Cygnus S.S. Patricia “Patty” Hilliard Robertson (NG-20), the spacecraft used in the mission, undergoing tests at Kennedy Space Center
Mission typeISS logistics
OperatorNorthrop Grumman
COSPAR ID2024-021A Edit this at Wikidata
SATCAT no.58898Edit this on Wikidata
Mission duration113 days, 11 hours and 17 minutes
(in progress)
Spacecraft properties
SpacecraftS.S. Patricia “Patty” Hilliard Robertson
Spacecraft typeEnhanced Cygnus
Start of mission
Launch date30 January 2024, 17:07:15 UTC[1]
RocketFalcon 9 Block 5 ♺, B1077.10
Launch siteCCSFS SLC-40
End of mission
Decay dateJuly 2024 (planned)
Orbital parameters
Reference systemGeocentric orbit
RegimeLow Earth orbit
Berthing at the International Space Station
Berthing portUnity nadir
RMS capture1 February 2024, 09:59 UTC
Berthing date1 February 2024, 12:14 UTC
Time berthed111 days, 16 hours and 10 minutes
(in progress)
Mass3,726 kilograms (8,214 lb)
Pressurised3,712 kilograms (8,184 lb)
Unpressurised14 kilograms (31 lb)

Cygnus NG-20 mission patch  
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NG-20 is the twentieth flight of the Cygnus robotic resupply spacecraft and its seventeenth flight to the International Space Station (ISS). It launched on 30 January 2024.[1][2][3][4] It is contracted to Northrop Grumman under the Commercial Resupply Services II (CRS-2) contract with NASA. The capsule launched aboard a SpaceX Falcon 9 rocket.

Orbital ATK (now Northrop Grumman Space 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 the Cygnus, an advanced spacecraft using a Pressurized Cargo Module (PCM) provided by industrial partner Thales Alenia Space and a Service Module based on the Orbital GEOStar satellite bus.[5]

NG-20 is the first launch of a Cygnus spacecraft after the exhaustion of the supply of Antares rockets, due to the Russian invasion of Ukraine, losing both the Russian rocket engine supplier and the Ukrainian booster stage supplier. The next two Cygnus missions will also use Falcon 9, while subsequent missions will use the next-generation Antares 300 series that is under development, which does not depend on Ukrainian or Russian parts.[6] Cygnus is the only cargo freighter to launch on four different orbital launchers, that is, Antares 100 series, Atlas V, Antares 200 series and Falcon 9 Block 5 rockets.


Cygnus NG-20 is the ninth Cygnus mission under the Commercial Resupply Services-2 contract.

Production and integration of Cygnus spacecraft were 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.[5]


Main article: Cygnus (spacecraft)

The NG-20 spacecraft was named S.S. Patricia "Patty" Hilliard Robertson in memory of astronaut Patricia Robertson.[7] This is the fifteenth flight of the Enhanced-sized Cygnus PCM.[3][8]


The Cygnus spacecraft is loaded with cargo and supplies before its launch.[9]According to the manifest, the Cygnus spacecraft was loaded with up to 3,726 kg (8,214 lb) of cargo.[10][9]


Scientific investigations traveling in the Cygnus spacecraft include tests of a 3D metal printer, semiconductor manufacturing, and thermal protection systems for re-entry to Earth’s atmosphere.[10]

3D Printing in Space

An investigation from ESA (European Space Agency), Metal 3D Printer tests additive manufacturing or 3D printing of small metal parts in microgravity. This investigation provides us with an initial understanding of how such a printer behaves in space. A 3D printer can create many shapes, and we plan to print specimens, first to understand how printing in space may differ from printing on Earth and second to see what types of shapes we can print with this technology. In addition, this activity helps show how crew members can work safely and efficiently with printing metal parts in space.[10]

Results could improve understanding of the functionality, performance, and operations of metal 3D printing in space, as well as the quality, strength, and characteristics of the printed parts. Resupply presents a challenge for future long-duration human missions. Crew members could use 3D printing to create parts for maintenance of equipment on future long-duration spaceflight and on the Moon or Mars, reducing the need to pack spare parts or to predict every tool or object that might be needed, saving time and money at launch.[10]

Advances in metal 3D printing technology also could benefit potential applications on Earth, including manufacturing engines for the automotive, aeronautical, and maritime industries and creating shelters after natural disasters.[10]

Semiconductor Manufacturing in Microgravity

Manufacturing of Semiconductors and Thin-Film Integrated Coatings (MSTIC) examines how microgravity affects thin films that have a wide range of uses. This technology could enable autonomous manufacturing to replace the many machines and processes currently used to make a wide range of semiconductors, potentially leading to the development of more efficient and higher-performing electrical devices.[10]

Manufacturing semiconductor devices in microgravity also may improve their quality and reduce the materials, equipment, and labor required. On future long-duration missions, this technology could provide the capability to produce components and devices in space, reducing the need for resupply missions from Earth. The technology also has applications for devices that harvest energy and provide power on Earth.[10]

Modeling Atmospheric Re-Entry

Scientists who conduct research on the space station often return their experiments to Earth for additional analysis and study. But the conditions that spacecraft experience during atmospheric reentry, including extreme heat, can have unintended effects on their contents. Thermal protection systems used to shield spacecraft and their contents are based on numerical models that often lack validation from actual flight, which can lead to significant overestimates in the size of system needed and take up valuable space and mass. Kentucky Re-entry Probe Experiment-2 (KREPE-2), part of an effort to improve thermal protection system technology, uses five capsules outfitted with different heat shield materials and a variety of sensors to obtain data on actual reentry conditions.[10]

Building on the success of KREPE-1 launched on Cygnus NG-16, improved sensors are added to gather more measurements and improved the communication system to transmit more data. The capsules can be outfitted for other atmospheric re-entry experiments, supporting improvements in heat shielding for applications on Earth, such as protecting people and structures from wildfires.[10]

Remote Robotic Surgery

Robotic Surgery Tech Demo tests the performance of a small robot that can be remotely controlled from Earth to perform surgical procedures. Researchers plan to compare procedures in microgravity and on Earth to evaluate the effects of microgravity and time delays between space and ground.[10]

The robot uses two “hands” to grasp and cut rubber bands, which simulate surgical tissue and provide tension that is used to determine where and how to cut, according to Shane Farritor, chief technology officer at Virtual Incision Corp., developer of the investigation with the University of Nebraska.[10]

Longer space missions increase the likelihood that crew members may need surgical procedures, whether simple stiches or an emergency appendectomy. Results from this investigation could support development of robotic systems to perform these procedures. In addition, the availability of a surgeon in rural areas of the country declined nearly a third between 2001 and 2019. Miniaturization and the ability to remotely control the robot help make surgery available anywhere and anytime on Earth.[10]

NASA has sponsored research on miniature robots for more than 15 years. In 2006, remotely operated robots performed procedures in the underwater NASA’s Extreme Environment Mission Operations (NEEMO) 9 mission. In 2014, a miniature surgical robot performed simulated surgical tasks on the zero-g parabolic airplane.[10]

Growing Cartilage Tissue in Space

Compartment Cartilage Tissue Construct demonstrates two technologies, Janus Base Nano-Matrix and Janus Base Nanopiece. Nano-Matrix is an injectable material that provides a scaffold for formation of cartilage in microgravity, which can serve as a model for studying cartilage diseases. Nanopiece delivers an RNA (ribonucleic acid)-based therapy to combat diseases that cause cartilage degeneration.[10]

Cartilage has a limited ability to self-repair and osteoarthritis is a leading cause of disability in older patients on Earth. Microgravity can trigger cartilage degeneration that mimics the progression of aging-related osteoarthritis but happens more quickly, so research in microgravity could lead to faster development of effective therapies. Results from this investigation could advance cartilage regeneration as a treatment for joint damage and diseases on Earth and contribute to development of ways to maintain cartilage health on future missions to the Moon and Mars.[10]

Launch of Cygnus NG-20


SpaceX launched the Cygnus on 30 January 2024 and docked on 1 February 2024. SpaceX modified their payload fairing for this mission to add a ~5’x4’ door side hatch for late loads of cargo onto the Cygnus spacecraft via mobile cleanroom.[11]

See also


  1. ^ a b Robinson-Smith, Will (30 January 2024). "SpaceX launches Northrop Grumman's Cygnus spacecraft on its way to the Space Station". Spaceflight Now.
  2. ^ Gebhardt, Chris (1 June 2018). "Orbital ATK looks ahead to CRS-2 Cygnus flights, Antares on the commercial market". Retrieved 4 April 2021.
  3. ^ a b Clark, Stephen (1 October 2020). "Northrop Grumman "optimistic" to receive more NASA cargo mission orders". Spaceflight Now. Retrieved 4 April 2021.
  4. ^ "Northrop Grumman shifting to Space Coast for future space station missions". 3 August 2023.
  5. ^ a b "Cygnus Spacecraft". Northrop Grumman. 6 January 2020. Retrieved 4 April 2021.
  6. ^ "Northrop Grumman and Firefly to partner on upgraded Antares". SpaceNews. 2022-08-08. Retrieved 2022-08-09.
  7. ^ Pearlman, Robert (7 December 2023). "Private cargo spacecraft named for shuttle-era astronaut who died of plane crash injuries".
  8. ^ Leone, Dan (17 August 2015). "NASA Orders Two More ISS Cargo Missions From Orbital ATK". SpaceNews. Retrieved 4 April 2021.
  9. ^ a b "Northrop Grumman Commercial Resupply". ISS Program Office. NASA. 1 July 2019. Retrieved 4 April 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  10. ^ a b c d e f g h i j k l m n o "Overview for NASA's Northrop Grumman 20th Commercial Resupply Mission - NASA". 2024-01-25. Retrieved 2024-01-30.
  11. ^ NASA, Northrop Grumman 20th Commercial Resupply Services Mission Prelaunch (Jan. 26, 2024), retrieved 2024-01-31