Postcards from Mars

Analog Astronaut Conference 2025 concludes

Analog Astronaut Conference 2025, Mars yard workshop with Dr. Christopher Hamilton, UA planetary geologist

The Analog Astronaut Conference has enjoyed its fourth year at Biosphere 2. This assembly of artists, writers, innovators, engineers, teachers, researchers, do-it-yourselfers, medical professionals, and yes, people who have made it to the edge of the Earth’s atmosphere and into orbit came together once again to share food, stories, science, and the warmth of direct conversations.

At a time when it seems the world is pushing everyone apart, it is comforting to be in the presence of people from so many countries—Armenia, Germany, Poland, England, Columbia, Argentina, Canada, Mexico, Kenya, the United States and more—to receive the music of accents of a half dozen languages during breakfast, lunch, and dinner. The subject matter of the talks ranged from diversity and inclusion in future human space travel to the science of CO2 scrubbers, from home-grown greenhouse structures built from repurposed water tanks to emotional intelligence as a tool for human interaction in the confines of an isolated habitat.

The SAM staff hosted three workshops:

  • Basics of Wound Care and Suturing by David Wexler, MD and Dr Bindhu Oommen, MD
  • Bioregenerative Life Support with Hydroponics by Atila Meszaros and Luna Powell
  • A Mars Geology Tour by Dr. Christopher Hamilton and Tasha Coelho

The Wound Care workshop was hosted in the SAM Operations Center. The Hydroponics workshop was hosted in the SAM Test Module. And the Mars Geology workshop was hosted in the SAM Mars yard.

In addition, five SAM team members gave expert talks on a wide variety of subject matter:

  • Kai Staats opened the conference with review of the past year at SAM and a look to the future as the SAM team transitions from construction into research for bioregeneration, air revitalization, and advanced medical care for long-duration missions far from Earth.
  • Arizona State School of Earth and Space Exploration Planetary Geology undergraduate and SAM team member Tasha Coelho gave a talk about the current science investigations on Mars.
  • Purdue graduate and new Mechanical Engineer at SAM Griffin Hentzen gave a talk about the new Experimental Air Revitalization Laboratory (EARL) room and carbon dioxide removal system being built at SAM.
  • Bryan Versteeg, world-renowned space architect and member of the SAM team since 2019 gave a talk about his life’s work in helping envision the future of our species as we learn to live in free space and on the surface of the Moon and Mars.
  • Thomas Hoffman of the new Surgical Bay Research Group at SAM (with David Wexler and Bindhu Oommen) gave a talk about the history and current state of aerospace medicine for spaceflight.
By |2025-05-06T06:11:59+00:00May 5th, 2025|Categories: In the news|0 Comments

New SAM Team page

SAM Team montage

Since January 2021 the SAM team has grown from Kai Staats and Trent Tresch and a host of volunteers to an international cadre of staff members who contribute a wealth of knowledge, experience, skills, and motivation to bring to life an advanced research center for human space exploration.

Visit the all-new SAM Team page

By |2025-05-05T18:13:20+00:00April 25th, 2025|Categories: Research & Development|0 Comments

Newly bred compact tomato offers potential for vertical farming

Kai Staats and Changbin Chen in the Test Module of SAM at Biosphere 2

In an era defined by climate volatility and resource scarcity, researchers are developing crops that can survive — and thrive — under pressure.

One such innovation is the newly released tomato variety “Desert Dew” bred by Changbin Chen, associate professor in Arizona State University’s School of Life Sciences. More than just a tomato, Desert Dew represents a leap forward in sustainable agriculture, optimized for rapid growth, nutrient density and adaptability to extreme environments.

Read the full article …

By |2025-04-15T00:13:49+00:00April 14th, 2025|Categories: In the news|0 Comments

SAM IT room gets a coat of paint

The IR room at SAM gets a coat of paint by Matthias and Nathan

The new IT room at SAM is nearly complete. Matthias and Nathan are applying the final coats of paint. We are keeping with the same space-themed colors in the Behr paint product line with “Lunar Surface” and “Mission Control” as applied in the Operations Center, up the hill.

What’s more, we painted the entire south wall of the IT room with chalkboard paint in order that we can hold team meetings in the Mars yard workshop and take notes that everyone can see, leave messages for each other, or simply express a little artistic fun, from time to time.

By |2026-02-15T01:51:07+00:00April 3rd, 2025|Categories: Construction|0 Comments

The 4-bed CO2 scrubber at SAM – Design

Design of a canister stack for the 4-bed CO2 scrubber at SAM, by Griffin Hentzen

by Griffin Hentzen, ME

In any closed environment such as a house, school, or pressure vessel, carbon dioxide (CO2) builds up at a rate dependent on the volume of the space, the number of humans inside, and the degree of closure. With a spacecraft, we will assume complete closure, for our baseline design. After a certain amount of time, the increased CO2 levels can have adverse effects on the crew members. For this reason, all crewed spacecraft have some method of removing CO2 from the cabin air.

Sometimes a single-use system, called a non-regenerable CO2 removal system, is employed. You can find these on short duration spacecraft like SpaceX Crew Dragon or the Boeing Starliner. These systems are simple, but since you can’t regenerate them (remove the CO2 and re-use) on orbit, they are not well suited for long-duration missions.

This is why we are designing a regenerable CO2 removal system for SAM, one that has the capability of capturing (adsorbing) and then releasing (desorbing) CO2 when desired. These systems are in use on the International Space Station (ISS) and are planned for future space stations and long-term crewed missions. SAM will leverage the existing design of the 4-bed-CO2 removal system (4BCO2) currently in use on ISS as the primary CO2 system, under a technology license from NASA Marshall. This will enable SAM crews to remain sealed inside for long duration (multiple week) missions.

I have the honor and priveledge of working with Dr. James Knox, a world leading expert on carbon dioxide removal systems and NASA veteran of nearly three decades. He is working as a consultant with SAM through the University of Arizona.

The 4BCO2 system employs a 4-bed, molecular sieve, thermal-vacuum, swing adsorption cycle. Let’s break that down. 4-bed simply means there are four main metal chambers that hold minerals called desiccants and zeolites. These minerals are very good at capturing water vapor and CO2 at the molecular level (thus, “molecular sieve”). The machine cycles between modes of adsorbing or desorbing (capturing/releasing) water vapor and CO2 based on the temperature and vacuum pressure we apply to them. When the bed is desorbing its CO2, we direct that CO2 down a specific line to permanently separate it from cabin air. Each bed will be adsorbing CO2 or water vapor, and then the cycle will switch, and the bed will “swing” into the other mode. Thus, 4-bed molecular sieve thermal-vacuum swing adsorption cycle.

We have designed or selected most of the essential components at a preliminary level, and are looking forward to seeing how the project progresses. The metal chambers and all flanges are designed by our team and will be manufactured by the University of Arizona’s Welding and Fabrication Facility. Major components such as the valves, blower, heat exchanger and vacuum pump will be Commercial-Off-The-Shelf (COTS) components that meet the required specifications.

Experiment | Design | Components | Assemble | Fabrication | Operation (coming soon)

By |2026-02-18T03:27:02+00:00March 22nd, 2025|Categories: Research & Development|0 Comments

The 4-bed CO2 scrubber at SAM – Experiment

Griffin Hentzen building an early test rig for the 4-bed CO2 scrubber at SAM

Griffin Hentzen building an early test rig for the 4-bed CO2 scrubber at SAM by Griffin Hentzen, ME

As we move into the test phase, we are running a series of tests to ensure that certain custom components will perform as expected. One component of significance is the metal chambers that will hold the desiccant and sorbents. In order to remove a given amount of CO2, the system needs to move a specific volume of air in a given period of time.

An early test rig for the 4-bed CO2 scrubber at SAM by Grffin Hentzen The silica and zeolite beads in the beds cause a significant amount of resistance to that airflow, so it is essential we can calculate the blower capacity for the given, required flowrate. For this immediate test I am repurposing metal chambers and valves used in a previous senior design project (2022), with a new, small blower.

We will measure the pressure drop (the amount of pressure needed to push air through at a given rate) across the metal chamber as well as the flowrate of air. We will control the flowrate by incrementally opening and closing a bleed valve that enables a limited portion of the air to bypass the chamber entirely.

Once we have the correlation between the flowrate and the pressure drop, we will be able to predict the pressure drop in chambers of different sizes and different flowrates. This will allow us to determine the requirements for the final blower we select.

Experiment | Design | Components | Assemble | Fabrication | Operation (coming soon)

By |2026-02-18T03:26:40+00:00March 5th, 2025|Categories: Research & Development|0 Comments

USSF Guardian advances space agriculture research in NASA study

William Wallace at SAM, Biosphere 2

March 3, 2025
by Staff Sgt. Jaime Sanchez
Space Base Delta 1

SCHRIEVER SPACE FORCE BASE, Colo. — In an ongoing NASA study set in the backdrop of Arizona, U.S. Space Force Spc. 4 William Wallace, 4th Space Operations Squadron payload engineer, was invited to further continue the science community’s understanding of extraterrestrial agriculture.

Read the full article …

By |2025-03-04T14:56:41+00:00March 4th, 2025|Categories: In the news|0 Comments

APUS ARG-1S Red Crew Egress

APUS ARG-1S Red Crew exists SAM after five days sealed inside this pressurized facility.

APUS ARG-1S Red Crew Keston Denhalter, Aedanaya Diamond, Gilbert Wilkerson, and Commander Laura Rieske egressed from the SAM research vessel today, February 18, at 10:03 am. They were met in the SAM Mars yard by the members of the Blue Crew and Mission Control.

In the debrief that followed at the SAM Operations Center, the mission was described as a complete success with all science objectives met, data collected on several vital systems (CO2, RH, potable water, hydroponics), and a successful Mode 3 run in which the vessel was fully sealed for four hours.

Photos and narrative coming soon!

By |2025-02-18T21:04:14+00:00February 18th, 2025|Categories: Research Teams|0 Comments
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