Postcards from Mars

Strength. Durability. Flexibility with minimal modification. This is the art of the science of materials manipulation with metal being ideally suited to the interior of a space craft (even one that doesn’t have rockets).

This week brought welcomed, cooler temperature, rain, and hail. The desert was alive again after a much needed storm to break the dry spell. And with that invocation of precipitation came a highly productive few days, the start of our last, long dash to the finish line in May, and first pressure tests.

Trent and Kai removed the steel frame of the original data collection terminal and kiosk. From 1987-1989 this structure served as a station for monitoring, collecting, and displaying real-time data feeds from the analog sensors in the Test Module. Data feeds were brought from within the sealed Test Module to the kiosk through flex conduit, a junction box, and PVC pipe to the kiosk, with pressure fittings and silicone rubber used to maintain air-tight fittings.

Now, with most sensors transmitting via a digital communication medium, a single USB, Ethernet, or wireless feed can route all the data generated by the Test Module. As such, the entire kiosk will be replaced by a single, simple podium where a SAM manager, visiting researcher, or tourist engaged in a presentation can view data via a laptop.

While a dozen PVC conduits were terminated, filled with expansion foam, and buried in concrete, two conduits are retained: one for electrical power, the other for Ethernet and USB. Why? A hard line provides IT support on the outside of the habitat to provide direct support and potential firmware upgrades for equipment that misbehaving. While not desired and certainly not engaged regularly, this direct support does not require a break in the seal and simulation.

At the same time, Kai and Trent were eager to remove the last of the old, long-since abandoned and very much displeasing pipes and junction box from the space between the exterior and interior doors. The steel floor was cut free, pipes cut low, and concrete poured for a new, clean, elegant entrance. Next, the walls of this small space will be sanded, primed, and painted with the installation of the new, primary electrical panel.

Thank you Tim and Terry for helping with a six bag concrete mix, pour, and finish!

In March we selected a window tint to apply to the lower windows in order to reduce the visible light transmission to that of ambient light on Mars. Owner of Tucson based AGTP Window Films Greg Spencer (“Greg the Tinter”) and his son Tristen arrived at 9:30 am Tuesday morning and within minutes were engaged in prepping, cleaning, and applying large sheets of the window film. As with hanging dry wall, this is one of those tasks that the experts make look easy. Yet, if ever you have tried to do it yourself, you quickly learn the real challenges.

Greg and Tristen pealed, soaked, and placed thirteen sheets of window film, then used a squeegee to remove all air bubbles before the adhesive set and dried. The end result is simple beautiful. Not only did we achieve the desired, reduced ambient interior light, but these thirty year old windows now appear brand new. The film selected provides a reduction of in light with a minimal reflection such that when research team members are working inside of the SAM greenhouse at night they can yet enjoy the Moon and starlight outside.

On the west side of the Test Module two of the four windows were cracked. Luckily, we are going to remove two when the adjacent shipping container is attached to form the workshop and corridor to the crew living quarters. In preparation for application of the window tint, we had to swap the windows such that the two good windows were relocated to the north and the two broken windows temporarily placed in the south positions.

Trent, Tim and Terry, and student volunteer Michael Blum tackled this strenuous process with expertise, using professional suction cups and a lot of muscle (each panel weighs more than 250 lbs).

With the rather dismal failure of the cherry picker to provide an agile platform for our work on the exterior of the Test Module, we rented scaffolding instead. While a bit tricky to transport two double-stack sections on a 4×8 trailer, we managed and in fact prospered. By the end of the third day, Trent and I (Kai) could tear down and reassemble the entire rig in just under an hour!

We applied two coats of a 100% silicone elastomeric to the top two rows of glass panels and the structure between. As with the top of the Test Module, this highly reflective coating helps us more closely approximate a habitat on Mars by rejecting the unwanted radiation, reducing the visible light and thermal gain, and for our terrestrial application, drastically reducing the thermal load.

With each side of the TM, West, South, East, and then North we found the interior temperature reducing, the glare diminished, and quite unexpectedly, a sense of improved space. Where we feared the elegant space frame and all-glass structure might lose its futuristic style, instead it gained comfort, now more a habitat than an industrial structure.

Sometimes, you find water in the most peculiar places.

As we moved to paint the interior of SAM we became more acutely aware of both the location and density of the rust. Two full weeks after we last washed the interior of the Test Module, ceiling to floor, there was still rust colored water seeping from certain places. In fact, there is a fairly significant pattern—the heaviest rust was always on the left-hand side of the four corner support beams. How could that be possible?

Upon further inspection, we discovered that the mounting plates for the space frame each had four holes, but no more than two of them, often just one were filled with a bolt. The others were simple openings into the massive, horizontal steel beams. We believe that over the years the humidity condensed on the inside of the windows, rolled down onto the “V” shaped window sills, pooled and ran onto and then into the support beams by means of the mounting plate holes. There it sat, unable to further explore … until the water, oxygen, and iron worked their magic to turn much of the lower section of the Test Module to the color of Mars.

To test this theory we drilled a 1/4″ hole at the end of each beam. Sure enough, the water poured right out and into the waiting bucket. Dry at last, we are preparing to prime and paint.