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Comment Re:More elegant: arctic tern (Score 1) 37

For sure birds *are* solar powered, where do you think the energy for making plants, other animals, and for moving air is coming from?

The point with clean energy is that the time interval between the arrival of solar energy on earth and the moment we use it, it transforms into heat and is finally released into space as infrared radiation should be short with respect to the longest time-scale of our ecosystem, so as to not disturb it too much. In this way the carbon released into the atmosphere remains bounded.

Jet planes use oil which normally does not participate to the ecosystem. Oil needed 100's of millions years to accumulate, if not more, and releasing this carbon in a couple of centuries is not the smartest idea. The solar or not origin of oil is irrelevant.

Comment Re:Old things (Score 1) 389

Taking literally the biblical texts is nowadays no longer compatible with the aim of staying intellectually honest. Tons of scientifically based evidences conflict with your unjustified claims (biblical texts are not science based).

Remind some scientifically based evidences:

1) The sky show us plenty of evolving objects at distances that light needs thousands to billions of years to reach us.
2) Any serious geologist observing km thick layers and layers of rocks arrive to the conclusion that most of the stones and fossils must be millions to billions years old and made by processes like sedimentation or volcanic eruptions.
3) Archeologists can date the spread of human ancestors over the Earth back to millions of years.
4) Historians can document the emergence of civilizations from the Neolithic period well before any epochs you mention, such as 8'000-10'000 BCE in Egypt and Mesopotamia.
5) There is no geological evidence for a world wide flooding as described in the Bible. The required amount of water is just not available on Earth.

Believing in biblical chronologies together with not ignoring scientific evidences must lead to the conclusion that the universe was created by a god devious enough to introduce at the same time uncountable false evidences (like all the photons coming from deep space) for the existence of a consistent but fake universe, millions of times older than the biblical one. .

Comment kW or kWh? (Score 2) 245

From BG blog one can conclude that the author belongs to the category of people unclear about the difference between a quantity of energy and a rate of energy production. To his excuse the common poor choice of kWh instead of the SI J (Joule J, 1 kWh = 3.6 MJ) as energy unit is just making energy discussions more confusing.

 

Comment Mean and fluctuations (Score 2, Informative) 222

The climate has always been a highly fluctuating system where extreme temperatures oscillate over seasons and location by, say typically +/-20K (Kelvin), around a mean value around 287K, slowly growing. In some countries the fluctuations are larger, in some others smaller. All the discussion about the human-induced warming is about the effect of changing this mean value by a couple of K (now +0.5K, in the next century by +2-4K). So even in the most pessimistic scenarios the warming remains in amplitude a small fraction of the typical annual fluctuations. No wonder that it will be difficult to prove that any extreme fluctuations will result from the warming.

Comment Real advantage (Score 2) 108

One cannot escape the fact that bigger apperture telescopes can record fainter
stars, and/or perfom the photometry of bright stars with more precision than a simple camera.

To detect exoplanets one needs both large samples of stars recorded as continuously as
possible over several years and high precision photometry. Besides being cheap, the advantage
of a small camera is than the field is larger. But with a larger telescope in space like Kepler one
can target regions of the sky with density of stars optimal for the CCD/camera combination, and
observe continuously for months with the same instruments, which is crucial for differential
photometry. Thousands of amateurs worldwide detecting as many new exoplantes as Kepler
would face the problem of coordinating the analysis of huge amounts of heterogeneous and
incomplete data (due to day/night and weather interruptions in differently dark and transparent skies).

The real question is wether crowdsourcing planet detection is cheaper for global economy at equal scientific return than with state sponsored research. Perhaps the most important benefit of such an
activity is educational and promotional for research in general.

   

Comment Re:Lua[0]? (Score 1) 729

The discussion is not on measuring continuous quantities
  but counting discrete objects. Physicists and mathematicians have indexed, say, vectors, starting with 1 for ages, except in recent times where sometimes they use 0 for very special reason (like chapter 0 in a book).

The only difference between a car salesman and a computer salesman is that the car salesman knows he's lying.

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