NASA/TM–2010–216138 

Life Sciences Imp

Lunar Surface Op

Steven P. Chappell1, Jason R. No

1

Wyle Integrated Science and Eng

2

NASA Johnson Space Center, Ho

November 2010 

mplications of

 Operations

Norcross

1

, Andrew F. Abercromby1, Michael L. Ge

Engineering, Houston

 Houston

 Gernhardt2
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NASA/TM–2010–216138 

Life Sciences Imp

Lunar Surface Op

Steven P. Chappell1, Jason R. No

1

Wyle Integrated Science and Eng

2

NASA Johnson Space Center, Ho

November 2010

mplications of

 Operations

Norcross

1

, Andrew F. Abercromby1, Michael L. Ge

Engineering, Houston

 Houston

Gernhardt2
Available from: 

NASA Center for AeroSpace Information National Technical Information Service 

7115 Standard Drive 5285 Port Royal Road 

Hanover, MD 21076-1320 Springfield, VA 22161 

301-621-0390 703-605-6000 

This report is also available in electronic form at http://ston.jsc.nasa.gov/collections/TRS/ 

i 

Table of Contents 

1. Document Purpose and Scope............................................................................................... 1

2. Introduction ............................................................................................................................ 1

2.1. Background ..................................................................................................................... 1

2.2. Lunar Surface Systems ................................................................................................... 2

2.2.1. Space Exploration Vehicle ........................................................................................ 2

2.2.2. Lunar Surface Scenario 12 ........................................................................................ 4

2.3. EVA Testing .................................................................................................................... 5

2.3.1. Integrated Suit Tests ................................................................................................. 6

2.3.2. Exploration Analogs & Mission Development: DRATS 2009 ..................................... 7

3. Methods ................................................................................................................................11

3.1. Crewmember Day-in-the-Life Assumptions .....................................................................11

3.2. Assumptions for Modeling Surface Operations ...............................................................12

4. Results & Discussion ............................................................................................................17

5. Future Work ..........................................................................................................................20

6. Contact .................................................................................................................................20

7. Bibliography ..........................................................................................................................21

Index of Tables 

Table 1 – EVA durations and frequencies during 14-day SEV rover traverse ............................. 7

Table 2 – Assumptions for some typical science and exploration daily activities 

 and their durations ...................................................................................................12

Table 3 – Science and exploration day-in-the-life EVA assumptions .........................................12

Table 4 – Modeling variables and constants .............................................................................13

Table 5 – Crewmember day-in-the-life modeling results ............................................................18

Table 6 – Estimated percentage of days spent performing different types of activities, 

 by mission duration, for scenario 12 ........................................................................19
ii 

Index of Figures 

Figure 1 – Space Exploration Vehicle (SEV) Rover features, 

 including ice-shielded lock for SPE protection ........................................................... 3

Figure 2 – Additional SEV rover features ................................................................................... 4

Figure 3 – Representative scenario 12 complete outpost ........................................................... 5

Figure 4 - Representative planned daily traverse timeline from Desert RATS 2009 

 (Note: headings are in degrees and times are on hours and minutes; 

 TET=traverse elapsed time)...................................................................................... 8

Figure 5 – DRATS 2009 traverse day 5 EVA overview map ....................................................... 9

Figure 6 – DRATS 2009 traverse day 5 EVA detail maps .......................................................... 9

Figure 7 - DRATS 2009 traverse day 5 actual detailed timeline ................................................10

Figure 8 – IST-1 cadence versus speed as a function of gravity level for suited ambulation 

 with suit mass of 121 kg and pressure of 29.6 kPa; scatter plot of all subject data 

 with linear fits for each gravity condition6

 .................................................................14

Figure 9 – IST-1 vertical ground reaction force versus speed as a function of gravity 

 level for suited ambulation with suit mass of 121 kg and pressure of 29.6 kPa; 

 scatter plot of all subject data with linear fits for each gravity condition6

 ..................14

Figure 10 – IST-1 metabolic rate versus speed at different gravity levels during suited 

 locomotion at a constant mass (121 kg) and pressure (29.6 kPa); scatter plot 

 of all subject data with 2nd order fits for each gravity condition6

 ...............................15

Figure 11 – IST-2 metabolic rate for the busy board task at different gravity levels at 

 a constant suit mass (121 kg) and pressure (29.6 kPa); scatter plot of all 

 subject data with 2nd order fit7

 .................................................................................15

Figure 12 – IST-2 metabolic rate for the shoveling task at different gravity levels at 

 a constant suit mass (121 kg) and pressure (29.6 kPa); scatter plot of all 

 subject data with 2nd order fit7

 .................................................................................16

Figure 13 – IST-2 metabolic rate for the rock transfer task at different gravity levels at 

 a constant suit mass (121 kg) and pressure (29.6 kPa); scatter plot of all 

 subject data with 2nd order fit7

 .................................................................................16
iii 
1 

1. Document Purpose and Scope 

The purpose of this report is to document preliminary, predicted, life sciences implications of expected 

operational concepts for lunar surface extravehicular activity (EVA). Algorithms developed through 

simulation and testing in lunar analog environments were used to predict crew metabolic rates and ground 

reaction forces experienced during lunar EVA. Subsequently, the total metabolic energy consumption, 

the daily bone load stimulus, total oxygen needed, and other variables were calculated and provided to 

Human Research Program and Exploration Systems Mission Directorate stakeholders. To provide 

context to the modeling, the report includes an overview of some scenarios that have been considered. 

Concise descriptions of the analog testing and development of the algorithms are also provided. This 

document may be updated to remain current with evolving lunar or other planetary surface operations, 

assumptions and concepts, and to provide additional data and analyses collected during the ongoing 

analog research program. 

2. Introduction 

2.1. Background 

Just over 80 hours of extravehicular activities (EVAs) were performed during the entire Apollo program. 

Scenarios that have been considered by NASA’s Exploration Systems Mission Directorate could involve 

as many as 30,000 hours of lunar exploration EVA time over the span of the program. These plans 

represent a significant increase in EVA hours in an extreme and challenging environment. No previous 

astronaut or spacesuit has performed more than three lunar EVAs, yet under current assumptions future 

astronauts and their EVA suits must be capable of performing more than 600 hours of lunar EVA during a 

6-month mission. Accordingly, it is critical to understand the effect that these mission scenarios will have 

on crew health and performance. 

For example, it is important to understand the metabolic profiles of proposed EVAs to ensure that 

adequate life support, thermal regulation, nutrition, and hydration are available. The amount of 

cardiovascular and resistive exercise provided by EVA should be determined to ensure that exercise 

countermeasures will be adequate to prevent muscle and bone loss and limit overall crew deconditioning 

during long-duration missions. In addition, Apollo astronauts experienced suit-induced trauma to 

fingertips and other areas after only two or three lunar surface EVAs.1 Countermeasures and/or 

operational procedures to limit trauma will therefore be necessary to enable crewmembers to perform the 

high frequency of EVAs envisioned for future missions. 

Other challenges include the risk and consequences of a significant solar particle event (SPE), galactic 

cosmic rays, the need to extend exploration to potentially hundreds of kilometers from an outpost, and the 

increased decompression sickness risk and pre-breathe requirements associated with 55 kPa (8 psi) /32% 

O2 cabin pressure compared to 34.5 kPa (5 psi) /100% O2 in the Apollo Program. Activities being 
2 

conducted in an attempt to address these risks include human testing in pressure chambers under 

controlled, scientific protocols, designed to better understand the risks so that surface systems can be 

designed to mitigate them. Additionally, novel surface systems are being designed to shield astronauts 

from SPEs by making areas of rovers and habitats “safe zones” in which they can wait out events (see 

2.2.1, Space Exploration Vehicle). Also, should astronauts become incapacitated in spacesuits on the 

lunar surface due to system failure, injury, or illness, systems and techniques are being tested in analog 

environments to safely, effectively, and efficiently stabilize and transport them to an area where they can 

be treated and evacuated from the lunar surface.2

2.2. Lunar Surface Systems 

The Lunar Surface Systems (LSS) Project Office was created in August 2007 with the following mission 

statement: 

Develop a sustained human presence on the Moon to promote exploration, science, 

commerce, and the United States’ preeminence in space, and to serve as a stepping 

stone to future exploration of Mars and other destinations. 

The LSS studied several possible lunar surface scenarios with the intent of fulfilling the above mission 

statement. Multiple scenarios were studied that reflected different priorities and technologies that may be 

available. The intent of developing multiple scenarios was to analyze and compare the ability to achieve 

exploration objectives in different ways to enable decision making. To provide context for the following 

discussions, one particular scenario, scenario 12, is described here in some detail. Scenario 12 should 

therefore be considered an example of a possible lunar surface scenario with the understanding that many 

aspects may change. As noted in Section 1, this document may be updated as necessary to reflect 

ongoing changes in the lunar scenarios. 

2.2.1. Space Exploration Vehicle

The Space Exploration Vehicle (SEV) rovers (Figure 1 and Figure 2) are a key component of many of the 

scenarios studied for lunar surface operations. The SEV rovers are intended to optimize human safety and 

performance in planetary exploration by combining a comfortable shirtsleeve, sensor-augmented 

environment for gross translations and geological observations with the ability to rapidly place suited 

astronauts on the planetary surface to take full advantage of human perception, judgement, and dexterity. 

Each SEV rover is slightly larger than the unpressurized Apollo rover. The front cabin of the rover 

provides a pressurized shirtsleeve environment at the same pressure as the habitat or lander. Each SEV 

rover has two suit ports, enabling both rapid egress to the planetary surface and rapid ingress to the shelter 

of the rover in response to solar particle events (SPEs), suit malfunctions, or medical emergencies. A side 

hatch that mates with the habitat, lander, or other SEV rovers enables transfer of personnel and equipment 

under pressure. This capability, along with the capability to quickly step into the suits and perform surface 

operations, results in crewmembers leaving the rover for only the limited portions of an EVA sortie that 
require the superior perception, judg

enable single-person EVA operation

with intravehicular support from a se

rovers also have an EVA driving sta

with all the advantages of an unpress

Because the SEV rovers are capable

limited (8-hour) EVA activities achi

at the end of each day will be avoide

operations. Furthermore, because ea

crewmembers in a contingency retur

range capability than a single larger 

Technology Studies field test demon

productivity of EVA time by an aver

compared with using a UPR vehicle

from an outpost or other location wh

of longer range and lasting up to 14 

(PUP), which incorporates a solar ar

communication equipment. Thus, tra

combinations. 

Figure 1 – Space Exploration

3 

dgement, and dexterity of an astronaut in an EVA suit.

ions wherein one crewmember performs boots-on-surfa

a second crewmember that remains inside the SEV rov

station, enabling them to be operated by a crewmembe

essurized rover (UPR). 

ble of multi-day or week-long sortie durations, rather th

chievable with a UPR, the overhead of returning to the 

ided, and exploration range may be significantly greate

 each SEV rover is a backup to the other and capable o

turn to the base or lander, a system of two SEV rovers 

er pressurized rover. Data from the 2008 Desert Resea

onstrated that this combination of features and capabil

verage of 370% during exploration, mapping, and geol

cle (3).3 The SEV rovers are designed to support 3-day

where power and consumables can be resupplied. To e

14 days, each SEV rover can carry a deployable Portab

 array, additional energy storage, gas and water consum

 traverses up to 14 days are achievable with SEV rover

on Vehicle (SEV) Rover features, including ice

for SPE protection 

uit. It may also 

rface EVA tasks 

over. The SEV 

ber in an EVA suit,

r than the rangehe outpost or lander 

ater than with UPR 

e of supporting four 

s provides greater 

search and 

bilities increased the 

eological operations 

ay traverses away 

o enable traverses 

table Utility Pallet 

sumables, and 

ver and PUP 

ce-shielded lock 
Figure

2.2.2. Lunar Surface Scena

Scenario 12 aimed to develop a fully

missions (landers with crew to utiliz

included in the sequence, building u

total of four SEV rovers were to be 

the initial phase of extended surface

habitat components. There were to b

2024, 2025, and 2026; and four miss

presence was to be achieved in 2027

Pressurized Excursion Module, Pres

the four SEV rovers. These rovers w

but also “private sleep quarters” for 

Fission Surface Power System, exten

to be possible. 

The scenario 12 buildup s

at any time and the loss of

the outpost. The core luna

concepts are applicable no

4 

re 2 – Additional SEV rover features 

nario 12

lly functional polar outpost as early as possible. Sever

ilize whatever surface components were available at the

up to establishment of a lunar base for use in long dur

e delivered on the first two missions. The SEV rovers

ce exploration, serving as mobile bases prior to the dep

be two missions per year in 2022 and 2023; three mis

issions in each successive year after 2026. A continuo

27, at which point the outpost habitation cluster was to

ressurized Core Module, and a Pressurized Logistics M

were to provide not only pressurized roving capabilit

or the crew. Upon delivery in 2028 of a nuclear power 

tended-duration (60 to 90 days) excursions away from

 sequence was designed so that the buildup could

 of any one element would not hinder the functiona

nar surface systems technologies and outpost ope

 not only to lunar exploration, but also to Mars exp

eral lunar sortie 

 the time) were 

duration missions. A 

s were to enable 

deployment of 

missions per year in 

uous human 

s to consist of a 

 Module, along with 

lities for exploration 

er source, the 

om the outpost were 

ld pause 

nality of 

perations 

xploration. 
5 

Figure 3 shows a representative complete scenario 12 outpost. 

Figure 3 – Representative scenario 12 complete outpost 

2.3. EVA Testing 

The EVA Physiology, Systems, & Performance (EPSP) Project utilizes lunar analogs (such as parabolic 

flight aircraft, NASA Extreme Environment Mission Operations [NEEMO], the Neutral Buoyancy 

Laboratory, remote field test sites, and JSC’s Partial Gravity Simulator [POGO] in the Space Vehicle 

Mock-up Facility) to characterize human performance and suit-human interactions during partial-gravity 

EVA. The project is working with the EVA Systems Project Office (ESPO) to develop and execute an 

integrated human testing program across multiple analogs. Along with the EPSP/ESPO tests that are 

providing objective human performance data, the Exploration Analogs and Mission Development 

(EAMD) team is working to evaluate EVA operational concepts that are based on the latest lunar surface 

scenarios. The results from these efforts are integrated to enable informed design decisions, thereby 

ensuring a surface EVA system that optimizes crewmember health, safety, efficiency, and performance. 

 

(2) Power/Support Unit (PSU)

On TRI-ATHLETE

Space Exploration

Vehicles (SEVs) (4)

Sortie

Mode

Lander

Pressurized Core

Module (PCM)

Pressurized

Excursion

Module

(PEM)

Pressurized

Logistics Module (PLM)

Sortie

Airlock

on

Structural

Support

Unit

(SSU)

Portable

Utility

Pallet

(PUP)

w/ Solar

Array (3)

Portable

Comm

Terminal

(PCT)

(2)

Lunar

Surface

Manipulator

System

(LSMS)

(2)

Suit Port Transfer

Module (2)

Stationary O2

Production System (2)

Cargo

Lander

w/

Fission

Surface

Power

System
6 

2.3.1. Integrated Suit Tests

EPSP and ESPO initiated a series of tests collectively referred to as the Integrated Suit Tests in January 

2006 with the EVA Walkback Test (EWT). Following the EWT were Integrated Suit Test 1 (IST-1), 

Integrated Suit Test 2 (IST-2), Integrated Suit Test 3 (IST-3), and the Integrated Parabolic Flight Test. 

EWT, IST-1, IST-2, and IST-3 were performed on POGO, a simulator in the Space Vehicle Mockup 

Facility that utilizes a pneumatic system to offload the weight of suited and unsuited subjects to produce 

partial gravity. The Integrated Parabolic Flight Test utilized the C-9 parabolic flight aircraft provided by 

the Reduced Gravity Office. 

In the EWT, the feasibility of a suited 10-km ambulation was tested to represent a case in which a rover 

(without a second rover available to help) breaks down on the lunar surface and a crew is forced to walk 

back to their habitat or ascent vehicle. The EWT was also performed to determine physiological and 

biomechanical suit parameters (4).4

 The IST-1 objective was to identify the effects of weight, inertial 

mass, pressure, and suit kinematics on the metabolic cost of ambulation in a spacesuit, specifically in the 

MKIII spacesuit technology demonstrator that has a number of features that are expected in future 

spacesuit designs (5).5

 Identifying these effects enabled work toward another objective, to develop 

predictive models of metabolic rate, subjective ratings, and suit kinematics based on measurable suit, task, 

and subject parameters. Similar to IST-1, an objective of IST-2 was to establish the metabolic cost 

associated with changes in weight, inertial mass, pressure, and suit kinematics when performing 

exploration tasks such as shoveling, rock pickup, kneel-and-recover, and light construction tasks. The 

additional data furthered the development of the predictive algorithms initiated by IST-1 (6).6

 Unlike the 

EWT, IST-1, and IST-2, each of which had unsuited and suited components, IST-3 contained only an 

unsuited component because of POGO lift capacity limitations. For IST-3, the direction shifted toward 

exploring the effects of changes in center of gravity on human performance including metabolic rate, 

biomechanics, and subjective measures (7).7

 The Integrated Parabolic Flight Test used the superior 

partial gravity environment of the C-9 aircraft to determine the separate effects of changes in suited 

weight and mass as well as suited center of gravity (8).8

The data gathered from the Integrated Suit Tests will assist in determining how typical EVA work 

correlates with exercise. When the metabolic rates, biomechanics, and subjective measures during EVAlike activities (such as walking and shoveling) are quantified, exercise protocols for long-duration 

missions can be developed that work to supplement the exercise achieved during EVA. 

 
7 

2.3.2. Exploration Analogs & Mission Development: DRATS 2009

The main objective of the 2009 Desert Research and Technology Studies (DRATS) field test was to 

determine the adequacy of the human factors and crew accommodations in an SEV rover to satisfactorily 

support two crewmembers for a 14-day traverse. Along with a number of Lunar Surface Systems 

objectives, EVA frequency and duration estimates were sought by the Human Research Program (HRP) 

for use in models of physiological adaptations during long-duration lunar missions. 

The test was accomplished by planning and executing a 14-day traverse with the prototype SEV rover on 

the Black Point Lava Flow near Flagstaff, Arizona. Productivity, human factors, and performance 

variables were measured according to the study protocol. Detailed timelines were used to plan 

crewmember days during the test, and metrics related to EVAs and other tasks performed were taken. 

Table 1 shows the durations and frequencies of EVAs for the 14-day SEV rover traverse. During the 

science and exploration EVAs, ambulation was performed for contextual observation and geologic 

sampling. When the global positioning system (GPS) data were processed after the test, taking into 

account data losses and accuracy fluctuations, the average distance translated was found to be 416 meters 

per EVA. 

Table 1 – EVA durations and frequencies during 14-day SEV rover traverse 

A representative example of a planned traverse timeline from day 5 of the 14-day mission is shown in 

Figure 4. An overview of the GPS tracks from day 5 EVAs are shown in Figure 5, and Figure 6 shows 

details of each EVA at a finer scale. The blue and red track lines in the figures indicate the positions of 

crewmembers, numbered EV1 and EV2, respectively. Figure 7 shows an example from day 5 of the 

detailed actual timelines that were kept for each day of the traverse. 

The detailed data collected during field tests such as DRATS 2009 and from other analogs serve as a 

critical validation of operations concepts. When field test data are combined with IST data, modeling can 

be performed that provides valuable insight into the life sciences implications of lunar surface operations. 

Avgs.

(h:mm) Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 Day 11 Day 12 Day 13 Day 14

Total EVA Time 1:22 0:21 2:06 1:46 2:20 2:43 0:47 0:56 0:58 2:51 2:18 0:28 1:20 0:25 0:00

EVA Setup, Stowage, & Other 

Time 0:31 0:12 0:31 0:19 0:45 0:33 0:11 0:15 0:17 1:21 0:57 0:23 1:14 0:25 0:00

EVA Translation, Sampling, & 

Contextual Observations Time 0:51 0:09 1:35 1:27 1:35 2:10 0:36 0:41 0:40 1:30 1:21 0:05 0:05 0:00 0:00

Number of Egresses / person / day 2.3 1.0 3.5 3.0 4.0 4.5 1.0 2.0 1.5 4.0 3.5 1.0 2.5 1.0 0.0

Average EVA Duration 0:31 0:21 0:36 0:35 0:35 0:36 0:47 0:28 0:38 0:42 0:39 0:28 0:32 0:25 0:00

14-Day Traverse

(h:mm)
8 

Figure 4 - Representative planned daily traverse timeline from Desert RATS 2009 (Note: 

headings are in degrees and times are in hours and minutes; TET=traverse elapsed time) 

TEAM A

DATE 9/4/2009

DISTANCE LANDMARK HEADING PLANNED TET

1.1 km Edge of Flow 200 0:17 0:17

0:15 0:32

0:45 1:17

0:10 1:27

1.7 km Flow to S 220 0:26 1:53

0:15 2:08

0:45 2:53

0:10 3:03

1.4 km Chanl unit 010 0:21 3:24

0:45 4:09

0:15 4:24

0:20 4:44

0:10 4:54

0.83 km S of Road 010 0:13 5:07

0:05 5:12

0:20 5:32

0:10 5:42

1.0 km Onto knobby 045 0:15 5:57

0:10 6:07

0:30 6:37

0:10 6:47

1.6 km Camp 4 160 0:24 7:11

0:20 7:31

0:59 8:30

0:10 8:40

Max Stay

30

30

30

TET Bingo

Crew A Day 5 Traverse

TIMELINE

Drive to Station 1

EV1/EV2 Egress

Station 1 - Flow Strata

EV1/EV2 Ingress

Drive to Station 2

EV1/EV2 Egress

Station 2 - Flow Edge

EV1/EV2 Ingress

Drive to Station 3

EV1/EV2 Egress

Station 3 - Layered Units

EV1/EV2 Ongress

Drive to Station 4

LUNCH

EV1/EV2 Offgress

Station 4 - Stratified Mesa

EV1/EV2 Ingress

Drive to Station 5

EV1/EV2 Egress

Station 5 - Knobby Unit

Addition Tasks Observations

EV1/EV2 Ingress

Drive to Camp 5

EV2 Egress

PUP Operations

EV2 Ingress

Targets of Opportunity Observations

Xenolith Sample

Unique Lithology Sample

Trench/Core Tube Trench and/or Core
9 

Figure 5 – DRATS 2009 traverse day 5 EVA overview map 

Figure 6 – DRATS 2009 traverse day 5 EVA detail maps 

1200 m EVA 1

EVA 2

EVA 3

EVA 4

50 m EVA 4 50 m EVA 3

50 m

EVA 2 50 m EVA 1
10 

Figure 7 - DRATS 2009 traverse day 5 actual detailed timeline 

TS=troubleshooting Ec=EVA Contextual obs RtE=Rover Translation EVA

Total: In=IV non-productive Es=EVA Sampling RtI=Rover Translation IVA

9:40 En=EV non-productive Et=EVA Translation Rc=contextual obs from Rover

3:22 Eo = EVA setup / cleanup (overhead) Io=IV Overhead

Traverse: 14 Day 5 Geophrase of the Day: 

Cavernous Weathering

EV1 START STOP Δ T (min)

Type 

of 

Work EV2 START STOP Δ T (min)

Type 

of 

Work

Traverse Start 8:00:00 8:00:00 0:00:00 N/A

Egr

es

Egress 

Time

Ingress 

Time Traverse Start 8:00:00 8:00:00 0:00:00 N/A

Eg

re

Egress 

Time

Ingress 

Time

Morning briefing 8:00:00 8:30:00 0:30:00 Io Morning briefing 8:00:00 8:30:00 0:30:00 Io

Holding station, waiting for Go to roll 8:30:00 8:37:00 0:07:00 In Holding station, waiting for Go to roll 8:30:00 8:37:00 0:07:00 In

LER rolling 8:37:00 8:57:00 0:20:00 RtI LER rolling 8:37:00 8:57:00 0:20:00 RtI

stopped for gigapan & geo obs 8:57:00 9:01:00 0:04:00 Rc stopped for gigapan & geo obs 8:57:00 9:01:00 0:04:00 Rc

still making geo obs 9:01:00 9:09:00 0:08:00 Rc still making geo obs 9:01:00 9:09:00 0:08:00 Rc

comms flaky 9:09:00 9:11:00 0:02:00 Ts comms flaky 9:09:00 9:11:00 0:02:00 Ts

comm back 9:11:00 9:11:00 0:00:00 Ts comm back 9:11:00 9:11:00 0:00:00 Ts

conobs 9:11:00 9:17:00 0:06:00 Rc conobs 9:11:00 9:17:00 0:06:00 Rc

Holding station for gigapan 9:17:00 9:21:00 0:04:00 In Holding station for gigapan 9:17:00 9:21:00 0:04:00 In

Driving 9:21:00 9:30:00 0:09:00 RtI conobs 9:21:00 9:30:00 0:09:00 Rc

Holding station for another gigapan 9:30:00 9:35:00 0:05:00 In Hodling station for Gigapan 9:30:00 9:35:00 0:05:00 In

Driving 9:35:00 9:50:00 0:15:00 RtI Conobs 9:35:00 9:50:00 0:15:00 Rc

Holding station for gigapan 9:50:00 9:57:00 0:07:00 In Holding station for gigapan, more cono 9:50:00 9:57:00 0:07:00 In

driving 9:57:00 10:05:00 0:08:00 RtI Driving 9:57:00 10:05:00 0:08:00 RtI

Station 2 EVA parking, egress preparation10:05:00 10:14:00 0:09:00 RtI conobs 10:05:00 10:10:00 0:05:00 Rc

begin egress 10:14:00 10:33:00 0:19:00 Io 1 0:19:00 Station 2 EVA parking, egress prepara10:10:00 10:14:00 0:04:00 Io

Boots on the ground, EVA activities 10:33:00 11:17:00 0:44:00 Es begin egress 10:14:00 10:33:00 0:19:00 Io 1 0:19:00

Ingress procedures 11:17:00 11:23:00 0:06:00 Eo 0:06:00 Boots on the ground, EVA activities 10:33:00 11:17:00 0:44:00 Es

In cabin post-ingress activities 11:23:00 11:27:00 0:04:00 Io Ingress procedures 11:17:00 11:23:00 0:06:00 Eo 0:06:00

Rolling to station 3 11:27:00 11:41:00 0:14:00 RtI In cabin post-ingress activities 11:23:00 11:27:00 0:04:00 Io

Holding for EV2 conobs 11:41:00 11:44:00 0:03:00 Rc Rolling to station 3 11:27:00 11:41:00 0:14:00 RtI

Rolling to station 3 11:44:00 12:08:00 0:24:00 Rc conobs, holding station 11:41:00 11:44:00 0:03:00 Rc

all stop at station 3 12:08:00 12:10:00 0:02:00 Rti Rolling to station 3, conobs 11:44:00 12:08:00 0:24:00 Rc

lunch called 12:10:00 12:30:00 0:20:00 In all stop at station 3 12:08:00 12:10:00 0:02:00 Rc

Egress preparations 12:30:00 12:35:00 0:05:00 Io lunch called 12:10:00 12:30:00 0:20:00 In

begin egress 12:35:00 12:48:00 0:13:00 Io 1 0:13:00 Egress preparations 12:30:00 12:35:00 0:05:00 Io

Boots on the ground, EVA activities 12:48:00 13:06:00 0:18:00 Es begin egress 12:35:00 12:48:00 0:13:00 Io 1 0:13:00

stowing tools, samples 13:06:00 13:06:00 0:00:00 Eo Boots on the ground, EVA activities 12:48:00 13:05:00 0:17:00 Es

begin ingress 13:06:00 13:10:00 0:04:00 Eo 0:04:00 stowing tools, samples 13:05:00 13:07:00 0:02:00 Eo

getting ready to roll 13:10:00 13:18:00 0:08:00 Io ingress procedures 13:07:00 13:11:00 0:04:00 Eo 0:04:00

driving LER to station 4 13:18:00 13:25:00 0:07:00 RtI driving LER to station 4 13:25:00 13:35:00 0:10:00 RtI

LER stopped for gigapan 13:35:00 13:36:00 0:01:00 In LER stopped for gigapan 13:35:00 13:36:00 0:01:00 In

Egress preparations 13:36:00 13:40:00 0:04:00 Io begin egress 13:36:00 13:40:00 0:04:00 Io 1 0:09:00

begin egress 13:40:00 13:45:00 0:05:00 Io 1 0:09:00 egressing 13:40:00 13:45:00 0:05:00 Io

Boots on the ground, EVA activities 13:45:00 14:02:00 0:17:00 Es Boots on the ground, EVA activities 13:45:00 14:02:00 0:17:00 Es

stowing tools, samples 14:02:00 14:07:00 0:05:00 Eo stowing tools, samples 14:02:00 14:07:00 0:05:00 Eo

Ingress procedures 14:07:00 14:10:00 0:03:00 Eo 0:03:00 Ingress procedures 14:07:00 14:11:00 0:04:00 Eo 0:04:00

inside and ready to roll 14:10:00 14:15:00 0:05:00 In inside and ready to roll 14:11:00 14:15:00 0:04:00 In

driving to station 5 14:15:00 14:42:00 0:27:00 RtI LER rolling to station 5 14:15:00 14:40:00 0:25:00 RtI

at station 5 14:42:00 14:42:00 0:00:00 In conobs en route to station 5 14:40:00 14:42:00 0:02:00 Rc

Egress preparations 14:42:00 14:44:00 0:02:00 Io at station 5 14:42:00 14:42:00 0:00:00 In

begin egress 14:44:00 14:51:00 0:07:00 Eo 1 0:07:00 conobs 14:42:00 14:46:00 0:04:00 Rc

Boots on the ground, EVA activities 14:51:00 14:55:00 0:04:00 Es begin egress 14:46:00 14:52:00 0:06:00 Io 1 0:06:00

sampling 14:55:00 15:10:00 0:15:00 Es Boots on the ground, start EVA 14:52:00 14:54:00 0:02:00 Es

ingress prep 15:10:00 15:12:00 0:02:00 Eo conobs 14:54:00 14:55:00 0:01:00 Ec

Ingress procedures 15:12:00 15:15:00 0:03:00 Eo 0:03:00 sampling 14:55:00 15:10:00 0:15:00 Es

inside LER 15:15:00 15:15:00 0:00:00 In ingress preparations 15:09:00 15:10:00 0:01:00 Eo

briefing for PUP docking 15:15:00 15:19:00 0:04:00 Io ingress procedures 15:10:00 15:15:00 0:05:00 Eo 0:05:00

metrics 15:19:00 15:21:00 0:02:00 In inside LER 15:15:00 15:15:00 0:00:00 In

ready to roll 15:21:00 15:25:00 0:04:00 In briefing for PUP docking 15:15:00 15:19:00 0:04:00 Io

LER rolling 15:25:00 15:33:00 0:08:00 RtI ready to roll 15:19:00 15:21:00 0:02:00 In

LER stopped for gigapan 15:33:00 15:37:00 0:04:00 In metrics 15:21:00 15:22:00 0:01:00 In

LER rolling to station 6 15:37:00 16:00:00 0:23:00 RtI ready to roll 15:22:00 15:22:00 0:00:00 In

LER stopped at PUP 16:00:00 16:01:00 0:01:00 In reporting geo obs to SCI 15:22:00 15:25:00 0:03:00 In

tool transfer brief & EVA prep 16:01:00 16:15:00 0:14:00 Io LER rolling 15:25:00 15:33:00 0:08:00 RtI

cabana jam 16:15:00 16:16:00 0:01:00 Ts LER stopped for gigapan 15:33:00 15:37:00 0:04:00 In

waiting for EV2 egress 16:16:00 16:21:00 0:05:00 Rc LER rolling to station 6 15:37:00 16:00:00 0:23:00 RtI

in LER for PUP docking 16:21:00 16:30:00 0:09:00 Rc LER stopped at PUP 16:00:00 16:01:00 0:01:00 In

trash transfer 16:30:00 16:34:00 0:04:00 Io tool transfer brief & EVA prep 16:01:00 16:13:00 0:12:00 Io

EV2 support 16:34:00 16:45:00 0:11:00 Rc begin egress 16:13:00 16:15:00 0:02:00 Io 1 0:10:00

repositioning LER on other side of PUP 16:45:00 16:50:00 0:05:00 RtE cabana jam 16:15:00 16:16:00 0:01:00 Ts

waiting for PUP docking 16:50:00 16:52:00 0:02:00 Rc egress procedures 16:16:00 16:21:00 0:05:00 Io

PUP docking 16:52:00 17:02:00 0:10:00 RtE boots on ground 16:21:00 16:23:00 0:02:00 Et

PUP captured 17:02:00 17:04:00 0:02:00 Rc trash/sample transfer; PUP docking op16:23:00 17:04:00 0:41:00 Et

completing PUP docking procedures 17:04:00 17:06:00 0:02:00 Rc completing PUP docking procedures 17:04:00 17:13:00 0:09:00 Et

standing by 17:06:00 17:22:00 0:16:00 In opening marman 17:13:00 17:18:00 0:05:00 Eo

metrics and debrief 17:22:00 17:28:00 0:06:00 Io ingress preparations 17:18:00 17:20:00 0:02:00 Eo

standing by 17:28:00 17:30:00 0:02:00 In ingress procedures 17:20:00 17:22:00 0:02:00 Eo 0:02:00

debrief with traverse planner 17:30:00 17:33:00 0:03:00 TS inside LER 17:22:00 17:22:00 0:00:00 In

hf forms 17:33:00 17:40:00 0:07:00 TS metrics and debrief 17:22:00 17:28:00 0:06:00 Io

17:40:00 ######## standing by 17:28:00 17:30:00 0:02:00 In

0:00:00 0:00:00 closing cabana, leveling LER 17:30:00 17:33:00 0:03:00 Io

0:00:00 0:00:00 hf forms 17:33:00 17:40:00 0:07:00 Io

Total Time
11 

3. Methods 

Modeling was performed using timelines from DRATS 2009 and a reasonable estimation of a typical dayin-the-life of a crewmember on the lunar surface. Data from field tests were combined with physiological 

and performance data collected, during the Integrated Suit Tests, to project some of the life sciences 

implications associated with these lunar surface operations. A model was developed that takes into 

account such variables as subject mass, suit mass, suit pressure, gravity level, ambulation speed, 

ambulation distance, ground reaction forces, exploration task type, and time spent performing each 

exploration task. The model then outputs information such as metabolic energy consumed, oxygen used, 

water used, and accumulated load. 

3.1. Crewmember Day-in-the-Life Assumptions 

A typical day-in-the-life of a crewmember can be defined that is mostly independent of the lunar surface 

architecture that may eventually be achieved. The data from the 2009 DRATS field test9

 can be 

combined with informed assumptions to allow us to better define this day-in-the-life. 

Table 2 shows assumptions for durations and frequencies of typical daily activities, and Table 3 shows the 

assumptions for EVA-related activities. Table 2 does not provide a detailed minute-by-minute 

breakdown, but rather provides durations and frequencies for required activities. This breakdown is based 

on field-test data from DRATS 2009 and informed assumptions determined by the Exploration Analogs 

& Mission Development (EAMD) team for a science exploration traverse day. 

The maximum duration of a crew work day is assumed to be 900 minutes. Portions of the crew duty day 

not specifically accounted for in Table 2 could be allotted to other activities such as traverses of greater 

distance in the SEV rover, private medical conferences, meals, system checks and maintenance, and 

exercise. In addition, it is worth noting that some activities such as meals or exercise may be performed 

by one crewmember while the other is performing an activity such as driving between stations. 

 
12 

Table 2 – Assumptions for some typical science and exploration daily activities and their 

durations 

Activity 

Duration Activity Frequency 

60 min Post sleep Daily 

15 min Morning planning 

conference Daily 

120 min Pre-EVA (daily) Daily before first EVA 

10 min EVA egress Per EVA 

45 min EVA As needed up to max time 

per day or week 

10 min EVA ingress Per EVA 

20 min Post EVA Daily after last EVA 

15 min Evening planning 

conference Daily 

60 min Pre-sleep Daily 

540 min 

(9 h) Sleep Daily 

Table 3 – Science and exploration day-in-the-life EVA assumptions 

Guideline

A system of SEV rovers will be used for long-distance translation between exploration objectives. 

On average, up to 4 EVAs of 45 min duration each may be performed per day, up to a maximum of 

24 hours / person / week (DRATS 2009 data show that it may be possible to cut this maximum in 

half by doing shorter, more frequent EVAs). 

At each exploration objective, on average 200 m of EVA translation (between objectives at the site) 

may be performed at a higher translation speed and another 100 m of translation (near objectives) 

may occur at a lower translation speed. 

At each site, each crewmember may collect an average of 8 samples, 1/3 of which will be collected 

by hand without the need for tools in 0.5 min, 1/3 of which will require 1 min of hammering, and 1/3 

of which will require 3 min of trenching 

The average mass of samples collected may be 0.3 kg (based on average sample mass from 

DRATS 2009). 

3.2. Assumptions for Modeling Surface Operations 

To estimate the amount of exercise achieved related to EVA, using stated assumptions, data from the ISTs 

and field tests were used to predict the metabolic rate during exploration activities and the daily 

accumulated load (DAL) received from ambulation. For metabolic rates during the different activities, 

measured rates from IST-1 and IST-2 were used and correlated with tasks according to whether the tasks 

were mostly stationary or not and whether they required light or heavy work. A summary and description 

of the variables and constants used in the modeling are given in Table 4. Also, Figure 8 through Figure 

13 are cited here in Table 4. Along with explanations in the “Source/Basis” column, those figures are 

included to further define the sources and bases of the variables and constants used. 
13 

Table 4 – Modeling variables and constants 

Variable / Constant Value Source / Basis

General

Subject mass 80.7 kg Average from IST-1 for 120-kg suit5

Average walking speed 3.0 km/h 

Apollo average of 2.9 km/h11 and lunar 

surface scenarios; DRATS 2009 GPS 

data not used due to data dropouts 

Suit mass 120 kg MKIII Spacesuit Technology 

Demonstrator used in ISTs4 

Water consumption (respiration & 

perspiration) during EVA 240 mL/h NASA Human Systems Integration Requirements, # HS6063 

Total walking distance per day 1.2 km 300 m for each of 4 EVAs based on 

assumptions in Table 3 

Total walking time per day 0.4 h Total distance at average speed defined 

above 

Total EVA time per day 

3.0 h 4 × 45 min EVAs per day based on 

assumptions in 

Table 3

Total IVA time per day 21 h Remainder of day after EVA time per day 

Ground Reaction Force (GRF) 

Foot strikes during ambulation 74/min Average from IST-1 for speeds of 2.3–

3.5 kph5

; also see Figure 8 

Peak vertical ground reaction force 197.1 N Average from IST-1 for speeds of 2.3–

3.5 kph5

; also see Figure 9 

Metabolic Rates

Sitting in pressurized SEV rover 3.9 mL/kg/min 

(91.1 kcal/h) 

Resting metabolic rate based on 

published research10

Walking during EVA 15.4 mL/kg/min 

(359.4 kcal/h) 

Average from IST-1 data for speeds of 

2.3–3.5 km/h5

 at lunar gravity; also see 

Figure 10 

Stationary EVA task – light work (e.g., 

contextual observations, sample 

pickup without tools, setup or stowage 

of equipment) 

13.2 mL/kg/min 

(308.1 kcal/h) 

Average from IST-2 busy board (a light 

construction task)6

 at lunar gravity; also 

see Figure 11 

Stationary EVA task – heavy work 

(e.g., hammering, trenching) 

17.0 mL/kg/min 

(396.8 kcal/h) 

Average from IST-2 shoveling task6 at 

lunar gravity; also see Figure 12 

Mobile EVA task – heavy work (e.g., 

sample transfer to FRED rover) 

18.1 mL/kg/min 

(422.4 kcal/h) 

Average from IST-2 rock transfer task6 at 

lunar gravity; also see Figure 13 

 
14 

Figure 8 – IST-1 cadence versus speed as a function of gravity level for suited 

ambulation with suit mass of 121 kg and pressure of 29.6 kPa; scatter plot of all subject 

data with linear fits for each gravity condition5

 

Figure 9 – IST-1 vertical ground reaction force versus speed as a function of gravity level 

for suited ambulation with suit mass of 121 kg and pressure of 29.6 kPa; scatter plot of 

all subject data with linear fits for each gravity condition5

0

20

40

60

80

100

120

140

160

180

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0

Cadence (steps/min)

Speed (kph)

0.12-g 0.17-g 0.22-g 0.27-g 0.32-g

0

500

1000

1500

2000

2500

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0

Vertical Ground Reaction Force (N)

Speed (kph)

0.12-g 0.17-g 0.22-g 0.27-g 0.32-g
15 

Figure 10 – IST-1 metabolic rate versus speed at different gravity levels during suited 

locomotion at a constant mass (121 kg) and pressure (29.6 kPa); scatter plot of all 

subject data with 2nd order fits for each gravity condition5 

Figure 11 – IST-2 metabolic rate for the “busy board task” at different gravity levels at a constant 

suit mass (121 kg) and pressure (29.6 kPa); scatter plot of all subject data with 2nd order fit6 

0

5

10

15

20

25

30

35

40

45

50

0.0 0.5 1.0 1.5 2.0 2.5 3.0

VO2 (ml·min-1·kg-1)

Speed (m·s-1)

0.12 g 0.17 g 0.22 g 0.27 g 0.32 g

0

5

10

15

20

25

30

35

40

0.10 0.15 0.20 0.25 0.30 0.35

Trial Average VO2 (ml·min-1·kg-1)

Gravity Level (g)

VO2
16 

Figure 12 – IST-2 metabolic rate for the “shoveling task” at different gravity levels at a constant 

suit mass (121 kg) and pressure (29.6 kPa); scatter plot of all subject data with 2nd order fit6

Figure 13 – IST-2 metabolic rate for the “rock transfer task” at different gravity levels at a 

constant suit mass (121 kg) and pressure (29.6 kPa); scatter plot of all subject data with 

2nd order fit6

0

5

10

15

20

25

30

35

40

0.10 0.15 0.20 0.25 0.30 0.35

Trial Average VO2 (ml·min-1·kg-1)

Gravity Level (g)

VO2

0

5

10

15

20

25

30

35

40

0.10 0.15 0.20 0.25 0.30 0.35

Trial Average VO2 (ml·min-1·kg-1)

Gravity Level (g)

VO2
17 

Computation of the total O2 consumption during EVA for the typical day-in-the-life of a crewmember 

was based on the assumption of a constant 4.3-psi suit pressure at 80% O2 for the duration of each EVA. 

The defined typical subject mass of 80.7 kg from IST-1 was used with the metabolic rates in mL/kg/min 

for walking, stationary light work, stationary heavy work, and mobile heavy work to compute kcal/h for 

each type of task. 

The following equation was then used to calculate total kcal used per day during EVA: 

[(Tw × Mw)+ (TLS × MLS) + (THS × MHS) + (THM × MHM)] × number of EVAs per day 

where 

TW = time spent walking during each EVA, in hours 

MW = metabolic rate while walking during each EVA, in kcal/hour 

TLS = time spent on stationary light work during each EVA, in hours 

MLS = metabolic rate during stationary light work during each EVA, in kcal/hour 

THS = time spent on stationary heavy work during each EVA, in hours 

MHS = metabolic rate during stationary heavy work during each EVA, in kcal/hour 

THM = time spent on mobile heavy work during each EVA, in hours 

MHM = metabolic rate during mobile heavy work during each EVA, in kcal/hour 

The energy consumption for each of the subtasks is more simply determined by multiplying the number 

of EVAs per day by the relevant subpart of the equation to obtain the total kcal used per day for that 

subtask. 

The average number of foot strikes during EVA per day was computed by multiplying the assumed 

number of foot strikes per minute from 

Table 4 by the amount of time spent walking during EVA on a typical day. The foot strikes during EVA 

were then combined with the average peak ground reaction force in 

Table 4 using simplified accumulated load calculations (based on the equations in Genc K, et al. The 

Enhanced Daily Load Stimulus (eDLS): Accounting for Saturation, Recovery and Standing. At American 

Society of Biomechanics Annual Conference; 2007; Stanford University.) that accounted for the load 

achieved through walking during EVA: 

TW × (average foot strikes per minute) × [(peak GRF) / (subject mass)] 4 

This simplified equation does not account for the effects and benefits of standing, but it does allow an 

estimation of the accumulated load from EVA. Further modeling with a more complete inclusion of all 

variables that could affect accumulated load was left for future work. 

4. Results & Discussion 

The modeling results presented in this section represent some of the life sciences implications of a typical 

day-in-the-life of a crewmember on the lunar surface performing science and exploration, based on 

testing results from analog environments and the assumptions documented in sections 3.1 and 3.2. 
18 

Table 5 – Crewmember day-in-the-life modeling results 

Variable Modeling Result Basis 

General

Total O2 used per day during EVA 0.05 kg 

From metabolic rates, using data 

from ISTs (3 hours total of EVA 

at a workload breakdown as 

detailed below) 

Total H2O used per day during EVA 0.72 L 

HSIR12 and total EVA time of 3 

hours per EVA assumptions in 

section 3.1 

Metabolic Energy Consumption

Total kcal per day for EVA 1,120 kcal 

Total of all EVA activities, based 

on IST data and categorization 

of activities as detailed below (3 

hours total of EVA per 

assumptions in section 3.1) 

Average kcal per EVA 280 kcal 

Average for each of 4 EVAs 

(based on 0.75 hour EVAs per 

EVA assumptions in section 3.1) 

Average kcal per day from walking 

during EVA 143 kcal 

From EVA walking time without 

samples per day (0.13 hours or 

4.4% of total daily EVA time; per 

EVA assumptions in section 3.1) 

Average kcal per day from 

stationary EVA tasks – light work 

(e.g., contextual observations, 

sample pickup without tools, setup 

& stowage) 

582 kcal 

Based on EVA time not spent 

hammering, trenching, walking, 

or transferring samples per day 

(1.89 hours or 63% of total daily 

EVA time; per EVA assumptions 

in section 3.1) 

Average kcal per day from 

stationary EVA tasks – heavy work 

(e.g., hammering, trenching) 

282 kcal 

Based on EVA hammering & 

trenching time per day (0.71 

hours 23.7% of total daily EVA 

time; per EVA assumptions in 

section 3.1) 

Average kcal per day from mobile 

EVA tasks – heavy work (e.g., 

sample transfer to within site and to 

FRED rover) 

113 kcal 

Based on EVA translation time 

at a site and to SEV rover per 

day (0.27 hours or 8.9% of total 

daily EVA time; per EVA 

assumptions in section 3.1) 

Bone Maintenance

Average number of foot strikes 

during EVA per day (total for all 4 

EVAs in a day) 

4,795 steps 

From time spent walking during 

EVA, average speed, and 

number of foot strikes from ISTs 

Accumulated load per day from 

walking during EVA (total for all 4 

EVAs in a day) 

10,300 kg 

From foot strikes during EVA 

walking and accumulated load 

equations 

The results shown in Table 5 provide estimates of EVA consumables usage, metabolic energy 

consumption, and potential bone maintenance related to loading effects. The consumables usage results 

may be useful for estimating the breathing gas and water that will be needed on an ongoing basis during 

typical EVAs. The computed metabolic energy consumptions offer insight into the exercise achieved and 

nutrition requirements related to EVA for a typical day. The average modeled kcal expended per EVA is 
19 

comparable to the amount computed from Apollo missions, which was about 200 kcal for a 45-minute 

EVA, excluding time spent traversing on the rover (Scott-Pandorf, M., et al., Lunar Explorations During 

Apollo: Velocities and Metabolic Rates. Unpublished NASA paper, 2006). The bone maintenance results 

may be used to estimate the need for measures to counteract bone loss during lunar stays. 

Assumptions based on scenario 12 can be used to define the number of days that may be spent performing 

assembly, maintenance and logistics, and science and exploration for missions of different durations. In 

the buildup sequence, cargo landers that deliver components were alternated with crewed landers to bring 

crewmembers to the lunar surface. The crewed missions were to be of varying durations with a general 

trend toward longer missions. Early missions in the buildup sequence were centered on assembly, and 

many of those missions were to be of shorter duration. As the outpost was built up, mission duration was 

to increase and more time was to be spent on maintenance and on science and exploration. It may be 

assumed that the need for maintenance time increases with the total amount of time that equipment is 

operational on the lunar surface, and a reasonable assumption may be that maintenance time is 5% of the 

cumulative surface time of the outpost. In actuality, maintenance time will be a function of the types of 

components and their frequency of use; this level of modeling may be included in future revisions of this 

report. The assumption for mission days spent on assembly is currently based on a minimum of 1 day to 

be spent on assembly, setup, or checkout for each new component (such as SEV rover or PSU) that is 

delivered to the surface. Again, further modeling may be completed to revise these estimates, if detailed 

timelines can be developed for each type of task. 

Table 6 – Estimated percentage of days spent performing different types of activities, by 

mission duration, for scenario 12 

Mission 

Duration 

(Days) 

Assembly 

Days (%) 

Maintenance 

& Logistics 

Days 

(%) 

Science & 

Exploration 

Days (%) 

7 9% 46% 45% 

14 64% 10% 26% 

28 27% 13% 60% 

45-50 7% 18% 75% 

180 0% 31% 69% 

Note that the activity percentages depend heavily on the 

particular buildup sequence and may vary significantly for 

other scenarios. 

The typical day-in-the-life results apply to the science and exploration days shown in Table 6. The 

percentage of days spent on science and exploration along with the mission duration can be used to get a 

partial look at the results shown in Table 5 across an entire mission. As future work defines assembly, 

maintenance, and logistics tasks, additional modeling can be performed to provide a complete picture of 

the life sciences implications across entire scenarios. 

 
20 

5. Future Work 

Further modeling may be performed as analog testing is completed and as surface operations timelines are 

further developed. EVA timelines for relevant tasks may be included in future revisions of this analysis. 

These may include the following: 

• Assembly tasks 

- Large payload (e.g. SEV, habitat modules) offload from cargo lander 

- Crane deployment and relocation 

- Consumables systems offload from cargo lander, and setup 

- Ladder detachment and relocation 

- Berm building 

• Logistics and maintenance tasks 

- Logistics offload from cargo lander 

- Logistics transfer and utilization 

- Small payload (such as geologic samples) onload and offload from lander 

- SEV rover repair 

- Module maintenance 

- Suit maintenance 

• Science and exploration tasks 

- 1, 3, 7, 14, and 28-day SEV rover science and exploration traverse 

- Sample handling and classification 

6. Contact 

Feedback and questions regarding this report are expected and encouraged, to further the crossdisciplinary collaboration necessary to make informed decisions on future life sciences research as well as 

systems testing and design. Contacts: Steve Chappell, steven.p.chappell@nasa.gov; Andrew Abercromby 

(andrew.f.abercromby@nasa.gov); Jason Norcross (jason.norcross-1@nasa.gov); Mike Gernhardt 

(Michael.l.gernhardt@nasa.gov). 

 
21 

7. Bibliography 

1. Scheuring R, Jones J, Polk J, Gillis D, Schmid J, Duncan J, et al. The Apollo Medical Operations 

Project: Recommendations to Improve Crew Health and Performance for Future Exploration 

Missions and Lunar Surface Operations. Houston: National Aeronautics and Space Administration; 

2007. Report No.: NASA/TM-2007-214755. 

2. Chappell S, Scheuring R, Jones J, Lee P, Comtois J, Hodgson E, et al. Access Systems for Partial 

Gravity Exploration & Rescue: Results from Prototype Testing in an Analog Environment. Chicago: 

37th International Conference on Environmental Systems; 2007. Report No.: 2007-01-3033. 

3. Abercromby A, Gernhardt M. Desert Research and Technology Studies (DRATS) 2008: Evaluation 

of Small Pressurized Rover and Unpressurized Rover Prototype Vehicles in a Lunar Analog 

Environment. Houston: NASA Johnson Space Center; Manuscript submittted for publication. 

4. Norcross J, Lee L, Clowers K, Morency R, Desantis L, De Witt J, et al. Feasibility of Performing a 

Suited 10 km Ambulation on the Moon: Final Report of the EVA Walkback Test (EWT). Houston: 

National Aeronautics and Space Administration; 2009. Report No.: NASA/TP–2009–214796. 

5. Norcross J, Clowers K, Clark T, Harvill L, Morency R, Stroud L, et al. Metabolic Costs and 

Biomechanics of Ambulation in a Planetary Suit. Houston: National Aeronautics and Space 

Administration; 2010. Report No.: NASA/TP-2010-216115. 

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of Gravity on Shirtsleeve Human Performance in Reduced Gravity. Houston: National Aeronautics 

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Gravity, Center of Gravity, & Mass on the Movement Biomechanics, & Operator Compensation of 

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Manuscript submitted for publication. 

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2003 March; Vol. 32: pp. 121-130. 
REPORT DOCUMENTATION PAGE Form Approved 

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 November 2010 NASA Technical Memorandum 

4. TITLE AND SUBTITLE 5. FUNDING NUMBERS

Life Sciences Implications of Lunar Surface Operations 

6. AUTHOR(S) 

Steven P. Chappell, Jason R. Norcross, Andrew F. Abercromby (Wyle Integrated Science 

and Engineering, Houston); 

Michael L. Gernhardt (NASA Johnson Space Center, Houston) 

 

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION 

REPORT NUMBERS

Lyndon B. Johnson Space Center 

Houston, Texas 77058 

S-1084 

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AGENCY REPORT NUMBER

National Aeronautics and Space Administration 

Washington, DC 20546-0001 

TM-2010-216138 

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13. ABSTRACT (Maximum 200 words)

The purpose of this report is to document preliminary, predicted, life sciences implications of expected operational concepts for lunar 

surface extravehicular activity (EVA). Algorithms developed through simulation and testing in lunar analog environments were used 

to predict crew metabolic rates and ground reaction forces experienced during lunar EVA. Subsequently, the total metabolic energy 

consumption, the daily bone load stimulus, total oxygen needed, and other variables were calculated and provided to Human Research 

Program and Exploration Systems Mission Directorate stakeholders. To provide context to the modeling, the report includes an 

overview of some scenarios that have been considered. Concise descriptions of the analog testing and development of the algorithms 

are also provided. This document may be updated to remain current with evolving lunar or other planetary surface operations, 

assumptions and concepts, and to provide additional data and analyses collected during the ongoing analog research program. 

14. SUBJECT TERMS 15. NUMBER OF 

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16. PRICE CODE 

EVA, SEV, exploration, rover, metabolic energy consumption 32 

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