready-to-end-four-month-mission/)