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Comment Supernovae as risk (Score 4, Interesting) 86

The research focuses on risks for life linked to cosmic radiation produced by supernovae (and massive stars in general).

This is only one of the risks. In dense regions of galaxies stars perturb the planetary orbits sufficiently frequently to destroy any climate stability. The solar system has been lucky not to have a star nearing the whole solar system in the last 4 billions years, such that even the outer planet orbits are near from circular.

On the other hand it is not difficult for life to screen strong cosmic radiation, such as
in the ocean and deep in the earth crust where most of the biomass exists. So the argument of cosmic radiation killing all life is probably wrong.

Comment Photons and solar wind (Score 4, Informative) 163

Since E=Mc^2 the whole earth gets 1.9 kg/s of sun's mass in the form of ultra-violet, and visible photons. But the earth recycles these photons to longer wavelengths and radiates slightly more mass/s in the form of infrared photons (the excess comes from the heat generated by radioactivity in rocks).

In addition the sun sends matter to Earth in the form of solar wind, mostly protons and electrons and a few helium nuclei send by the solar atmosphere. The average direct mass flux for the whole earth amounts to about 0.75 kg/s.

One could also think about the sun neutrino flux but most of these particles traverse the earth without stopping.

Comment Re:Neutrinos (Score 2) 191

Sorry, but the Standard Model predicts *massless neutrinos*, while oscillations found in experiments prove non-zero masses.
The extensions to the Standard Model that you mention could accommodate positive masses, but none of these is standard or unambiguously supported by experimental evidences yet.

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 Hypocrisy (Score 1) 81

So big companies corrupt politicians and organisations like FIFA, and nobody complains. Corruption flourishes because some entities propose money to people unable to say no. Both sides should be investigated by justice, but curiously little is done against big companies.

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. .

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