The last two days have moved along swiftly as the crew continues to rack up hours on their underwater extravehicular activities (EVAs). They have continued to successfully complete their mission objectives, and have dealt with several technical issues. The weather continues to be spotty for the topside team due to a strong easterly wind. However, we are still in a fully operational mode and have implemented plans to decrease the stress on the "topsiders" having to wait it out on the surface. One question that we've been asked many times is: "Will the recent oil spill interrupt your mission?" Due to our location in the Caribbean, just south of Miami in the Florida Keys, we do not think it will have any impact on us during the duration of this mission.
Mission Day 3 (MD3) was focused on similar EVA objectives as MD2. The crew was busy performing EVAs in both the morning and the afternoon. Like any other task, both the crew and the topside support "utility" divers had a steep learning curve to climb on MD2. Consequently, MD3 went quite smoothly.
At NASA, some of the tools that we use when preparing for spaceflight are "mock-ups". These come in many shapes and sizes and represent all types of vehicles, interiors, compartments, tools and pieces of equipment. Here at the Aquarius Reef Base, our friends from the National Oceanic and Atmospheric Administration (NOAA) and the University of North Carolina Wilmington (UNCW) have built some of the most functional and realistic mock-ups for spaceflight yet. They have built a full scale lander, a rover, ascent module, tunnel, airlock, large and small crane, ladder and more. To see them on the abyssal plain of the seafloor is truly an impressive sight.
In order for a mock-up to be functional, it must meet a lot of different requirements. First, it has to be cost effective. We're not trying to build the real vehicle, but a volumetrically accurate representation of it. Second, it has to be sturdy and safe. Building mock-ups for this environment can be challenging. They must be able to withstand the rigors of the tasks put to them, but also the effects of the current, the surge and of course the continuous effects of the saline ocean water. Third, they have to be functionally operational for our needs. In the case of NEEMO, for example, we are not trying to decide what material to use for building the vehicle, but how a human will interact with it. For instance, we're concerned about how hatches are located and sized, how cranes operate, how much interior space is needed in a vehicle and any other operational questions that might arise.