
Observation of Cherenkov Light Generation in the Eye During Radiation Therapy - bookofjoe
https://www.redjournal.org/article/S0360-3016(19)33947-1/fulltext
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bookofjoe
Generation of Cherenkov Light Flashes by Cosmic Radiation within the Eyes of
the Apollo Astronauts (1970)

[https://www.nature.com/articles/228260a0](https://www.nature.com/articles/228260a0)

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dekhn
When I was a postdoc at berkeley I was talking to a professor (chair of my
department) and he said he had done some research on this problem (if you
watch the movie Right Stuff, one of the guys who goes to space may experience
this due to cosmic gamma rays).

The professor said something that I still think is audacious. He wanted to
resolve the issue, but couldn't get IRB approval to run experiments on
students, so he experimented on himself. By looking into a synchrotron.
Synchrotrons are some of the most powerful lights humans make, with broad
spectrum and extremely high intensities.

He said he did a bunch of calculations to come up with filters to ensure that
statistically a very small number of photons with specific energies entered
his eyeball. Installed those into the viewing platform on the synchrotron, and
opened the aperture with his eye in the light path.

I believe it's this paper (currently paywalled):
[https://www.nature.com/articles/230596a0](https://www.nature.com/articles/230596a0)
which should describe the experiment and the identity of the subject.

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bookofjoe
>Abstract Hypothesized that light flashes observed by astronauts in space are
caused by ionization or another form of interaction of primary cosmic
particles with tissues, and that "streaks may be heavy primaries, and double
points could be accounted for by 1 cosmic particle intersecting the retina at
2 points . . . . To test the validity of these hypotheses and the probability
that the human dark-adapted eye may be a sensitive and unique cosmic ray
detector," visual phophene phenomena produced by fast neutrons were
investigated using 2 human Ss. Ss "were exposed to a beam of fast neutrons
with energies between 20-640 MeV produced by a 0.64 GeV proton beam impinging
on a 12 cm beryllium target." Both Ss were dark adapted over 2 hr. before
exposure. After exposure, 1 S saw pinpoint flashes coinciding with the
presence of the beam; the other S saw between 25-50 bright discrete lights. In
another exposure in which the beam contained no protons or other particles,
there were no observations of visual phenomenon during or after a total
exposure of about 5,000 particles through each retina. X-ray phosphenes did
not produce visual phenomena similar to bright pinpoints of light observed
during neutron exposure. It is suggested that if the passage of "particles
causes irreversible deterioration of retinal cells and of neurons, then in a
long space flight outside the Earth's magnetosphere, a significant degree of
random cellular damage might result." (PsycINFO Database Record (c) 2016 APA,
all rights reserved)

source:
[https://psycnet.apa.org/record/1972-25998-001](https://psycnet.apa.org/record/1972-25998-001)

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im3w1l
That's really neat. But imagining higher than (material) speed of light
electrons zipping through my eyes is a bit unsettling.

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ravedave5
interesting! I believe I saw patterns during an MRI, it was really
interesting.

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sebazzz
MRI does not use radiation but magnetism instead. Are you not confusing CAT
instead?

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bob_sage
Fascinating!

