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comment by user-inactivated
user-inactivated  ·  2455 days ago  ·  link  ·    ·  parent  ·  post: The Worsening Cosmic Ray Situation

Happens every 11 or so years. We are now seeing the impacts of a potential geomagnetic flip, the first one in 700K years or so. With a weaker field there will be more cosmic ray strikes on the upper atmosphere. This makes me wonder if they are going to have to re-calibrate the C14 baselines for radiocarbon dating. Also, if the geomagnetic field is weakening are there going to be impacts on the health of astronauts in low earth orbit? are new satellites going to need extra radiation hardening? Is this going to puff up the stratosphere and mesosphere layers of the atmosphere and help deorbit some of the bits of space junk in orbit? The last solar maximum did squat for helping the space garbage problems after all.





rrrrr  ·  2454 days ago  ·  link  ·  

It's not just the usual 11-year cycle. As the article explains, the solar shield is weakening so that the maxima and minima of the cycle are lower than they were a few decades ago (see the first graph in the article). This means that more radiation reaches the Earth's own magnetic shield at each point in the cycle compared to the same point in the cycle in previous decades. And that effect will be compounded by the weakening of the Earth's own magnetic field. So for a number of reasons we're all getting higher doses these days.

The article doesn't say anything about why solar activity is weakening. So it seems this could just be a temporary fluctuation. The article's first graph shows that there was a weak cycle peaking around 1970 too, then it got stronger and recently weaker again. Are there studies of longer trends? And is there any understanding of the causes inside the sun? The small window of data shown in the article doesn't seem an adequate basis for prediction beyond the next few years.

user-inactivated  ·  2454 days ago  ·  link  ·  

    It's not just the usual 11-year cycle.

One thing that you have to understand reading an article like this is that we have been measuring cosmic ray impacts on the earth's atmosphere for fewer than 50 years. In the general scheme of things, that is nothing. If the sun has a 200 year cycle of magnetic pulses, we have not seen but a quarter of the cycle.

There has been an uptick of "OMG MAGNETIC FIELD DOOOOOM FLIPS!!!" lately. Since there was not a mass extinction, or even any long term damage to the planet from the last flip, we as biological critters are going to probably be fine. Our tech is going to have a rough time, but tech exists because smart people solved problems and came up with solutions to expected difficulties. Since these problems are solvable, I'm not worried about them per se. We are talking more hardening of orbital satellites and resources, requiring more launches (Thank you SpaceX) and heavier manned capsules and living quarters to compensate for the changing radiation environment.

Dala  ·  2453 days ago  ·  link  ·  

I wonder if extra shielding on our craft would do much good. Cosmic rays are believed to be the cause behind the Light Flash Phenomenon and at least one astronaut reported attempting to further shield himself behind lead batteries to no avail. This issue is believed to be increasing the incidence of cataracts in astronauts as well: https://science.nasa.gov/science-news/science-at-nasa/2004/22oct_cataracts

user-inactivated  ·  2452 days ago  ·  link  ·  

::Pfft:: What do a bunch of space nerds at NASA know? Everyone knows cosmic rays give you super powers.