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Measuring Solar UV on earth ?

  1. Jun 4, 2015 #1
    Is solar uv completely blocked from reaching earth or do we just need more sensitive uv detectors to make ground-based observations? In particular of the uv wavelengths corresponding to hydrogen Lyman series lines.
  2. jcsd
  3. Jun 4, 2015 #2


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    Sunburns offer compelling evidence that some fraction of solar UV does reach the ground. The atmosphere screens out most, but not all UV radiation. I suspect some radiation at these wavelengths is visible in the Lyman series, but, most is in the Balmer series.
  4. Jun 4, 2015 #3
    Thanks - the reason I asked because we've got a whole lot of fancy hardware up in space examining distant stars and galaxies yet the data on our very own special star, the sun is pretty woeful as far as I can make out. I have researched sources of solar Lyman Alpha and Lyman Beta profiles and so far the best I can find is Artzner's 1978 profile and Lyman Beta extracted via 'densitometry' from Tousey's early rocket based observations. I would like to see Artzner's very careful profile at higher resolution. I would like to see what's going on in the small dips you see in left and right peaks. I would like to have a precision measurement of a key reference wavelength namely the geo-coronal absorption rather than seeing attempts to whitewash it out of the picture possibly compromising the profiles. I would also like to see precision measurements on the separation of the peaks in these profiles. Does that vary? Should it vary ? Do we need to be very careful where we measure (ie at disk centre of "quiet sun" rather than in wavy limb filaments or whatever) ?
  5. Jun 4, 2015 #4


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    If you're not too clear on how UV radiation affects the earth and things living on the surface, you should peruse these fact sheets from the US EPA:


    After all, sun tans do not come solely out of a bottle.
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