Bacterial wires explain enigmatic electric currents in the seabed:
Each one of these 'cable bacteria' contains a bundle of insulated wires that conduct an electric current from one end to the other. Cable bacteria explain electric currents in the seabed Electricity and seawater are usually a bad mix.
WOW!!!! don't want to even imagine what we do to these with the trailing fishing boats that sweep through sea beds with large masses ....
"Our experiments showed that the electric connections in the seabed must be solid structures built by bacteria," says PhD student Christian Pfeffer, Aarhus University.
He could interrupt the electric currents by pulling a thin wire horizontally through the seafloor. Just as when an excavator cuts our electric cables.
In microscopes, scientists found a hitherto unknown type of long, multi-cellular bacteria that was always present when scientists measured the electric currents.
"The incredible idea that these bacteria should be electric cables really fell into place when, inside the bacteria, we saw wire-like strings enclosed by a membrane," says Nils Risgaard-Petersen, Aarhus University. Kilometers of living cables
The bacterium is one hundred times thinner than a hair and the whole bacterium functions as an electric cable with a number of insulated wires within it. Quite similar to the electric cables we know from our daily lives.
"Such unique insulated biological wires seem simple but with incredible complexity at nanoscale," says PhD student Jie Song, Aarhus University, who used nanotools to map the electrical properties of the cable bacteria.
In an undisturbed seabed more than tens of thousands kilometers cable bacteria live under a single square meter seabed. The ability to conduct an electric current gives cable bacteria such large benefits that it conquers much of the energy from decomposition processes in the seabed.
Unlike all other known forms of life, cable bacteria maintain an efficient combustion down in the oxygen-free part of the seabed. It only requires that one end of the individual reaches the oxygen which the seawater provides to the top millimeters of the seabed. The combustion is a transfer of the electrons of the food to oxygen which the bacterial inner wires manage over centimeter-long distances. However, s
Royal College of Art's Innovation Design Engineering course in collaboration with Tufts University silk lab. Not as good as it sounds as it does not fully mimic the photosynthesis equation (spare C, H atoms)
Interesting stuff and I guess it does not need to fully mimic photosynthesis in the end. As long as oxygen can be produced from CO2 and water that would be great enough. Though the carbon has to be deposited somewhere (in some form) and I wonder how one could extract this efficiently. Maybe it can even serve some purpose (as the sugars are doing for the plant)
Plants have many valuable functions: They provide food and fuel, release the oxygen that we breathe, and add beauty to our surroundings. Now, researchers wants to make plants even more useful by augmenting them with nanomaterials that could enhance their energy production and give them completely new functions, such as monitoring environmental pollutants.
The mantles of Earth and other rocky planets are rich in magnesium and oxygen. Due to its simplicity, the mineral magnesium oxide is a good model for studying the nature of planetary interiors. New work studied how magnesium oxide behaves under the extreme conditions deep within planets and found evidence that alters our understanding of planetary evolution.
Interesting approach, but with 99.9% probability they will miserably fail (at least in terms of their time schedule) simply because the technology is untested. I haven't read the refs (which miss by the way important works of E. Ahedo et al. on magnetic nozzle acceleration by ambipolar effects), but
1. using water means that you produce oxygen radicals which will erode chamber walls (ionisation efficiency is not 100% and experimental tests haven't been performed yet).
2. Electronic excitation (and radiation), rotational excitation, vibrational excitation, and dissociation are all processes which consume energy and reduce ionisation efficiency drastically.
3. It is a miniaturised Helicon thruster. Theoretical analysis probably does not consider near field effects. Far field models are probably not applicable due to the size of the thruster.
I expect some surprises during thruster testing. In any case - good luck!
Apparently, there is only one qualification constraint regarding CubeSat propulsion which is related to volatile propellant. Since they use water as propellant and are also the owner of the CubeSat it is actually up to them how they qualify their thruster. Given that it is also possible to qualify the thruster within 18 months - since they define what "qualification" means.
Having an ocean on Mars would solve so many problems... btw, again this guy? Isabelle take a look at that : Tim Lenton is everywhere, last time he wrote half of our literature references on the tipping points study.
The battery is based on a liquid electrolyte that uses oxygen from the surrounding air to produce a high battery capacity (up to 27kWh per liter). Needless to say, this type requires an atmosphere to operate and who knows what environmental impacts may be
The SpaceX Falcon 9 explosion was caused by a failed strut that allowed a helium bottle to burst free inside the rocket's liquid oxygen tank, CEO Elon Musk said Monday. "One of those struts broke free during flight," Musk told reporters on a conference call to discuss the June 28 blast on what was supposed to be a routine cargo mission to the International Space Station.
I guess this is how it starts as they mentioned they will inspect struts individually before each flight. Also for the space shuttle they believed a rapid inspection between launches would be feasible, but in the end there was a need for individual assessment almost. And we haven't even considered human spaceflight yet.
as predicted, first failure, first inquiry board, first new safety procedures ... and certainly many more will follow and all will make sense but with the risk of loosing the competitive edge
Among the concepts to be studied by the Astrium team are a two-stage configuration with a Vulcain II-type or expander cycle cryogenic main-stage engine, a two-stage design with a methane/oxygen main-stage engine; and a three-stage configuration with solid propulsion first- and second-stage motors.
Link to the paper that is the subject of this article:
Olsson-Francis, Karen and Cockell, Charles (2010). Use of cyanobacteria for in-situ resource use in space applications. Planetary And Space Science, 58(10), 1279-1285.http://dx.doi.org/10.1016/j.pss.2010.05.005
Scientists on Sunday said they had gained insights into a remarkable bacterium that lives without oxygen and transforms ammonium, the ingredient of urine, into hydrazine, a rocket fuel.
Regarding our discussion on resource self-sufficiency of a Mars colony. Would it ever be possible (from a resource perspective that is..) A NASA report on availability of resources.
A self-sufficiency trade study described in Boston (1996) identifies the mission duration at which the development of local life support resources becomes advantageous. Within 30 days, without recycling, or with the equivalent leakage, it becomes advantageous to derive oxygen from local resources. The time constants for water and food are about 6 months and 3 years, respectively.