Use Cases.pdf

Near Space Network Services Use Case Examples

1.1. Use Cases

The following use cases are provided to help the Contractor understand the various mission profiles they will be expected to support. They should not be considered an exhaustive list of all possible use cases that will be included in a Validation or Operational Services Task Order (TO).

1.1.1. LEO HSF Operations

Human space activities in low Earth orbit involving a long duration facility and the operations necessarily for the human spaceflight mission.

Note: Data transport for "hosted" science payloads or other non-core systems on human spaceflight facilities are similar to data transport needs for LEO robotic missions, so this usage of a facility falls under the Near Earth Robotic LEO Science use case group not the HSF: LEO Ops use case. For example, ISS (data services) would, collectively, be considered a LEO Ultra High use case

• Low Earth orbit

• Data volume varies

• Operations often requires “real-time” (low latency) services (e.g., voice, basic telemetry, video)

• Persistent contact (potentially continuous)

• High availability and reliability of telecommunication services

1.1.2. LEO HSF Operations Servicing

Services for short duration (days to weeks) LEO human spaceflight and cargo re-supply missions servicing LEO HSF platforms with special needs during critical maneuvers (e.g., docking)

• Low Earth orbit

• Ops requires basic services (e.g., voice, basic telemetry) enroute to final destination and periodically while docked

• Data volume < 1 Tb/day

• High reliability of telecommunication services

1.1.3. LEO Science (Low Volume)

Science missions investigating basic phenomena often using a single instrument or low data generation devices; may be small, low-cost platforms

• Low Earth orbit

• Data volume < 100 Gb/day

• Typically no significant latency driver

• Availability & reliability as described in the NSNS SOW

• Basic navigation, location & trajectory User platform constraints (e.g., power, mass limitations)

1.1.4. LEO Science (Moderate Volume)

Science missions using moderate data generation devices or multiple instruments

• Data volume < 1 Tb/day

• Other parameters: Same as Low Volume use case but less platform constraints

1.1.5. LEO Science (High Volume)

Missions using multiple instruments or significant data generation devices such as hyperspectral instruments

• Data volume 1-10 Tb/day

• Other parameters same as Low Volume use case but less platform constraints

• Navigation needs may be more

1.1.6. LEO Science (Ultra-High Volume)

Missions using extremely high volume generation devices (e.g., high resolution synthetic aperture radar

(SAR))

• Data volume very > 10 Tb/day

• Other parameters same as Low Volume use case but no driving platform constraints

• Navigation needs may be more

1.1.7. LEO Weather & Timely Earth Observations

Timely development of weather products has increasingly become a standard service and expectation for many communities, and such needs requires frequent, timely measurements.

• Low Earth sun synchronous or geosynchronous orbit

• Data volume 100 Gb/day to 1-5 Tb/day

• Low latency required (< 95 minutes with goals of < 35 minutes)

• Navigation, location & trajectory as described in the NSNS SOW

1.1.8. GEO Science & Weather

Given the ability to view the same region on Earth, the GEO orbit is valued for variety of science needs especially for weather In addition, simple operations enabled by GEO (e.g., single ground site) make GEO desirable for other types of missions

• Geosynchronous Earth orbit (~35,786 km)

• Data volume typically < 1 Tb/day but may be much greater

• Typically no significant latency driver except weather applications (35-100 min)

1.1.9. HEO Science

Science missions use highly elliptical orbits to conduct science in regions of interest (e.g., magnetosphere) or to get to locations far from Earth.

• Orbits from 100s km (periapsis) to 100,000s km (apoapsis)

• Data volume typically < 500 Gb/day

• Typically no significant latency driver

• Availability & reliability as described in the NSNS SOW

• Basic navigation, location & trajectory

• Mix of platforms many with constraints (e.g., power, mass, spinning spacecraft, multiple mission spacecraft)

1.1.10. Space Weather

Timely warnings of space weather events is increasingly becoming important for energy, telecommunication, and other industries, so “real-time” situation awareness of space weather is an emerging need

• Variety of locations from LEO, highly elliptical, to Lagrange (Sun-Earth L1) and possible future deep space

• Data <100 Gb/day for most critical, low-latency measurements

• Low latency required (minutes)

1.1.11. Science Alert - Persistent Contact

Several types of science measurements that may last a limited time (e.g., gamma ray burst) or work best with coordination are enhanced through persistent contact and timely notification

Though persistent coverage is unlikely from ground stations, this use case includes missions that may request rapid call up from ground stations to download science data.

• Primarily LEO but other locations (e.g., highly elliptical, Lagrange) are possible

• Data <<100 Gb/day for messaging

• Low latency required (seconds/minutes)

1.1.12. Satellite Constellations

Multiple, distributed orbiting platforms are used for Heliophysics and increasingly for Earth Science observation; each platform is essentially a low data volume mission but operated collectively

• LEO or highly-elliptical orbits

• Total data < 1 Tb/day o Each platform typically < 100 Gb/day

• Regular contacts to all platforms, but no significant latency driver

1.1.13. Multi- Region Use Case: Artemis III

To support the Artemis missions, NSN services are required for crewed, uncrewed and robotic assets launching from and returning to Earth, transitioning through cislunar space and operating on the lunar surface.

The Artemis III mission is the first crewed mission to the surface of the moon and includes operations associated with the launch and transport of the crew to cislunar space, descent and landing on the lunar surface, and initial post-landing activities as shown in Figure 7. At this time, NASA expects to operate Lunar Relay services as a demonstration of capability during Artemis III.

Figure 7 Artemis III mission

Table 1 Example NSNS Service Support to Artemis 3 Mission

Astronauts’ Mission Phase NSNS Coverage Launch 1.1 Earth Proximity DTE Transit towards GEO 1.1 Earth Proximity DTE Transit from GEO to NRHO 1.2 Cislunar DTE Operations while in NRHO 1.2 Cislunar DTE, support from 2.2 Cislunar Relay HLS transit from NRHO to Lunar Surface 1.2 Cislunar DTE, support from 2.2 Cislunar Relay HLS surface operations 1.2 Cislunar DTE, support from 2.2 Cislunar Relay

HLS ascent back to NRHO 1.2 Cislunar DTE, support from 2.2 Cislunar Relay Transit from NRHO back towards GEO 1.2 Cislunar DTE Return from GEO to splashdown 1.1 Earth Proximity DTE

Each phase of the Artemis III mission requires NSN communication and navigation services as defined in Table 64.

• Launch, Transit to GEO and Crew Transit to NRHO: This phase begins with the launch of the crew in the Orion vehicle via the Space Launch System (SLS) using trajectory and lunar-gravity assist maneuvers like previous Artemis crew missions. Orion will be inserted into the proper Near- Rectilinear Halo Orbit (NRHO) and then perform a rendezvous with HLS. During this phase, NSN services will include 1.1 Earth Proximity DTE for the launch and transit to GEO and then 1.2 Cislunar DTE for the transit from GEO to NRHO.

• NRHO Operations and Crew/Human Landing System (HLS) transit from NRHO to Lunar Surface: During the stay in cislunar space in NRHO and for the lunar landing, the crew/HLS will need communication and navigation services from both the 1.2 Cislunar DTE and support from

2.2 Cislunar Relay. Driving requirements for this phase are accurate position, navigation and timing services for HLS landing accuracy.

• Surface Operations: On the lunar surface, NSN services are required to provide communication and navigation services for the HLS lander.

• Lunar Ascent and Transit to NRHO: Upon completion of the surface mission, the crew will use the HLS to ascend to Orion. The ascent phase begins at liftoff from the lunar surface and ends with insertion into NRHO. Once the HLS has performed a successful rendezvous and docking with Orion, the crew will transfer to Orion. During this phase, NSN services will include 1.2 Cislunar DTE and 2.2 Cislunar Relay.

• Transit from NRHO to GEO: After the crew performs system checkouts, the lunar surface samples are transferred to and safely stowed in Orion for return to Earth and the crew prepares for NRHO departure. During this phase, NSN services will include 1.2 Cislunar DTE.

• Return from GEO to Splashdown: Orion will utilize a variable duration return trajectory to support Earth entry corridor conditions for water recovery of the crew by the recovery fleet.

During this phase, NSN services will include 1.1 Earth Proximity DTE.

1.1.14. Multi- Region Use Case: Artemis IV

The Artemis IV mission has all of the elements of Artemis III and adds rendezvous with Gateway in NRHO. A graphical summary of the mission parameters is shown in Figure 8. The NSNS service support is identical to the summary shown in Table 64.

Figure 8 Artemis IV mission

Each phase of the Artemis III mission requires NSN communication and navigation services as defined in Table 64. The difference in Artemis V support is to add

• Launch, Transit to GEO and Crew Transit to NRHO: This phase begins with the launch of the crew in the Orion vehicle via the Space Launch System (SLS) using trajectory and lunar-gravity assist maneuvers like previous Artemis crew missions. Orion will be inserted into the proper Near- Rectilinear Halo Orbit (NRHO) and then perform a rendezvous with Gateway. During this phase, NSN services will include 1.1 Earth Proximity DTE for the launch and transit to GEO and then 1.2 Cislunar DTE for the transit from GEO to NRHO.

• Gateway Operations and Crew/Human Landing System (HLS) transit from NRHO to Lunar Surface: During the stay in cislunar space in NRHO and for the lunar landing, the crew/HLS will need communication and navigation services from both the 1.2 Cislunar DTE and support from

2.2 Cislunar Relay. Driving requirements for this phase are accurate position, navigation and timing services for HLS landing accuracy.

• Surface Operations: On the lunar surface, NSN services are required to provide communication and navigation services for the HLS lander.

• Lunar Ascent and Transit to Gateway: Upon completion of the surface mission, the crew will use the HLS to ascend to NRHO. The ascent phase begins at liftoff from the lunar surface and ends with rendezvous with Gateway. Once the HLS has performed a successful rendezvous and docking with Gateway, the crew will transfer to Orion. During this phase, NSN services will include 1.2 Cislunar DTE and 2.2 Cislunar Relay.

• Transit from NRHO to GEO: After the crew performs system checkouts, the lunar surface samples are transferred to and safely stowed in Orion for return to Earth and the crew prepares for Gateway departure. During this phase, NSN services will include 1.2 Cislunar DTE.

• Return from GEO to Splashdown: Orion will utilize a variable duration return trajectory to support Earth entry corridor conditions for water recovery of the crew by the recovery fleet.

During this phase, NSN services will include 1.1 Earth Proximity DTE.

1.1.15. Multi- Region Use Case: Artemis V

The Artemis V mission has all of the elements of Artemis IV and adds elements on the lunar surface. A graphical summary of the mission parameters is shown in Figure 9.

Figure 9 Artemis IV mission

Table 2 Example NSNS Service Support to Artemis Mission

Astronauts’ Mission Phase NSNS Coverage Launch 1.1 Earth Proximity DTE Transit towards GEO 1.1 Earth Proximity DTE Transit from GEO to Gateway 1.2 Cislunar DTE Operations while at Gateway 1.2 Cislunar DTE, support from 2.2 Cislunar Relay HLS transit from Gateway to Lunar Surface 1.2 Cislunar DTE, support from 2.2 Cislunar Relay HLS surface operations 1.2 Cislunar DTE, support from 2.2 Cislunar Relay Surface EVA 2.2 Cislunar Relay HLS ascent back to Gateway 1.2 Cislunar DTE, support from 2.2 Cislunar Relay Transit from Gateway back towards GEO 1.2 Cislunar DTE Return from GEO to splashdown 1.1 Earth Proximity DTE

Each phase of the Artemis III mission requires NSN communication and navigation services as defined in Table 64.

• Launch, Transit to GEO and Crew Transit to the Gateway: This phase begins with the launch of the crew in the Orion vehicle via the Space Launch System (SLS) using trajectory and lunar-gravity assist maneuvers like previous Artemis crew missions. Once Orion is inserted into the proper Near-Rectilinear Halo Orbit (NRHO) and has performed a successful rendezvous with the

Gateway. During this phase, NSN services will include 1.1 Earth Proximity DTE for the launch and transit to GEO and then 1.2 Cislunar DTE for the transit from GEO to Gateway.

• Gateway Operations and Crew/Human Landing System (HLS) transit from Gateway to Lunar Surface: During the stay in cislunar space at Gateway and for the lunar landing, the crew/HLS will need communication and navigation services from both the 1.2 Cislunar DTE and support from 2.2 Cislunar Relay. Driving requirements for this phase are accurate position, navigation and timing services for HLS landing accuracy.

• Surface Operations: On the lunar surface, NSN services are required to provide communication and navigation services for overall exploration activities using assets such as pressurized rovers, EVA suits as well a general habitation as well as accurate position, navigation and timing services for EVA position knowledge and geographical location for science related needs.

• Lunar Ascent and Transit to Gateway: Upon completion of the surface mission, the crew will use the HLS to ascend to Orion/Gateway. The ascent phase begins at liftoff from the lunar surface and ends with insertion into NRHO. Once the HLS has performed a successful rendezvous and docking with the Gateway, the crew will ingress the Gateway. During this phase, NSN services will include 1.2 Cislunar DTE for the lunar ascent and transit to Gateway and support from 2.2 Cislunar Relay.

• Transit from Gateway to GEO: After the crew performs system checkouts, the lunar surface samples are transferred to and safely stowed in Orion for return to Earth and the crew prepares for Gateway departure. During this phase, NSN services will include 1.2 Cislunar DTE for the transit from Gateway to GEO.

• Return from GEO to Splashdown: Prior to the targeted Orion lunar orbit departure time, Orion will undock transit to the NRHO departure burn location. Orion will utilize a variable duration return trajectory to support Earth entry corridor conditions for water recovery of the crew by the recovery fleet. During this phase, NSN services will include 1.1 Earth Proximity DTE.