Lesson 6 of 6 · Orbital and surface work
Match the suit to orbital or surface work
8 minute lesson · 3 checks along the way
Your goal for this lessonCompare movement, environment and return requirements across different EVA settings.
In this lesson 3 sections · 3 checks
Using archive links & definitions
Words with a dotted underline open a short definition right here in the lesson.
Read & understand
The worksite changes the movement problem
An orbital spacewalk often uses handrails, tethers and restraints to move around and work on a vehicle. A surface adds local weight, walking, terrain and the handling of objects against gravity. The same person and suit face different demands even when both activities occur beyond Earth’s atmosphere.
A surface suit’s lower-body mobility and stability matter for bending, stepping and recovering balance. An orbital worksite may place greater emphasis on controlled translation and stable positioning at a hardware interface. These are general task distinctions, not proof that one suit design performs every job within either category.
Check 1 of 3
10 pointsUse the reading above. You can try again without losing points.
Read & understand
The environment enters the interfaces
Dust on a surface can affect seals, mechanisms, visibility and handling. Surface lighting and thermal conditions can differ sharply between locations and times. A habitat interface must account for what is brought back after an EVA, including equipment and material carried on the suit.
A tool demonstrated on a clean indoor mockup has not necessarily demonstrated repeated operation in a dusty surface environment. The test plan should identify which materials, motion cycles and environmental conditions support the claim. Historical surface experience informs the questions, while new hardware still needs evidence for its own configuration.
Compare the whole EVA
Original teaching diagram. ORBITAL WORK. Translation and body restraint. Vehicle interfaces and tools. SURFACE WORK. Walking, terrain and dust. Habitat return and cleanup. Both need life support and a feasible return; the task and environment set the requirements.
Open full-size diagram in a new tab: Compare the whole EVACheck 2 of 3
10 pointsUse the reading above. You can try again without losing points.
Read & understand
Plan the outward task and the return together
Distance traveled, workload, remaining resources and access to the vehicle or habitat all constrain an EVA. Completing a collection task far from the return point is not the complete mission objective. The plan must preserve a feasible path back under its stated conditions and contingencies.
For a fictional comparison, two routes reach the same worksite. One is shorter but crosses difficult terrain; another is longer with easier movement. Their duration and resource demands cannot be decided from distance alone. Evaluate the actual task, environmental exposure and return capability together. This connects suit engineering with the human-performance and habitat systems in the neighboring courses.
Check 3 of 3
10 pointsUse the reading above. You can try again without losing points.
Put it together
Your lesson progress
Each check connects to a part of the story. Complete all 3 to earn your 25-point lesson bonus.
Explore further · Optional
Go to the source
Explore the evidence behind this lesson. These optional readings and videos open in a new tab.
- Read: NASA: spacesuit engineering and testingCompare the explanation and its assumptions with the worked example in this lesson.
- Read: NASA: spacesuit human-system requirementsCompare the explanation and its assumptions with the worked example in this lesson.
- Read: NASA: Gemini XII and the challenges of spacewalksCompare the explanation and its assumptions with the worked example in this lesson.