Welcome to the Mars Simulation Project

The home of the future human settlement on Mars
An Open Source project on GitHub


(Image showing the interconnected modules forming a pressurized environment for living)

The Mars Simulation Project (mars-sim) is an open source Java project aiming at building computer models that characterize operational and relational aspects of establishing human settlements on Mars.

Have you ever been fascinated by reality TV shows in which how contestants face tensions and survive tests? Teamworking is put to test. Driven leaders struggle to exercise self-withstrain by not pitting against those having good solutions in decision-making. Loners learn to step out of self-isolation to collaborate with others to accomplish mutual goals.

(Image from MarsOne)

What mars-sim attempts to model is how early settlers work together to sustain their base. While high-level strategic and mission planning is essential, daily operation of a base falls on how well each individual behaves and relates to one another. Team-working and maintaining good relationship with one another is crucial. mars-sim models each settler with personalities, natural attributes and job skills, and preferences (likes-and-dislikes on a bunch of task). There are tasks to get done in developing and sustaining the settlement. mars-sim defines an assigned role and a job position for each settler with a myriad of tasks to perform. While most tasks are carried out independently by individuals, some require teaming up with others to get done. The social aspect between settlers is modeled by a level of relationship indicator showing how close or how adversarial between any two individuals.

With private ventures such as SpaceX offering new vision of going to Mars and the Mars One Foundation seeking to recruit future settlers on a one-way ticket to Mars, mars-sim is giving the audience a preview of the coming attractions in unraveling the intricate innerworking of establishing a human foothold on Mars.

Your Face Here
(Image credit: Mashable.com, 2013)

The good news is that, unlike in a TV soap opera in that the relationship dynamics of the characters are scripted to appeal to a qualified audience, actions and reactions of each settler in mars-sim are emergent. They interact with one anotherunder certain mission requirements and environmental stressors as the settlement is being developed. Their personality and natural attributes can positively or negatively affect social networking. Just like in real life, the bond between any two individuals gets strengthened with positive feedback and worsen with negative exchange, or degraded over time when less contact is made.

(Cutaway of a proposed 4-person Habitat Module. Image: Ian Warpole, Scientific American)

Below are the type of questions you may ask yourself if you are a mission planner for a human-rated Mars mission:

(a). What types of psychological profile of the team should I select for each mission going to Mars to jump-start a colony vs. sustain the settlement?

(b). How many of them should I send on each mission, accompanied with what resources, parts, equipment, vehicles, and building modules?

(c). How often should I send these resupply missions to seed each existing settlement or to start a new outpost nearby?

(d). What interventions do I need to do to ensure these settlers balance between their own personal needs and the collective needs? In mars-sim, you will have an opportunity to flesh out your own ideas and hypotheses in how a settlement should be run and how mission planning is done.

(Image from Outerplaces.com and Mars-One.com )


Screenshots from Mars Simulation Project Version 3.1.0

Settlement Map and Mars Navigator Mini-map
Mining Outpost
Monitor Tool
Help Browser
Info Windows: Vehicle/Settlement/Bots
Info Window: Person


Robert Zubrin once proposed four phases in the economics of Mars colonization. Each represents a new progressive stage of increased human activities toward building a human civilization on Mars.

(Image based on Mars Direct, Robert Zubrin, The Mars Society)

(1). EXPLORATION : Orbital survey of Mars, telescopic and robotic survey, precursor sample return, scientific investigations, human flyby/EVA/landing/return;

(How soon before humans trek across the landscape of Mars? Artist's concept depicts crew members involved in sample analysis on Mars. Image from NASA)

(2). BASE BUILDING : Semi-permanent laboratory/habitat modules, crew rotations, water/ice recovery, in-situ fuel production, outpost maintenance/sustainment;

(Cutout of a Multi-purpose Habitat. Image from MarsOne)

(3). SETTLEMENT : Colony expansion, food and resources supply chain, terrestrial exploitation, economic viability, industrial production, infrastructure redundancy;

(Mars Under Construction. Image: Bryan Versteeg/Spacehabs.com)

(4). TERRAFORMING : Altering global climate, large scale geo-engineering, permanently transforming human surface activities.

Currently, mars-sim focuses primarily in offering a simulation engine showcasing human activities in the aforementioned phase 1 and some phase 2 and a little bit of phase 3. Below are the five core features of mars-sim:

(Terraforming Mars is not for faint of heart. Image credit: Stefan Morrell. Sources: Christopher McKay, NASA Ames Research Center; James Graham, University of Wisconsin–Madison; Robert Zubrin, Mars Society; Margarita Marinova, California Institute of Technology)

(I). Mission Scenarios

mars-sim borrows from a variant form of the Mars Direct plan proposed by Zubrin and Baker in 1990s. Select 'New Sim' in the Main Menu will take you to the Simulation Configuration Editor. By default, you are presented with two settlements, namely a Mars Direct Base (Phase 1) with 4 settlers and an Alpha Base (Phase 4) with 24 settlers. You are free to reconfigure this template.

In version 3.1.0, users may designate a space agency to sponsor each settlement. The names of the settler will be auto-generated to suit his/her national origin, based on the space agency chosen.

In terms of resupply mission, for a Mars Direct Base Phase 1, the built-in resupply schedule will send one new mission each Martian year (668 or 669 sols) for the next 3 years to replenish existing settlements. Using Resupply Tool, users can tweak the launch/arrival date, the number of settlers and the type/ quantity of supplies (including buildings, equipment, vehicles, resources, and parts).

Simulation Configuration Editor
(Image from the Simulation Configuration Editor)

Crew Editor
(Image from the Crew Editor)

(II). Profile of Settlers

Each settler is assigned with a Job which will determine a list of relevant tasks and missions at a given Work Shift. There are a variety of Job in mars-sim: Architect, Areologist, Astronomer, Biologist, Botanist, Chef, Chemist, Doctor, Driver, Engineer, Manager, Mathematician, Meterologist, Physicist, Technician, and Trader. Users can change a person's Job in the Activity Tab.

In version 3.1.0, each settlement will have a leadership structure. For a settlement with less than 47 settlers, the hierachy comprises a commander, and sub-commander and a list of chiefs and a list of specialists. FOr a settlement with 48 people, a mayor will be elected. Each settler will have a given Role based on his/her natural attributes and skills. The roles are not fixed and can change over time.

A person's Skills Tab will show his current level of achievement on each skill subject. Each individual has a blend of academic skills (such as Aerology, Astronomy, Biology, Chemistry, Mathematics, Meteorology, Physics, etc.) and survival skills (such as Botany, Cooking, Construction, Driving, EVA Operations, Material Science, Mechanics, Medicine, Trading, etc.) that will contribute to the survival and sustainment of the settlement. When a settler takes up the role of a chef, the corresponding skill--namely cooking-- will improve. The one whose skill is higher level may mentor one whose skill is lower. Over time, settlers may cross train among themselves to improve skills or acquire new skills. With overlapping skills, settlers depend on one another to get through disasters and catastrophes.

Settlers perform tasks and activities according to their personal needs and the collective needs of the settlement. There are a myriad of tasks such as Growing crops, Sleeping, Cooking, Relaxing, Exercising, Doing Yoga, Eating a Meal, Performing Maintenance, Performing Experiments, Manufacturing, Tending Greenhouse, Entering/Exiting EVA, Driving Vehicle, Collecting Resources, Perform Study, and Teaching, etc.. Some tasks are more career-oriented than others. As you can imagine, chefs prepare meals, botanists tend greenhouses, technicians perform maintenance, engineers manufacture needed parts and equipment from local resources, etc..

Settlers also form tag teams to explore treacherous terrains, prospect rock samples and mine minerals. Based on supply and demand, they will set out excursions to trade with neighboring settlements as there are hundreds of items called "Trade Goods". Some of these items may be in surplus on one settlement but are in wants by another settlement. On the other hand, some settlers may have overwhelming scientific ambitions to just stay put and write proposals and conduct scientific study. Their goals would be earning Scientific Achievement Credits. As the primary researchers, they recruit collaborators on their projects. Without a doubt, settlers of Mars are pioneers of the next human frontier.

(A Mars Expedition. Image credit: Douglas Shrock- the Artist Shrox)

(III). Health and Radiation Modeling

mars-sim simulates realistic scenarios in which settler will cope with accidents of all kinds, illnesses, injuries and even death. Each settler has 4 critical health attributes reflecting the person's current physical conditions: Hunger, Fatigue, Stress and Performance level. A person's overall health status may be reported as being well or being sick (such as Suffocating, Recovering from Anxiety Attack/Flu/Pulled Muscle, and Death, etc..)

In version 3.1.0, a radiation exposure modeling based on NASA's studies has been partially implemented to make it realistic. There are 3 possible type of radiation events : (A). The Baseline (B).the Galactic Cosmic Radiation (GCR) (C). Solar Energetic Event (SEP). Each with different level of radiation with SEP the highest level of exposure. The 3 body regions where the exposure are to be tracked are (1) Blood Forming Organ (BFO) (2) Ocular (3) Skin. In our modeling, there are 3 intervals (or counters) for the exposure: (1) 30 days (2) Annual (3) Career. e.g. for BFO, the max limits are set to be 250 mSV for 30 days, 500 mSV for Annual and 1000 mSV for Career.

As a side note here, the Mars rover Curiosity received an average dose of 300 milli-sieverts (mSv) over the 180-day journey. Note that 300 mSv is equivalent to 24 CAT scans, or more than 15x the annual radiation limit for a worker in a nuclear power plant.

One must be reminded that in the forseeable future, Mars is a by-and-large dangerous and unforgiving world. Survival hinges upon how well each settler responds to situations and how well they pull together as a team. Equipment can malfunction and building break down and require maintenance. There are times when one has to go out on a rescue mission to tow a stranded vehicle back to the base.

(Working Inside Greenhouse. Image credit: Douglas Shrock- the Artist Shrox)

(IV). Social/Professional Interactions and Achievements

mars-sim simulates the overall professional relationship for the future settlers on Mars. Each settler bears an imprint of one's gender, date of birth, weight, height, BMI, age, blood type, a personality profile based on Myers-Briggs Type Indicators (MBTI) and Five Factor Model (FFM), and a set of natural attributes (such as Agility, Academic Aptitude, Attractiveness, Conversation, Endurance, Experience Aptitude, Leadership, Strength, Stress Resilience, and Teaching). These characteristics set in motion on how well a person interact with his/her team and others socially and professionally.

One can track how a person relate with another with the Relationship Tab. Suffice to say that each settler with one's personality types, coupling with his unique set of natural attributes and professional skills, create the destiny of his/her own.

A person's Science Tab lists the ongoing and finished scientific studies with others and the scientific achievement in his/her areas of endeavour.

Your Face Here
(Image credit: pioneer-city.com)

(V). Interconnectiveness

The Settlement Map provides each settlement a visual overview of the whereabout of each building, settler, bot and vehicle. You can see how buildings are seamlessly interconnected via hallways or tunnels. The Settlement Info Window provides clues on how well each system is functioning behind the scene. No two settlements are alike. You can make each settlement unique by having distinguishable mission footprints and infrastructures and by ways of how settlers behaves.

Beginning version 3.1.0, each settlement has an objective-- the overall development objective that certain activities such as manufacturing and food production processes tend to gear toward.

The 6 possible objectives :
(1). Crop Farm
(2). Manufacturing
(3). Research Center
(4). Transportation Hub
(5). Trade Town
(6). Tourism

(2-D blueprint of a Mars outpost with connected modules. Image courtesy of Georgi Petrov and Mars Foundation.)

As settlements grow and more buildings are shipped in or being constructed on site according to the needs, a diversity of specialty functions would result. It's not difficult to imagine a settlement become an university town housing numerous laboratories attracting academically driven settlers if it heavily sponsors research studies on those disciplines. A green town may be developed to house a large number of interonnected greenhouses having a company of biologists/botanists experimenting with improving crop rotations and genetics that give better crop yield. A maker-haven is one that consists of a lot of workshops with machineries providing high industrial throughput and attracting influx of creative individuals to prototype and tinker with tools to produce new parts and equipment. Also, with more prospectors arriving on Mars, mining outposts will be the next frontier and they will sprout up everywhere along a resource-rich basin/region, fortifying the local supply chain for raw minerals.


mars-sim v3.6.2 is available for free in 4 binary editions (most of us run the Swing Jar Edition). Download the latest build or release today at:

A. Sourceforge's auto-download

Download Mars Simulation Project

B. Sourceforge's manual download

C. GitHub

release tab

D. Previous Releases

Also, you may download this previous v3.06 User Guide as a reference.

Minimum Requirements :

a. Dual Core Pentium/Celeron 1.5 GHz or above
b. 2 GB free RAM dedicated for running mars-sim
c. 64-bit Oracle Java 17 or OpenJDK 17


For more details on mars-sim development, go to GitHub project page.

Also, check out openhub for a summary of mars-sim development.


We would like to invite you to discuss mars-sim and topics relating to human settlement on Mars in our facebook group. Please click the button below.