Imagine your head in an empty fishbowl with air blowing gently on either side; that's pretty much what a simulated spacesuit helmet is like. Just as for the fish in the bowl filled with water, there is a transparent mural between your living environment and that of your surroundings. Nevertheless, in both cases it pisses you off when big dumb humans tap on the glass.

What brought about this rumination on the similarities between the sentiments of fish in an aquarium (of any size) and those of humans in a spacesuit helmet? Well, today was our first EVA -- for those of you not yet fluent in eye-chart that's Extra Vehicular Activity, which means we went outside and walked around. As you can see though, 'went on EVA' sounds way sexier than 'went for a walk' so we'll stick with the dirty talk.

The Crew Commander, Jan Osburg, and our resident astronomer, Jenny Rome, accompanied me on our two-and-a-half our trek around the simulated Martian 'hood. We went out around noontime so that Jenny could take some measurements with a sextant (used for daytime marine navigation for hundreds of years) as a backup navigation system for roaming the Martian terrain.

You might wonder though why we're scraping the bottom of the navigation barrel by reverting to a technique that was invented well before Newton even penned his laws of gravitation. The reason is that it is, not only hard to shlep an entire GPS system to Martian orbit but also, impossible to use a compass on a planet with no magnetic poles. We take for granted Earth's magnetic poles to find direction but Mars does not have a uniform north-south magnetic field, thus the sextant for daytime navigation. Besides, as anyone knows who has had a computer or any other electronics act funny on them (never heard of that, right?), it's nice to have a low-tech backup plan to do something you need to know at all times (e.g., your location).

As part of my research, I took radiation measurements on the terrain all around the Habitat. Unfortunately though, there's going to have to be a second take for those measurements because guess what? Yep, the electronics acted funny when recording the data and the low-tech equivalent of Jenny's sextant does not exist for radiation measurements.

Nevertheless, the first real EVA was very cool and it definitely makes you feel the whole astronaut thing when roaming the surroundings -- even that itch on the end of your nose that you can't scratch for like two hours.

Jason Sherwin, PAO
MDRS Crew 47