A few months ago NASA announced that there is a non-trivial probability of water on Mars. Data from the Odyssey Mars Orbiter
http://mars.jpl.nasa.gov/odyssey/
show sizable areas with water ice buried in the Martian southern and northern hemispheres. The water is so common poleward of sixty degrees that its volume probably exceeds 10,000 cubic kilometers.
The measurements do not detect water directly, but rather look for neutron and gamma ray signatures from the ground. The neutron signal is created by cosmic rays striking Mars. These liberate high speed neutrons from atoms near the surface. Some head directly to space at very high energies, but most that make it to the Odyssey loose energy by scattering with other neutrons in surface material. It turns out that hydrogen atoms are particularly good at slowing these neutrons and hydrogen-rich matter has a characteristic signal consisting of a dropoff in medium energy neutrons..
It turns out that excited hydrogen atoms also emit gamma rays of a well defined energy which, combined with the neutron decline, is an excellent sign of hydrogen. Since rock forming materials are very low in hydrogen, water is much more likely. Since Mars is cold at the poles the water is likely to be water ice. There are some areas that are too warm for water ice to form, so there is a likely hood of find OH mineral bindings - eg.. clay.
The measurements indicate that the debris covering the ice is anywhere from 30 centimeters to a meter thick. The ice is close to the surface, but it is not possible to determine how thick the layer is (the ice water volume stated above is a conservative guess).
The fascinating thing is that current analysis indicates the near-surface material may not be porous enough to hold as much ice as is indicated ... some people claim this is evidence for a glacier and evidence of glacial erosion has been found in the southern hemisphere adjacent to a high ice region.
Of course there have been non-scientific discoveries related to Mars of even greater excitement:
"Irrigation, unscientifically conducted, would not give us such truly wonderful mathematical fitness (as we observe in the Martian canals) ... A mind of no mean order would seem to have presided over the system we see - a mind certainly of considerably more comprehensiveness than that which presides over the various departments of our own public works." Percival Lowell, 1908
"Martians Build Two Immense Canals In Two Years. Vast Engineering Works Accomplished in an Incredibly Short Time by Our Planetary Neighbors." - NY Times headline. August 27, 1911.
It is interesting to speculate on the effect of discovering intelligent extraterrestrial life. Many speculate that it would change humanity. Somehow I think not - a few generations ago the press pushed it as scientific knowledge and there was no real social impact (other than the inclusion of this information in many new religions.)
BMW has been pushing hydrogen fueled cars for a few years and seems to have made considerable progress.
http://www.edmunds.com/news/innovations/articles/46906/article.html
A hydrogen powered car has many similarities to an electric car ... no local CO2 emissions, no local hydrocarbon emissions, etc. It is probably worthwhile to think of the hydrogen as a storage mechanism. Someone how you need to create it and, ideally, that mechanism should be environmentally sound (electric cars are something of a sham if connected to a coal fired grid - the efficiencies aren't that much better than a high efficiency internal combustion car).
Distribution and storage of hydrogen are non-trivial issues in any hydrogen scheme. Electric cars have pretty much given way to gas-electric hybrids and energy storage is probably the largest reason.
Solectria is an MIT spinoff that produced one of the first practial electric cars. For a few years they produced some interesting conversions and were probably the only concern that produced vehicles that outperformed the GM electric car.
Unfortuantely there was no market for their stuff...
http://www.solectria.com/products/accomp.html
They had a business model that required a small number of environmentally minded people to buy their stuff. In addition to the problems associated with pure electric cars, they lacked a dealer and service network. A few well healed people like Alan Alda bought electrics, but it wasn't enough.
The EFF is weighing in on the RIAA vs Verizon case and is claiming that parts of the DCMA are unconstitutional. Bully!
http://www.eff.org/Cases/RIAA_v_Verizon/20020830_eff_amicus.html
Recall that the RIAA and their motion picture equivalent, the MPAA, have effectively purchased Congress. You may want to get in touch with your congressperson if you disagree with the recording industry before it is too late. Votes do count - especially in tight election years.
5:58:05 AM 
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