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  • two_handfuls 1 hours

    This sounds like the "hmm this is strange" first step of discovery.

    metalman 32 minutes

    cue:ominous creapy alien sound track .play

  • superkuh 3 hours

    It's well known that higher solar wind/CMEs density/speed/etc that comes with the peak of the 11 year intensity cycles scatters cosmic rays before they enter the inner heliosphere. Combine this with the 1~3 years it takes for the solar wind to travel out through the heliosphere and you get the phase difference. Really cool unintended sensor empirical data on it though.

    Don't try to correlate with the sun spots, correlate with the solar wind/cmes from the spots getting out far enough to effectively scatter the incoming cosmic rays away.

    3lambda 2 hours

    I thought it only takes a few days for solar wind to travel from the sun to the Earth? Can you clarify?

    terminalbraid 3 hours

    The paper claims directly "the rate of degradation over time remains unsatisfactorily unpredictable" but you are claiming the authors do not understand or are unaware of the point you are making?

    superkuh 2 hours

    I think what I explained is known by anyone in solar physics. I cannot believe they would not have discussed it. It's absence in the paper is weird. But I think unpredictable refers more to LEO in the context of the paper where things are indeed more dynamic that just the 11 year periodicity of cosmic rays from solar activity causing scattering in the heliosphere.

    DANmode 2 hours

    Identifying a mechanism is not predicting its rate.

    There may be another variable they’re trying to pin down.

  • ck2 3 hours

    you should see what cosmic rays do to space telescopes

    public almost never sees what raw images look like

    RAW https://blog.galaxyzoo.org/wp-content/uploads/2010/04/spiral...

    FINAL https://blog.galaxyzoo.org/wp-content/uploads/2010/04/spiral...

    * https://blog.galaxyzoo.org/2010/04/12/how-to-handle-hubble-i...

    they also slowly destroy the sensors since they are physical particles moving at almost the speed of light

    plmpsu 2 hours

    Oh wow, I thought those were stars at first.

    2 hours

    r_lee 2 hours

    thanks for the links, that's really interesting to look at

    do you happen to know how exactly those artifacts are cleaned up?

    lofaszvanitt 2 hours

    photoshop ;D, or using multiple pictures

    icegreentea2 1 hours

    The blog link describes the cleanup process.

    They take two pictures, each taking up half the total observation period. If you subtract the two images, the deltas should be the cosmic ray flashes. You can then subtract those out. They use two pictures as opposed to more to minimize the impact of readout noise.

    To deal with "stuck pixel" type errors, they can slightly shift the camera between the two observations. They can counter act the shift before doing the initial subtraction.

    javier2 1 hours

    its actually quite doable. any cosmic rays will not be present in two pictures in a row. any permanent damage will be exactly the same in all pictures.

    shrubble 2 hours

    One way is to take a “blank” picture which will then show just the noise; then use that as a reference for what can be removed from the image.

    rbanffy 2 hours

    The blank should only show long term damage. Hits while the sensor is collecting light can be averaged out from multiple readings of the sensor.

    netsharc 2 hours

    Reminds me of the radiation after Chernobyl causing flashes on the physical film: https://www.youtube.com/watch?v=KOLBEx5DBaE

    jurebb 1 hours

    thank you so much for this link! I have been trying to search for footage of this phenomenon (in the pre-llm era) 10+y ago

    adonovan 36 minutes

    Can anyone tell whether these exposures occurred through the camera lens (from fallout particles in the sky of the depicted scenes) or in post- (or pre-) exposure handling of the film from hot dust carried by the photographer?

    matherial 25 minutes

    There's no reason they would preferentially travel through the lens and hit the current frame because most of the camera and film housing is about as transparent to gamma radiation as glass. Or maybe more transparent, because glass lenses in pro cameras tend to be rather bulky.

    So this just happened somewhere between arrival to and departure from the zone.