Postcards from Mars

Sculpting Mars at SAM: Days 12-15

Painter Danni gives bold, three dimensional form to the carved, simulated stones at SAM, Biosphere 2

And then came the scenics, a breed of artist unlike the plasterers or the sculptors before them. Quiet like the brushes they employ, subdued like the hints of red, butterscotch, and gray applied, Juan, Danni, and Christina also see the world in three dimensions—not as massive blocks of carved foam or layers of sprayed concrete, but in concentric applications of paint that build depth in color through time.

Referring to the same set of laminated photos as the two prior teams, the scenics apply dark hues beneath overhangs to create permanent shadow, and they create a sense of time through the hi-lights on the leading edges of rock ledges, mineral stains from long forgotten (even if geologically recent) movements of water. And when Danica or Kai would note a synthetic rock surface too bright or too bold for the atmosphere of Mars, within minutes color theory became color reality and the issue was resolved without hesitation or complaint for the second or third effort on that same section of the SAM Mars yard.

By |2024-05-05T21:24:05+00:00May 2nd, 2024|Categories: Construction|0 Comments

Sculpting Mars at SAM: Day 9

First coat of shotcrete applied to the Mars yard at SAM, Biosphere 2

The transformation of Polystyrene foam blocks into a Mars landscape requires vision, skill in sculpting, shooting concrete, and painting; and effective management. The first and last are exemplified by Red Hen founder Danica Vallone who maintains a relationship with some 250 individuals working in set design and construction, and her brother and production manager Demian Vallone who brings patience, diligence, and hands-on collaboration to the construction floor. At the SAM Mars yard Danica and her team have transformed drawings and photographs into three dimensions, demonstrating a deep understanding of form, texture, and color and the physical tools used to employ them.

The sculptors (as noted in prior blog entries) hold what is perhaps the most challenging of the processes— making those first cuts into the massive blocks of foam with a vision toward the end product that they may never see. This process is principally one of subtracting material, cutting into square blocks to remove initially large and then increasingly smaller pieces using hot wire knives, chain saws, horse brushes, three pronged picks, and an assembly of home-built hand and power tools. Material is added too, building beyond the otherwise imposed limit of a wall or corner, as with the rockfall in the southeast corner of the SAM Mars yard.

With the shapes established, the plaster crew covers the foam with a thin layer of a custom blend of Poly-bond structural concrete, sand, and adhesives designed to bond to foam. This concrete is tinted to establish a base color such that the final, painter crew can work from that base color with less effort and material, as compared to starting from a standard concrete gray.

While Hollywood sets built from foam are typically covered with 1/8″ concrete, thicker for areas on which actors might walk, the SAM Mars yard is 1/4″ nominal with the west wall K-rock covered in expanded steel, steel mesh, and in some areas up to two inches hand-troweled concrete.

Three sculptors were at SAM for eight days. The four plasterers are slated for just two days (starting today). And as of this coming Sunday two painters will be at SAM for four days. Each crew brings to this project some of the finest talent in Hollywood, with individuals who have two or three generations in skill and experience in their respective trades. The quality of production against an impossible timeline has been truly awe inspiring and points directly to Red Hen’s ability to manage such a complex endeavor.

BELOW: Luna Powell scatters real stones obtained from a local quarry on the shelves and outcrops of the north wall as the plaster team applies the first layer of shocrete to the south wall of the SAM Mars yard. The blue color is a layer of “Weldcrete”, a kind of chemical adhesive that helps the Polybond-based shotcrete adhere to the foam.

By |2024-05-05T21:24:44+00:00April 26th, 2024|Categories: Construction|0 Comments

Sculpting Mars at SAM: Day 8

Director of Research for SAM Kai Staats applies nylon rope to define the pathway of gypsum.

(Above) Kai Staats installs simulated pathways for Mars gypsum deposits—nylon rope pinned to foam blocks to be covered by shotcrete and then hand painted, perhaps encrusted with real minerals embedded in an epoxy resin in a later phase.

The sculptors completed their work in foam, applying final textures and geological interfaces while SAM team member Matthias applied expanded steel and mesh to the K-Rock feature, reinforcing the areas on which SAM crew members might walk while on EVA. The existing concrete slab was covered by rose paper before Demian of Red Hen sprayed the blue Weldcrete adhesive, providing a chemical adhesion layer between the foam and shotcrete.

By |2024-04-28T18:00:25+00:00April 25th, 2024|Categories: Construction|0 Comments

The Color Palette of Mars

A comparison of the raw image, corrected image, and Earth-light image from a Curiosity rover photograph. Courtesy NASA / Dr. Jim Bell.

Color calibration target for Mastcam-Z on Mars rover Perseverance

In the SAM Mars yard at Biosphere 2, the sculpted foam provides the robust shape of sedimentary layers, lava, solidified dunes, and rockfalls that define the very challenge of the geologist to unravel time. The application of the concrete gives solid form and texture to the otherwise too fragile structure made principally of trapped air. And while the two of these alone are ample to give visitors to this Mars yard a story to discover, it is the subtle shifts in color that make clear the differentiations of an ancient lake bed from the unconformity on which it lies or the iron concretions about to break free from the shelf on which they lie.

But when all the images captured by rovers on Mars for more than forty years are digital in origin and processed by computers, How does one know the true colors of Mars?

We called upon the distant Spirit, Opportunity, Curiosity and Perseverance rovers, reviewing myriad photos they have generated against the same color metrics applied to the photos received on Earth by NASA and countless university students and researchers. The on-board Mars rover color calibration targets provide a baseline to inform how one might adjust the pixel values, from the raw image to a color balance given the atmospheric conditions of that day, to what that landscape might look like if on Earth instead. The latter becomes important as we compare features on Earth to those on Mars in order to ascertain their origin.

More carving, color selection, and completing the lava tube at SAM, Biosphere 2

SAM team member and planetary geology student Tasha Coelho built an image deck based on her work in Dr. Jim Bell’s lab at the School of Earth and Space Exploration, Arizona State University. Luna Powell then prepared six sample tints for the baseline concrete color upon which the painters hired by Danica Vallone of Red Hen Industries will push and pull highlights and shadows to give this one-of-a-kind construct its own life.

By |2024-05-05T21:46:30+00:00April 24th, 2024|Categories: Construction|0 Comments

Sculpting Mars at SAM: Days 4-6

Sunday, April 21 began with an all-hands team meeting led by Danica Vallone. The prior two days with geologist Christopher Hamilton has altered the design to a degree that required a reset for some of the design expectations. Kai, Tasha, and Luna had printed a few dozen more images at various sizes and zoom factors. Danica then pinned them to the design board, a 6″ thick foam sheet with a marker rendering of the south wall, where each photo provided the required detail for the sculpting team to move ahead.

Monday, April 22 saw the sculpting team regain their anticipated rhythm with steady forward progress, the otherwise nondescript block of foam becoming recognized features, even to the untrained eye: a massive rock fall over an ancient lava flow adjacent to an even older evacuated lava tube.

Tuesday, April 23 began with a spray foam team arriving from Phoenix, setting up their air flow tent, and then applying a #4 density foam to the inside and outside of the rebar, chicken wire, and burlap lava tube built by Matthias, Luna, Kai, and Sean. During the spray foam endeavor, Kai took the sculptors Steve, Rob, and Kat on a tour of Biosphere 2.

Lava tube set and strong enough to walk on (but we won’t), the sculpting team returned their work (donning respirators) while the spray foam crew cut loose the over-spray and cleaned up.

By |2024-04-28T02:04:28+00:00April 23rd, 2024|Categories: Construction|0 Comments

Sculpting Mars at SAM: Day 3

University of Arizona planetary geologist Dr. Christopher Hamilton guides Arizona State University planetary geology student Tasha Coelho in the design of the Mars yard at SAM, Biosphere 2

As the Red Hen team moved into the afternoon of its third day in construction of the SAM Mars yard, University of Arizona professor of Planetary Geology Dr. Christopher Hamilton arrived for his first visit to SAM. Following a brief introduction to the project and tour of the initial representation of geological features on Mars, Chris dove in with the full fervor and intent of an actual geological survey and research project.

Over the course of Saturday afternoon and Sunday morning Chris spent the better part of six hours with Director of Research for SAM Kai Staats, ASU planetary geology student Tasha Coelho, and founder of Red Hen Danica Vallone to guide development of details for features already carved in foam, then formulate the juxtaposition of layers not yet sculpted in order to tell a cohesive story for the total, exposed stratigraphy. Once complete, the SAM Mars yard will tell a realistic geologically story.

Kai, Danica, Tasha, and Chris moved between the Mars yard and the SAM Operations Center to compare photographs of rock layer examples on Earth and Mars to the proposed layering of this unique facility, then print and laminate images for the Red Hen sculpting team to employ.

Chris was tenacious, generating on-the-fly a complete strata profile with which the SAM geological story can be understood. Or for those engaged in an EVA of geological discovery, investigate the layers and features presented in order to generate their own map, then compare to the intended sequence developed by Chris.

By |2024-04-29T13:35:14+00:00April 20th, 2024|Categories: Construction|0 Comments

Sculpting Mars at SAM: Day 1

Robert of the Red Hen team sculpts Mars geology features into foam at SAM, Biosphere 2

Red Hen Industries has returned to SAM, and this time they brought more than a set rescued from a Hollywood landfill. founder Danica Vallone and manager Demian Vallone arrived with sculptors Steve, Kat, and Robert. This first of three crews will be on-site for one week, followed by the crew that will shoot concrete over the sculpted foam, and then the painters who apply the final look and feel of the Mars geology.

Matthias, Sean hanging tarps around the Mars yard construction at SAM, Biosphere 2 SAM team members Luna Powell, Matthias Beach, Sean Gellenbeck, and Kai Staats are on site, working in shifts to provide support and clean-up for the Red Hen team. This is following a month in specific preparation, each day crossing off items on the long list of TODOs, including the purchase of tools and products to support the foam carving, shipping a specific blend of concrete from the Arizona/California border, hanging 200 linear feet of plastic tarps from the roof structure to contain the foam bits and eventual concrete, and a system for containing the foam for eventual recycling or integration into “styrocrete” such that nearly none of the product ends up in the landfill.

Day 2 starts at 7 am tomorrow and runs again until 8 pm, and so on for nearly three weeks. Hollywood never sleeps!

By |2024-04-29T13:35:52+00:00April 18th, 2024|Categories: Construction|0 Comments

Designing Mars at SAM

Mars yard at SAM render by Bryan Versteeg

Mars yard at SAM model by Bryan Versteeg |

In 2023 Kai invited Dr. Jim Bell to visit SAM. Dr. Bell is a world renowned planetary geologist at Arizona State University, School of Earth and Space Exploration, and designer of the ‘Mastcam’ cameras for the Mars rovers Curiosity and Perseverance. They reviewed the then small Mars yard “sand box” filled with crushed basalt, and discussed the ultimate expansion to a 2600 sq-ft facility complete with 10-12 foot high crater walls.

Together they considered three possibilities:

a) Take a single volcanic or impact crater on Mars and shrink it down to something that would fit within 2600 sq-ft. The challenge would be that we’d lose the detail of the features by the very function of miniaturization; or

b) Take a life-size feature such as a cliff band or gully bottom on Mars and recreate it, centimeter for centimeter adjacent to SAM. While this would give visiting crew members a very realistic EVA experience, the shelf-life for our Mars yard would be limited to the relatively narrow set of geologic features in a few hundred square meters; or

c) Build an amalgamation of features taken from various sites on Mars. This final approach results is a bit of a Frankenstein monster but is far more interesting, has a greater shelf-life, and can be modified in the future without geologic ramification.

APRIL 20, 2024
d) With the transition from an intended rebar, lath, and concrete construction medium to carved foam and shotcrete, it became possible to fabricate a realistic assembly of diverse features on Mars in the confines of a single space, and in so doing, build a world in which the represented geological layers tell a nearly complete story of millions of years of construction and erosion. Learn more …

In preparation for the arrival of Red Hen Industries and their Hollywood set construction crews, Kai once again reached out to renowned space architecture visionary Bryan Versteeg (top image) to generate a rough 3D model as a means to visualize the initial parameters of this massive undertaking.

In parallel, ASU School of Earth and Space Exploration undergraduate Tasha Coelho assembled a document that explores the varied types of features that might be represented in the SAM Mars yard geology, building on the initial photographs captured by Matthias Beach in the fall of 2023 with her own deep dive into the NASA and ASU image archives.

The features considered include: anthropogenic features, concretions and buried pebbles, conglomerates, gullies and talus slopes horizontal striations and outcrops, linear color variations, mud cracks, recurring slope lineae ripples, and veins and ventricals.

More than 100 images from the Curiosity Mars rover were studied, two dozen printed and laminated as initial guides for the Red Hen crew.


  • Clumps of minerals formed when water soaked the rock long ago
  • Resistant to erosion
  • Some are close to being fully revealed
  • Example: Martian Blueberries (Hematite, an iron mineral). These are also found in Utah’s petrified sand dunes. They become superficial (meaning, separate from the stone in which they formed) as surrounding sandstone/mudstone erodes away. These were discovered by Opportunity the same day it landed.


  • Rounded pebbles bound together with varying degrees of round
  • Nearby loose pebbles that have dropped out of the conglomerate
  • Evidence for fast flowing water; needed to mobilize and round heavier rocks

Horizontal striations

  • Buried sand dunes
  • Fine grain
  • Cross-bedding indicating different flows of water OR whole rock unit moved
  • Horizontal Striations
  • Fracturing


  • Fluid-rock interactions
  • Water carrying minerals and filling cracks in rocks
  • More resistant to erosion compared to surrounding rock
  • Dark base colors with light features (calcium sulfate aka gypsum}


  • Wind carved rocks
  • Wind blown grains erode and smooth surfaces, similar to a sand blaster
  • Resulting rock can show prevailing wind directions (learn more)

Recurring Slope Lineae

  • From orbit these features appear to be meters wide and kilometers long; might also be seen on smaller scales
  • Different theories for formation:
    – CO2 sublimation
    – Seasonal heating melting sub-surface briny water
    – Hydrated clays
    – Dry landslides

Anthropogenic features

  • From rovers/humans attempting to learn what lies beneath the surface
  • Educational opportunity
  • Reveals unoxidized layer

Mud Cracks

  • Floor features, or on top of flat rocks

Subsurface Water / CO₂ Ice

  • Newly revealed subsurface ice imaged by Phoenix and HiRISE
  • Have only been observed on the ground, not on vertical outcrops (need to verify)

Gullies + Talus slopes
These are not applicable to the size and scale of the SAM Mars yard.

Water (or CO₂) ice in cold traps
These can only be imaged from orbit, as with Korolev crater.

By |2024-04-29T14:21:57+00:00April 12th, 2024|Categories: Research & Development|0 Comments

SAM update: week of April 8

SAM model by Jason Francois

The following is the weekly update written by Kai Staats to his team, as completed each week for the past three years.

SAM Working Group,

Kai, Trent, Matthias, and Bindhu in Fredericksburg, Texas for the total solar eclipse 2024 Matthias, Trent, Bindhu, and Kai (that’s me) found each other in Texas for the eclipse and an ad hoc post-viewing lunch. On the way back to Arizona Trent and Matthias visited the Midland human-rated vacuum chamber with intent to expand the CHaSE offerings for pressure suit and related equipment testing. I worked all day Friday on the drive out and back again Tuesday with phone calls and support of Luna’s research, coordination with Red Hen Industries, and more.

As we are all aware, following the highly successful Imagination I crew at SAM and our well deserved week off, we’ve been focused almost entirely on preparation for the final major construction effort at SAM—the Mars yard crater.

Here at SAM Luna, Matthias, and I have slipped into a modified work program—no longer pushing against an impossible list of TODOs at a breakneck velocity; rather we are moving day to day, hour to hour, focused on a sequential list of projects that need to be done in preparation for the Mars yard crater. Our list of TODOs is maintained more on the black board than in digital form, which is ok given that we are just one month from completion of this major build session and the Analog Astronaut Conference.

Luna has applied her expertise in research (and shopping) to a running list of key elements needed for SAM in the coming month. In particular, she has found the elusive Polybond cement mix required for shotcrete applied to the foam sculpt of the Mars yard crater, and after more a week of research and phone calls secured the required 76 bags, scattered as they are across the state.

Matthias has a solid list of TODOs, from Ops to the Mars yard to electrical work in the lung. Today Matthias and Kai made a Home Depot run to secure another trailer of primary supplies required for the Mars yard construction effort that begins next week. Matthias, Kai, and Luna will tomorrow (Thr) complete primary construction of the synthetic lava tube from rebar and a new, wood super-frame to provide greater stability before the spray foam and cement are applied.

Ezio and Franco made good progress on the new SIMOC Live stand-alone unit, a single Raspberry Pi Zero with sensors that serves both as a data collection point and web server for local or remote web visualization. It’s an impressive, compact unit that could easily be packaged in a case smaller than a deck of cards. First prototypes will be shipped to test agents and the Lunares habitat analog for extensive testing prior to the World’s Biggest Analog, in which each analog will receive a similar stand-alone or (more likely) an ad hoc mesh array (as was in SAM for Imagination I).

HiRISE image and data, Arizona State University Jason has completed a revised and highly accurate 3D model of SAM (see top) following his visit in February. Bryan will tomorrow (Thr) deliver his updated Mars yard 3D model for use as a rough guide and visualization tool. I am working with Tasha (ASU) to build a set of hi-res images, again a guide for both the Red Hen and SAM teams.

Bindhu is working on an updated set of procedures for preparing SAM for team arrival, an updated Cuff List, design of the Med Bay, continued effort for the SAM photo book, an umbrella IRB, and more as these efforts carry into the summer between her adventures to Nebraska and Namibia.

Chris continues to support Ezio as they try to determine why the Raspberry Pi at SAM is going down every hour after a power outage (even with the UPS). Very frustration and confusing.

Sean is working with Dr. James Knox (formerly at NASA) for the CO2 scrubber design, preparing to host a 3 days workshop on algae here at B2 and SAM, and arriving to SAM in a week to assist Matthias with replacing the Mars yard poly panels in the midst of the chaos of the Mars yard crater construction.

Sadly, Ezio departs a week from Friday. He has been instrumental in the success of our SIMOC Live air quality monitoring and data collection program at SAM, and diligent in maintaining an organized approach to a highly complex project with many avenues to explore.


By |2024-04-29T13:59:29+00:00April 10th, 2024|Categories: Construction|0 Comments

A juggling act to remember

“When Danica Vallone of Red Hen Industries and I first discussed her proposal for how to build the SAM Mars yard, over dinner with Grant Anderson in January, I had already spent several months pursuing a more traditional rebar, metal lath and concrete or fiberglass mold approach. The right vendor for the right price had eluded me, with prices doubling since my first calls in 2021. In my mind foam felt too soft and something of a crumbling mess that could never successfully simulate the many features of a Martian landscape.

In the midst of our mutually busy schedules we traded my project needs against her team’s prior examples, then dove into the complex logistics for what would be a breakneck velocity in construction to finish in time for the Analog Astronaut Conference at Biosphere 2, third year in a row. We had to construct 180 linear feet of a Mars crater wall around a 2,600 sq-ft facility—fully sculpted, covered in concrete, and hand-painted in just 13 days. Nuts!

Once I was convinced this was not only possible but that it was in fact the ideal combination of media, we had to figure out how to get everything in place, in time. Danica had to pull sculptors, plasterers, and painters in southern California with absolute calendar precision between myriad other, established projects including a gig at South-by-Southwest and the total solar eclipse. My team had to wrap-up restoration of our Operations Center, install a point-to-point WiFi transmitter; complete, install, and test SIMOC Live v2.0; install the new hydroponics rack, host the third crew at SAM, and build a synthetic lava tube from rebar, chicken wire, and burlap cloth. Why not?

We then dove into the long shopping list provided by Red Hen in preparation for Mars yard construction including two semi-truck loads of foam blocks, buckets, garden hoses, rolls of paper, massive plastic tarps, a new 60 gallon air compressor, and a pallet of a Polybond cement mix shipped from the Arizona-California border, and more.” –Kai Staats, Director of Research for SAM at Biosphere 2

By |2024-04-29T13:57:02+00:00April 5th, 2024|Categories: Construction|0 Comments
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