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.
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?
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.
If you carefully re-read what GP wrote, you'll see there's no reference to Earth's orbit or 1 AU in there. GP wrote about the solar wind scattering cosmic rays when it reached some point in its outward travel.
Coronal mass traveling at a higher speed "sweeps" what's before it. You can see the spiral shape, and you can probably figure out that the stuff is slowing down as it moves outward.
Watch this occasionally for a few months and you'll get the idea, although solar activity is slowing down somewhat (as expected).
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.
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.
Signal processing / denoising of astronomical images is a field of study onto itself.
If you are like me you will find it super interesting. There is immense variety based upon what kind of telescope, what do you want to capture, whether it's for science or astrophotography (aesthetics).
If you are into math side of things you can begin with Richardson-Lucy as a starting point and stacking.
I suppose I got lucky with the search terms on YouTube, I remember watching a documentary showing the first sight of the reactor filmed from a helicopter, and the narrator saying "The flashes of light on the footage are due to radiation". I was hoping to find this heli video on YouTube, but all the "chernobyl heli" footage are from the TV series, or very very low res. The video above isn't what I was looking for, but it shows the effects of radiation very well.
Sheesh, but DuckDuckGo and Google are quite useless. I just tried to see if The Internet has a record of the heli that flew to Chernobyl to shoot that first footage of the blown reactor (IIRC from Moscow, although that does not seems a plausible flying distance), and the search engines think I want to instead find out about the heli that crashed after hitting a crane...
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?
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.
They are not part of the image of the scene. They wouldn't be focused by the optics.
The optics would just be a slight attenuation much like the rest of the camera housing, film reel, operator, etc. So really a summation of all the exposure types you can imagine.
Seeing visible light flashes in the scintillator was one of oldest ways how we observed ionizing radiation. It's more then 100 years old method.
"This built upon the work of earlier researchers such as Antoine Henri Becquerel, who discovered radioactivity whilst working on the phosphorescence of uranium salts in 1896. Previously, scintillation events had to be laboriously detected by eye, using a spinthariscope (a simple microscope) to observe light flashes in the scintillator."
Is the relevant radiation solar radiation, or is there damage from radiation coming from the direction the optics are pointed? If it's the latter, then maybe the sun's emissions interact with inbound particles from sources outside the solar system? (I don't have sufficient background or time to check whether the paper already rules this out.)
There is a known reason for this (among radiation belt enthusiasts) that the authors either don't mention or don't know. Hubble's orbit is in the inner Van Allen belt, where the radiation intensity is out of phase with the solar cycle (because the atmosphere is thinner at solar minimum, and expands at solar maximum, affecting the inner radiation belt). See Figure 6 (https://agupubs.onlinelibrary.wiley.com/cms/asset/718954d6-3...) of this paper (https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JA02...). Hubble is in a low altitude, near equatorial orbit, so the red curve (small L) is the most relevant one.
superkuh | a day ago
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.
terminalbraid | a day ago
superkuh | a day ago
DANmode | a day ago
There may be another variable they’re trying to pin down.
3lambda | a day ago
aaron_m04 | a day ago
m3047 | a day ago
Watch this occasionally for a few months and you'll get the idea, although solar activity is slowing down somewhat (as expected).
https://www.spaceweather.gov/products/wsa-enlil-solar-wind-p...
ck2 | a day ago
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
r_lee | a day ago
do you happen to know how exactly those artifacts are cleaned up?
shrubble | a day ago
rbanffy | a day ago
lofaszvanitt | a day ago
javier2 | a day ago
icegreentea2 | a day ago
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.
empiricus | a day ago
empiricus | a day ago
srean | a day ago
If you are like me you will find it super interesting. There is immense variety based upon what kind of telescope, what do you want to capture, whether it's for science or astrophotography (aesthetics).
If you are into math side of things you can begin with Richardson-Lucy as a starting point and stacking.
netsharc | a day ago
jurebb | a day ago
netsharc | 20 hours ago
Sheesh, but DuckDuckGo and Google are quite useless. I just tried to see if The Internet has a record of the heli that flew to Chernobyl to shoot that first footage of the blown reactor (IIRC from Moscow, although that does not seems a plausible flying distance), and the search engines think I want to instead find out about the heli that crashed after hitting a crane...
adonovan | a day ago
matherial | a day ago
So this just happened somewhere between arrival to and departure from the zone.
saltcured | a day ago
The optics would just be a slight attenuation much like the rest of the camera housing, film reel, operator, etc. So really a summation of all the exposure types you can imagine.
CamperBob2 | a day ago
pantulis | 10 hours ago
flufluflufluffy | 9 hours ago
m3047 | a day ago
leonidasrup | a day ago
"This built upon the work of earlier researchers such as Antoine Henri Becquerel, who discovered radioactivity whilst working on the phosphorescence of uranium salts in 1896. Previously, scintillation events had to be laboriously detected by eye, using a spinthariscope (a simple microscope) to observe light flashes in the scintillator."
https://en.wikipedia.org/wiki/Scintillation_counter
plmpsu | a day ago
two_handfuls | a day ago
metalman | a day ago
jimrandomh | a day ago
gramie | a day ago
:-)
insane_dreamer | a day ago
AgentLemon | a day ago