EVA

The presence of water on Mars has long been the subject of debate among scientists and the issue is far from being solved. Water cannot exist in a liquid state on the surface of the planet due to the low atmospheric pressure - about 8 millibars, 125 times less than Earth’s atmosphere.

However, water could exist on the surface of Mars in the form of ice, as in the polar caps. There is also the hypothesis that water in liquid form could be found underground, maybe trapped in water pockets in rocks.

If this is the case, it is important for two reasons to be able to locate these pockets. First, a human crew landing on Mars could tap the water in these pockets and use it either for their own use (drinking, washing, cooking) or to produce hydrogen to be used as fuel and oxygen to breathe. Secondly, if life is ever to be found on Mars, it is most likely to be in the form of bacteria.

Bacteria have been found on Earth in the most unlikely environments, such as at the bottom of oceans, several thousand of meters deep under a pressure of several hundred times the atmospheric pressure; in volcanoes; in deep ice; or at high altitudes of up to 70 km, etc. Bacteria can live without air but not without water. Find the water on Mars and you may find life.  
 

Dressing for an EVA

This geophysics experiment was proposed as a collaboration between scientists at the Institut de Physique du Globe de Paris (Dr P. Lognonne), the Royal Observatory of Belgium (Dr V. Dehant) and myself. It consists in deploying a line of 24 sensors called geophones, which are firmly planted in the ground and connected to a data cable, called a flute, which in turn is connected to an acquisition system.

A mini earthquake is generated artificially by hitting the ground with a sledge hammer near a trigger geophone. The wave propagates in the ground, reflects on an underground interface layer and eventually refracts on the same layer. All signals are recorded by the geophone flute and later analysed. From the results it is possible to extract information such as the average speed of propagation, the geometry and depth of the interface, and the type of underground material. It is proposed to conduct this seismic refraction method on Mars during a first manned mission.

The aim of today’s test was to assess whether it was possible to conduct this experiment in Extra Vehicular Activity (EVA) conditions, that is wearing a bulky EVA suit with backpack, boots and gloves. Well, believe it or not, it worked. It was exhausting but we managed to show that it can be done.

We started with the day’s briefing, munching on energy bars as we anticipated that lunch would have to be skipped, and we kitted ourselves out at about 10:30. Altogether four people were on the EVA: Robert Zubrin, Katy Quinn and myself plus Frank Vizard, a science reporter from Popular Science who observed the operations and returned before the end of the EVA. Charles Cockell, Bill Clancey and Steve Braham monitored the communications support for the EVA from the Habitat and Bill conducted an additional experiment on monitoring EVA human factors.
 
 

Working in the Habitat

We went to the same location as the dry run of two days ago. However, with the bulky EVA suits on it took us longer to lay down the geophone flute. At some point, my helmet was totally fogged up and as I could not clean it I just had to suck some water from the tube and expel it on to the inner surface of the helmet to remove the condensation. Not very hygienic, but it worked.

Later it started to rain and a westerly wind started to blow. A few other mishaps occurred such as not being able to bring the screen up to a visible brightness level when running the setting test on the acquisition system. In my defence I have to say that activating the keys on the keyboard with gloves was not possible and I had to rely on an additional tool to press the keys. This took quite a while, but it could eventually be fixed.

We successfully ran three series of tests, each involving ten shots with the sledge hammer. It was then time to pack up and go back to our Martian Habitat. The whole EVA activity, including donning and doffing the suits, took more than five hours. It was really exhausting but extremely interesting. I cannot wait to go back for another EVA, probably on Saturday.

Carrying out the EVA consumed most of the day and the rest of the time was shared between writing reports and interviews for the press, mainly the Discovery TV Channel. Our dinner was prepared by Steve Braham and consisted in a combination of couscous with vegetables and spaghetti with a chicken white sauce – a strange combination but excellent when you are starving!

There is now a storm with heavy rain and some snow is forecast for tonight and tomorrow, but moral is high on arctic Mars.