Ten-trillionths of your suntan comes from intergalactic photons Astronomers led by the International Centre for Radio Astronomy Research (ICRAR) in Australia have calculated that ten trillionths of your suntan comes from beyond our local galaxy. Professor Simon Driver, lead author of the research, published today in The Astrophysical Journal, said that each square metre of the Earth is …
Well, each square meter facing the Sun, that is. Which is still 250,036,000 km2.
So that's 2,550,360,000,000,000,000,000,000,000,000,000 photons per second that are bouncing off Earth's surface.
Yikes.
Nuclear fusion is where its at baby. Still blows my mind the average energy output per mass unit isn't much greater than a lizard's energy output (when averaged over whole sun). The Sun however makes it up on the number of units of mass (though of course a small minority of the Sun is producing the vast majority of the energy).
Minor point: it's each square metre perpendicular to the sun, and many of those 250 million square kilometres are tilted away at some angle. Rather than use half the surface area of a sphere (2pi * r^2), use the cross-sectional area of the earth (pi * r^2). So it's 1.27 x 10^33 photons/second, half the result you got.
"But don’t worry, although energetic intergalactic photons - at micron wavelengths - can be damaging, you'll need to bathe in the warmth for trillions of years before they inflict long lasting damage. Solar photons are more dangerous as they make up a larger proportion."
But if your atoms in your body are effectively replaced every 7 years (G.C.S.E Biology in the earliest years so this might be wrong), does this mean that it isn't a problem?*
*looking past the obvious of near as dammit immortality not yet attainable
First time I've heard the inverse square law described as that...
Same applies if you're big boned. Applying the Journalistic Ignorance of Physics principle, you can see that if a hambeast has twice the surface area as a non-hambest, the exposure will be halved, because we all get the same photonic exposure.
Or something like that.
"The study is part of ICRAR’s aim to understand exactly how atoms in the early universe clumped together to form molecules and eventually whole galaxies."
Duh, someone didn't follow the instructions on the packet and didn't stir the mix properly*. So naturally it clumped.
* Seven times clockwise, one time anti-clockwise, repeat.
Half of the ultraviolet photons coming from other galaxies are also made less harmful as they bump into the dust grains, losing energy in the process.
Imagine tirelessly travelling all that intergalactic distance -- millions upon millions of light years -- only to get knackered by bouncing off a speck of dust before reaching anywhere interesting. Poor photons.
But don’t worry, although energetic intergalactic photons - at micron wavelengths - can be damaging, you'll need to bathe in the warmth for trillions of years before they inflict long lasting damage.
"An experiment was carried out to determine the harmfulness of intergalactic photons.
Step 1) A volunteer human being was placed in an environment with exposure to the photons,
Step 2) The condition of the volunteer was checked after 2.0 trillion years,
Step 3) The volunteer was found to be very dead.
Conclusion: intergalactic photons are very harmful to humans over the trillion-year scale. Also, based on further experiments of the same methd, we can confidently state the same is empirically true of: oxygen, Labrador puppies, honey, and soft fluffy pillows."
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