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Comment Follow the Nitrogen (Score 1) 99

Engineers, space physicists and tech magnates are quite talented in delta V, derivative trading and the Lambert problem but are, unfortunately, very poor biochemists. In recent times there has been much excitement concerning extraterrestrial water and very little consideration of nitrogen -- the reduced form is literally the stuff of life.
Given that 78% of the air you breathe is nitrogen, Mars has a paucity of 2% in its already tenuous atmosphere and that the Martian soil more closely resembles Clorox (TM) than anything what is your proposed Nitrogen source/budget? Note there is yet no evidence of vast subsurface nitrate deposits.

Comment Re:What is old is new again! (Score 1) 30

From Newman Craig J Nat Prod 2012 75 311-335 about 50% of FDA approved drugs (1940-2012) were derived from natural sources. It never totally went away but as you surmise the big Pharmaceutical companies cut back on these efforts when we went through the trend of combinatorial chemistry (which resulted in a decade long gap of FDA approvals with the consequence of sucky economic times for just about everybody).
What this work demonstrates is that there is a big chemical universe waiting to be found using advanced technology and some clever experimental design. But to me I think these researchers embody what you are complaining about because the really hard work is isolating the low concentration metabolite and then testing it properly. Also the 30 K secondary metabolites they found sounds suspiciously like semi degraded peptides which will no nobody any good.

Comment Re:... not sure what this really means ... (Score 2) 144

This is not a dim witted question. Actually it is a profound engineering question. The simple answer is to liken the fusion reaction to the coal burning in a steam engine; therefore in the end we could just be boiling water. The difficulty is that fusion occurs at temperatures of millions of degrees and any machine you can conceive of to capture the energy is necessarily going to make "contact" with plasma. There are a number of concepts about how to do this, google the "first wall" problem for a taste of the issues. In general though the engineering issue is not as important as learning how to make an excess of energy economically in the first place. A scientific problem ploddingly being picked at by very few concerted efforts.

Comment Density matches theory (Score 3, Interesting) 50

Here are some relevant space object mean densities. Mars 3.93 g/cm3, Phobos 1.87 g/cm3, Deimos 1.47 g/cm3, Mercury 5.42 g/cm3, Luna 3.34 g/cm3, Earth 5.51 g/cm3, Ceres 2.07 g/cm3, Vesta 3.45 g/cm3, Europa 3.01 g/cm3, Comet 67P/Churyumov–Gerasimenko 0.47 g/cm3. If Phobos and Deimos formed from a violent collision it might be expected that they would be dense rocky objects like our moon or Vesta. However it seems that these moons more resemble the icy object end of the density spectrum. Did they form during a wetter Martian era?
I think the take home message is that some exploring of the Martian moons is in order; a sample return mission would be much simpler than a Mars return with an interesting scientific purpose.

Comment Re:Dear Microsoft (Score 1) 387

Could we go one step further? Do you think that the ability to adapt to our natural hand-brain writing motion represents the next wave of technology?
Shouldn't this keyboard in front of me be replaced by an input device that is indistinguishable from pen paper?
I do complex math, it begins as jumbled scriggles and ends up in Matlab.

Comment Ceres it's cold out there (Score 1) 78

The solar irradiance at Ceres is about 150 W/m2...1/9th that of earth. It is cold out there in the asteroid belt in comparison to the moon or Mercury where surface ice is exposed only in polar permanent shadow. As reference the moons of Jupiter have no trouble maintaining a coat of ice.
My guess is that the surface of Ceres is like a charred marshmallow; organic long chain hydrocarbon on top forming a dark crust that protects a frozen interior of H20/CO2/Methane and ammonia. The white spot is a rupture out of which has gurgled up some salty water that is sublimating to space.
The question is can we skate on it?

Comment FM No Static at All (Score 1) 293

Guess the Norwegians don't seem to care...

Worry the bottle Mamma, it's grapefruit wine
Kick off your high heel sneakers, it's party time
The girls don't seem to care what's on
As long as it plays till dawn
Nothin' but blues and Elvis
And somebody else's favorite song...
FM No Static at All -- Steely Dan

Comment Novel but not that useful (Score 3, Insightful) 21

Not sure why this kind of cute 'inside baseball' research is being posted on Slashdot. Firstly there are many and better ways of screening for peptides -- the click chemistry trick is probably applicable only for this this proof of concept (toy) system. Good luck with a real protein. Secondly peptides are useful for research and totally useless as drugs. Thirdly the summary is really wrong here, the minimal in vivo data shown here does not come close to addressing the "complex milieu" of cells much less cancer much less Akt mutation driven cancer
So which member of the Cal Tech research team posted this slashvertisement? Congratulations on your Nature Chemistry paper. By they way it has gone to your head.

Comment Nitrogen is Organic Chemistry (Score 2) 228

You learn in Sci Fi and in dull HS Science that you are a carbon based life form. Now this is a very coal based thing to say; one could also very well say we are nitrogen based beings (or hydrogen/Phosphorus/oxygen etc). There's a whole lot of carbon in the inner solar system in many extractable forms but Nitrogen is the fixer. Why is it that acquiring enough nitrogen from the 78% that is in the air happens to be the one of the rate limiting steps for life? That 0.04% CO2 is not limiting.
The outer solar system is different, fixed nitrogen ammonia is abundant. Titan, Europa, and possibly Ceres?
Mars on the other hand had its Nitrogen blown away by the solar wind and since it is an essential ingredient for you nitrogen based life forms it would not be my first choice to set up shop.
For that matter, why not truck water and ammonia from Ceres to the moon and live in a warm place with a great view?

panic: kernel trap (ignored)