Research & Development

The SAM team continues to work non-stop to cross-off a massive list of tasks and action items, while juggling a growing array of visiting researchers, artists, and film crews.

When SAM was getting going, those first few years (2021-2023), Director of Research Kai Staats wrote a weekly summary of the tasks completed and those tasks that remained. This was delivered to the working group via a managed email list. Those items relevant to the work on-site were (and are still today) translated to a blackboard such that each team member is immediately aware of the full scope of projects and priorities for each day. What’s more, when a task is complete, the gratification of crossing it off the list is immediate and well received.

“In the context of so many available software programs for project management, I have found, through more than thirty years project management, that software can cause as many problems as it solves, and generally requires a dedicated manager, as asking each engineer to login and check off items is a waste of their time, not what they want to do, and usually never gets done.

Blackboards, however, require no power or recharging. They can hold a message for hours, days, or weeks without screen burn. And they engage team members in a kinesthetic function, walking, picking up chalk or chalk pens, and moving the entire upper body, not just typing on a two-dimensional screen.

Finally, and this one is difficult to formalize, there are some team members who are adept at the artistic side of communication, and truly enjoy the effort (ie. Luna). The rest of us smile with each refresh of the blackboard through the creative application of color, context, and style.

As such email-to-blackboard is not for everyone, but if you haven’t tried it, maybe you should!

And now, an edited version of my email to the team, sent earlier today …

Greetings SAM Working Group,

*** SCIENCE OBJECTIVES 2026 ***

The #1 objective of 2026 is also the very reason SAM was built—to demonstrate a hybrid bioregenerative / physico-chemical crewed mission in SAM. In the month of November we will host one or two crew members (TBD) for 30 days. The exact design of this mission will be crafted over this summer and fall, determining if we grow the plants to maturity during the mission, or as we did last October start the mission with mature plants and then harvest mid-mission, then relying on the CO2 scrubber running in EARL. There is also a three-phase approach, which mixes things up a bit.

Luna has this week received seeds for the next set of food cultivar experiments and will on Monday work with Jason to plant them in the incubator at Biosphere 2. In two weeks we’ll transplant the seedlings into the TM for 5-6 weeks growth (depending on the species). Luna will provide the plant schedule by the close of this week.

[skipping a half dozen sections]

*** PROJECTS COMPLETED ***

Here are a few tasks completed from the past month or so:
– replace Mars yard west wall panels – DONE
– fix gutters, paint south wall panels – DONE
– pour floor epoxy in EARL – DONE
– install EARL mini-split A/C – DONE
– finish EARL external paneling – DONE
– finish MedBay fabrication – DONE (for now)
– lung patches reinstalled – DONE
– replace lower lung door seal – DONE
– clean upper and lower lung – DONE
– cover Lung with tarp until sealed – DONE

*** PROJECT TODOs ***

SAM AIR
– install air line from EARL
– sheetrock and paint south wall and ceiling

SAM Lung
– repair foam over lung
– further test lower lung door for leaks
– final paint coat of upper lung pan

SAM Test Module
– install new water pumps (see prior email)
– find a way to seal the primary door more easily
– check for / seal any leaks
– test new seal(s) for TM/EB hatch
– fabricate bulkhead pass-through for water, fire detector
– replace potable water tank with stainless steel for Aug team

SAM Engineering Bay
– learn if the floor is a major leak point; and rebuild if necessary
– fabricate bulkhead pass-through for water, fire detector

SAM Crew Quarters
– learn if the floor is a major leak point; and rebuild if necessary
– build recycling shower for August team
– build sleeping pods from 80/20 for August team
– finish MedBay: install bed clip, surgical tools
– apply silicone to exterior roof (?)

SAM EARL and Scrubber
– install door sweep and threshold
– install LCD screen on north wall; install scrubber control computer
– rebuild stacks with new check valve, seal
– replace DC data cables with insulated, twisted pair
– resolve RMI issues that cancel data transmission
– drain chlorinated water; replace with straight water
– install water line cover to reduce algae build-up

And most important of all, tie the SAM Crew Quarters into EARL and the scrubber. This is a BIG project, and will surely take several days, if not two weeks. Matthias and I have explored some ideas, simplifying the effort—we’ll share more once the ideas are solidified.

SAM MedBay
– order surgical tools and supplies
– build 3D computer model
– invite external team members to participate in a mock, medical mission

SAM OPS
– install exterior and interior door (2) trim
– install workshop chem table
– purchase and install cabinets
– hang new artwork in the conference room and den
– install aluminum “T” in slot between countertop sections
– finish kitchen (stove top, microwave, pots & pans)
– replace facia (2×4) along exterior, south edge of roof

Well, that’s it! No more than at any other time in the past five years, but not less. Yet somehow, as we bring Development Phase V to close, it feels good to see all we have accomplished since January 20, 2021.

Cheers,
kai

With the close of January, mechanical engineer Griffin Hentzen concluded his one-year work at SAM to design and build the 4-bed CO2 scrubber, licensed from NASA and a work-alike for the scrubber operating on the International Space Station.

University of Arizona undergraduate students Alyssa Ackerman, Brendon Phoebe, and Jeff Buskirk trained under Griffin for the final two months of 2025 and the full month of January. With Griffin’s departure, Director of Research Kai Staats and team member Matthias Beach joined Alyssa, Brendon, and Jeff in a review of the total system.

As it was assembled quickly prior to Griffin’s departure, to demonstrate a first-order function. In review of both the A/C wiring for the chamber heaters, and the D/C wiring for the sensors, it was determined best to rewire the entire scrubber. This effort was guided by Kai, and executed by Matthias and our UA student team, for roughly two weeks. We completed the rewire and immediately dove into a full run of the 4-bed CO2 scrubber for our second paper for the International Conference on Environmental Systems.

This experiment was 4-fold:

1. Demonstrate the effective leak rate of the room
2. Demonstrate the CO2 generated by one team member sealed inside
3. Demonstrate the adsorb (capture) function of the CO2 scrubber
4. Demonstrate the desorb (release) function of the CO2 scrubber

While the Experimental Air Revitalization Laboratory (EARL) was not designed to serve as sealed facility, nor to hold pressure, because the 4-bed CO2 scrubber in EARL is not yet configured to work with SAM, for this experiment we treated EARL as a sealed facility. To accomplish this, we wrapped the front door in a plastic tarp, using aluminum tape to seal against the door frame and floor. As the room would not be pressurized, there was no pressure differential from inside to outside, therefore the leak rate would be minimal.

Brendon Phoebe volunteered to be our test subject for all three human-in-the-loop runs. While the scrubber is designed to be computer controlled, and the Arduino-based systems are operational, we have not yet completed sufficient tests with the redundant, parallel manually operated system nor completed the programming.

As such, Brendon served as the operator for each of runs 2-4 (above).

Carbon dioxide was injected from the cryogenic chamber we use for plant experiments in the Test Module, elevating the CO2 in EARL to roughly 5,000 parts per million. In run 1 we simply monitored the CO2 level for 30 minutes following injection. In run 2 we monitored the CO2 level with Brendon inside, where his breathing added CO2 to the total volume of the EARL room. In run 3 the scrubber adsorbed CO2, thereby reducing the total mass of CO2 in EARL over the 30 minutes period. And in run 4 the chamber that held the zeolites was heated which causes the CO2 to be released. This causes the CO2 level to rise again.

During the runs, Kai and Matthias were station in the Test Module with radio communication with Brendon for coordination, timing, and confirmation of data collection start and stop times. Kai’s laptop held a remote viewing of the data collected by SIMOC Live for CO2, relative humidity, and temperature.

The experiment was, overall, a success and generated ample data for the ICES 2026 paper. The full results will be available with publication of the paper, and a link will be provided here with the release of the conference proceeds.

Design | Experiment | Components | Assemble | Fabrication | First Run

This phase of assembly requires in-house fabrication of key, custom components, fittings, and seals. University of Arizona undergraduate students Alyssa Ackerman, Brendan Phoebe, and Jeff Buskirk joined the SAM team mid October to work along side lead engineer Griffin Hentzen, and in 2026 will assume his role, as a team, when he ends his one year engagement at SAM.

The filters, gaskets, and seals internal to the chamber stack and between the chambers, and introduction of a commodity water chiller in combination with a heat exchanger provides a closed coolant loop to maintain adequate low temperatures for maximum efficiency of the total system.

Alyssa, Brendan, and Jeff each bring a unique experience, valued skills, and confident energy to this project, and are already contributing to the overall project at an incredible rate.

Design | Experiment | Components | Assemble | Fabrication | First Run

by Griffin Hentzen, ME

We are thrilled to enter the assembly phase of the project! We have all primary components needed to build the assembly, with many system components already mounted on the grid wall. Unlike most spaceflight hardware which is tightly packaged to maximize efficiency, our system has plenty of room. We are opting to make the assembly modular and spread components out as much as needed to make assembly, integration, and testing as easy as possible. This unit will be an experimental unit that we will want to be able to upgrade or alter at any given time.

The large chamber stacks have many different sections. At both ends, they contain diffuser chambers which simply allow the air to transition from a relatively thin tube into the full volume of the chambers. The largest chambers within each chamber stack are the sorbent and desiccant chambers. The sorbent chamber adsorbs CO2, but is sensitive to water vapor; the desiccant chamber adsorb water vapor to allow the sorbent chambers to function properly. The medium-sized middle chamber is a plenum chamber that contains a large check valve, and a side-exit port. The three small chambers are spacer & instrumentation chambers that allow for us to easily plug in power and data lines to components inside the chambers without compromising the seal quality. They are separate chambers to ensure modularity, and give us the flexibility to change around positions in the future.

Also mounted are the blower (blue), the blower controller (black box), and the vacuum pump (silver, white and black), which allows for us to pull a vacuum on the zeolites/sorbent to desorb them of CO2.

There are many more components in the system, including a number of valves, a heat exchanger, high-temperature tubing, and a healthy amount of instrumentation and wiring. So far we have primarily been fit testing and ensuring all components will mount correctly to the 80/20 wall. The mounting structure is designed to allow for maximum modularity and ease of assembly and maintenance compared to a system that is welded together, permanently in place. It allows us to move any given component up/down, left/right, or in/out.

Design | Experiment | Components | Assemble | Fabrication | First Run

The first batch of custom-built components has arrived in the mail and from the University of Arizona Machine Shop, a full-featured, solutions provider for all things custom built. The shop manager Larry Acedo has worked on dozens of space craft, world-class telescopes, and inventions of all specs and abilities. He maintains a small showcase of the myriad array he and his associates have built, over the decades. It’s worth a visit, even if you don’t have something for Larry to immediately entertain.

At the same time, Kai and Griffin hung the four rows of 3″ x 1.5″ 80-20 aluminum rails that will be the wall-mounted backbone of the 4-bed CO2 scrubber in the Experimental Air Revitalization Laboratory (EARL) at SAM. This system enables infinite adjustment in both the x and y directions, and can safely support hundreds of kilograms.

Design | Experiment | Components | Assemble | Fabrication | First Run

EXPERIMENT #4
Seeds prepping – September 2th
Seeds sowing – September 3th
Seedlings Transplant – September 22nd
CO2 injection and Experiment Start – September 23rd
Matthias Ingress – October 13th
Plants harvest and kill – October 20th
WBA Ends – October 26th
TM cleaning and prep – October 27th to October 30th

This experiment coincides with the World’s Biggest Analog (WBA) and introduced a human in-the-loop.

This spring brought us to the close of four years of design, development, and construction of a unique, world-class, hermetically sealed research facility for bioregeneration (air revitalization with plants) for long-duration human space exploration.

SAM is now actively hosting what will be the first of many years of experiments in which we grow a specific species of food cultivar to determine it’s growth rate and carbon sequestration against three Vapor Pressure Deficit values.

My graduate student Atila Meszaros and SAM Site Manager Luna Powell managed a perfectly executed test run of dwarf wheat, peas, and quinoa. The peas are a unique variety developed by Dr. Bruce Bugbee and his team at Utah State University. Smaller than standard, they produce a remarkably high seed yield–perfect for the Moon or Mars.

Furthermore, we are working with Dr. Lucie Poulet and her graduate student to determine key characteristics of the peas, including the density and dimensions of the leaves. All of this work is inspired by the legacy of NASA veteran Raymond Wheeler who was instrumental in motivating my dive into the world of bioregeneration in 2017 with my very first concept for SIMOC.

June through mid August saw completion of two full, six week runs of peas (2 weeks incubation at B2; 4 weeks in SAM) only to be met with the reality of one too many system failures and mistakes, forcing a total restart this past Thursday. That is the rigor of science–if the experiment is not done right, you do it again … and again. I am proud of Atila and Luna for not hesitating to set aside more than three months of hard, daily work in the name of solid science.

Our current experimental configuration is built around a nearly fully automated, computer controlled system that Atila, Luna, and Tanner Conrad, Research Technologist (under Dr. Murat Kacira) at UA CEAC assembled and programmed. It maintains a constant 800 ppm of CO2 such that by monitoring the amount of CO2 injected (from a cryogenic tank via gas manifold) we know the maturity of the peas and can plot, with a high degree of accuracy, the growth function and as such, ability for any food cultivar to revitalize cabin air.

The culmination of this series of experiments comes in October in conjunction with the World’s Biggest Analog where veteran SAM team member Matthias Beach will be sealed inside for two weeks. During the first week his CO2 will be sequestered by the peas (at least, that’s the hypothesis). On the morning of the 8th day he will harvest the peas, remove them from the habitat through the airlock for external processing and analysis, and then complete the mission with no CO2 removal to demonstrate the amount of CO2 that was being sequestered by the plants.

Learn more about this series of experiments …

EXPERIMENT #3
Seeds prepping – August 3rd
Seeds sowing – August 4th
Seedlings Transplant – August 18th
CO2 injection and Experiment Start – August 19th
Plants harvest and kill – September 16th
TM cleaning and prep – September 16th to September 22nd

This summer was one of adventure for the entire SAM crew.

Kai and Trent enjoyed a trip down the Grand Canyon mid-May with directors and volunteers for the National Space Society, the final voyage of this seasonal journey in memory of the incredible (and greatly missed) Anita Gale who departed planet Earth in May 2024.

Kai and Colleen attended the National Geographic Society’s Explorers Fest and then ventured on to Mongolia for six weeks, teaching English, exploring the foot of the country’s largest glacier, and kayaking wild rivers.

Kai Nevers and his partner Kate spent a month traveling around Greece and Italy … ending the trip with a 1 week hut-to-hut hike in the Dolomites.

Trent was wreck diving with the Explorers Club in the Great Salt Lakes.

Luna enjoyed time with family in rural Maine and sought refuge from the summer heat in Northern Arizona.

Griffin took his first trip overseas and presented two papers for SAM at ICES 2025, Prague.

Atila explored the beaches and jungle of his home country Peru.

Bindhu attended the Humans to the Moon and Mars summit in Washington D.C. followed by the Aerospace Medical Association conference in Atlanta, Georgia, related to the SAM MedBay project. She visited a colleague from the Analog Astronaut Conference in England, where she rode her first wave on a surf board, visited the Eden Project, and prehistoric Stonehenge.

Nathan explored lava tubes in Hawaii.

Shantano got his first, single author paper accepted to the CAIP conference, presented at the Sagan Summer Workshop for a hands-on project on occurence rate of exoplanets, and captured a thunderstorm and Saturn’s moon Titan on his phone.

And Matthias ventured to Devon Island with the Mars Society as XO for the Advance Team to prepare the Flashline station for Missions 17 and 18.

And somehow, despite the incredible travel, we got a lot done at SAM!

EXPERIMENT #2
Seeds prepping – July 2nd
Seeds sowing – July 3rd
Seedlings Transplant – July 17th
CO2 injection and Experiment Start – July 18th
Plants harvest and kill – August 15th
TM cleaning and prep – August 15th to August 17th