6 ms·

Kepler's 400-year-old sunspot sketches helped solve a modern mystery

110 points by benbreen 2y ago

itsaboutspots 2y ago
[flagged]
deleted 2y ago
[deleted]
dylan604 2y ago
I'm constantly amazed at these historical records still exist. Kepler's et al are one thing, but some of the much older from China are also impressive that the information exists today and is still somehow accessible. Now that everything is digital, will they still be available in the future to the same extent that these older analog records have been
- efdee 2y ago
  I think that yes, they will. Generally these historical records exist because some people went through the effort of preserving them for all these years. I feel this effort is a lot lower when your records are digital and infinitely duplicatable.
  - pleb_nz 2y ago
    But are digital records really more resilient to catastrophic societal and global changes? Physical records don’t need anything to exist and be read and only time and simple resources to duplicate compared with digital.
    - stouset 2y ago
      > Physical records don’t need anything to exist and be read Surely you’re joking. Physical records are notoriously fragile. They default to having a single copy and require intentional effort to create and distribute duplicates. They are frequently lost to fires, fading, physical decay, and even just being misplaced for generations. Digital records have their own issues, but implying with a straight face that the default state of physical records is persistence is a bridge too far.
      - dylan604 2y ago
        We have analog records from thousands of years ago, and we still have the technology to use them. I have digital formats from ~25 years ago that can no longer be read. I think the longevity speaks for itself. Water and fire are equally destructive to digital or analog. Library of Congress has chosen analog vinyl for long term storage over any digital format. I think you're putting way too much faith in digital and totally discounting analog.
        jwells89 2y ago
        It would make a lot of sense to develop some kind of digital storage medium that’s reasonably easy/cheap to read and write and is designed to endure centuries and hopefully millennia. Of course, this would need to come alongside a reader device which is similarly durable to ensure effectiveness (archives that can’t be read might as well not exist), which I suspect is the greater challenge.
        dylan604 2y ago
        except anything you can build today will be slow and tiny capacity tomorrow. the fact that anyone could suggest a universal format can be developed that will endure all of time where everyone continues to use it for ever after it is introduced is farcical like a fairy tale where unicorns exist.
        jwells89 2y ago
        I would imagine that the express purpose for this format would be exclusively ultra-long-term archival and that it would not see much if any day to day usage, similar to tape drives now (but on a much longer timeline). For this purpose speed and capacity aren't as important because we've had great information density for relatively small file sizes for a long time now. A ridiculous amount of information can be stored in just plain old text files, especially if compressed. For video and audio, recordings in even just 128k AAC and 720p h.264 video would be a wonderful thing to have 100+ years from now; anything better would be a cherry on top.
    - deleted 2y ago
      [deleted]
  - dylan604 2y ago
    Keeping a digital archive is much more expensive than an analog one. In 1990s, if you saved something to floppy, is it still accessible now? Oh, so a new format comes along, so you spend more money to migrate data from old and busted to new hotness format of today. Every time a new comes out? Every other new flavor? What about bit rot so when you try to migrate you've lost readability? Who is paying for all of these format migrations? The ancient Chinese scroll that a monk wrote noting a super novae from the first century is still operational.
    - Xen9 2y ago
      Hard drives are non-magnetic & remain readable with good microscope indefinitively. They ALSO allow one to use superior error correction algorithms at ease (analog EC being possible). There exists no obligation to "always mitigate." Actually, from your comment it follows that one should not mitigate constantly. For large archives, volume determines the cost, because the archive needs to be maintained at constant temprature, humidity etc. Digital storage, being much more dense, costs less. Architecturally, this will also mean that the further distance between points A and B in the digital archive will grow, I would claim roughly exponentially, slower than what happens in the analog archive. This will affect the costs in myriad ways, which I at the time of writing don't recall.
      - lgats 2y ago
        I think you mean CDs/DVDs are non magnetic and can be read with a microscope.
        Xen9 2y ago
        Perhaps I was wrong, thanks.
        adrian_b 2y ago
        The CDs/DVDs use a metallic mirror. With the exception of certain expensive CDs made for archival purposes, e.g. by Kodak, which used a gold mirror, the reflective layer can oxidize in time, becoming transparent, when it no longer reflects the light. The pressed CD-ROMs/DVD-ROMs still have pits in the polycarbonate disc, even when the mirror is no longer reflective. Those could still be read with a more sophisticated microscope, e.g. by using phase contrast. The recordable CD-Rs/DVD-Rs used an organic dye for storing the bits and after a long enough time that dye can be completely degraded and it can become impossile to read. The rewritable CD-RWs/DVD-RWs store the bits in a layer that can be either amorphous or crystalline, with different reflectivities. After a long enough time, that layer can recrystallize, erasing the bits. Of all the optical discs that have been available commercially, those with the longest archival time were the pressed CD-ROM with gold mirrors, where the only degradation mechanism is the depolymerization of the polycarbonate, which could make them fragile, but when kept at reasonable temperatures and humidities that should require many centuries. There have been experiments with write-once optical memories where the bits are stored in an inorganic glass that should easily last for many millennia, but until now I have not heard of commercial products. In any case, none exist at an affordable price.
- Terr_ 2y ago
  You might enjoy the oldest active financial bond, a parchment manuscript from the Dutch water authority 1624. It still pays a small amount of interest (a bit over 13 Euros per year) provided that the bearer (currently the New York Stock Exchange) if they show up every few years to collect it.
  - addaon 2y ago
    Thanks, I did: https://www.npr.org/2023/11/17/1213684464/worlds-oldest-bond-is-gearing-up-for-its-400th-birthday-its-still-paying-interes https://www.npr.org/2023/11/17/1213684464/worlds-oldest-bond...
- gwervc 2y ago
  It helped that the written language was modeled on an earlier variation and stayed relatively stable over millennia. I was amazed yesterday that I could understand a bit of a poem written about thousand years ago, and that the poem references a poet that lived another thousand years ago at the time of writing.
ohthehugemanate 2y ago
I am curious about the methods used by these early astronomers. TFA mentions Chinese astronomers observing sunspots in the third century BCE. How? Did they use a camera obscura, too? It also casually mentions "reconstructions based on tree rings." What? How do tree rings tell us about sunspot activity cycles?
- goodcanadian 2y ago
  What? How do tree rings tell us about sunspot activity cycles? IIRC, solar activity affects the level of charged particles hitting the upper atmosphere which in turn, affects the ratios of radioactive elements in the atmosphere. Traces of these variations can be found in the wood of trees that grew at the time. The tree rings provides dates for the growth.
  - adtac 2y ago
    Are there enough trees from 300 BCE that still survive today? In the ones that do, wouldn't there be enough thermodynamic diffusion within the tree trunk to obfuscate the true isotope levels in each ring?
- zavec 2y ago
  It also mentions telescope observations, did those go to a camera obscura after going through the telescope (is that possible?) or were people actually just staring at the sun through a telescope? How did they not go blind?
aussieguy1234 2y ago
This group of sunspots triggered a large solar storm and a strong aurora. For comparison, the Carrington event was said to have a strength of -800nt to -1400nt (the more negative the number, the stronger the storm). The storms on May 11th were verified to have reached -800nt, so right at the bottom of the Carrington event estimates. Interestingly, while there were a few minor easily fixed issues, the world as we know it did not end as some have said it would with a Carrington scale event.

110 points by benbreen 2y ago

itsaboutspots 2y ago

[flagged]

deleted 2y ago

[deleted]

dylan604 2y ago

I'm constantly amazed at these historical records still exist. Kepler's et al are one thing, but some of the much older from China are also impressive that the information exists today and is still somehow accessible. Now that everything is digital, will they still be available in the future to the same extent that these older analog records have been

efdee 2y ago
I think that yes, they will. Generally these historical records exist because some people went through the effort of preserving them for all these years. I feel this effort is a lot lower when your records are digital and infinitely duplicatable.
- pleb_nz 2y ago
  But are digital records really more resilient to catastrophic societal and global changes? Physical records don’t need anything to exist and be read and only time and simple resources to duplicate compared with digital.
  - stouset 2y ago
    > Physical records don’t need anything to exist and be read Surely you’re joking. Physical records are notoriously fragile. They default to having a single copy and require intentional effort to create and distribute duplicates. They are frequently lost to fires, fading, physical decay, and even just being misplaced for generations. Digital records have their own issues, but implying with a straight face that the default state of physical records is persistence is a bridge too far.
    - dylan604 2y ago
      We have analog records from thousands of years ago, and we still have the technology to use them. I have digital formats from ~25 years ago that can no longer be read. I think the longevity speaks for itself. Water and fire are equally destructive to digital or analog. Library of Congress has chosen analog vinyl for long term storage over any digital format. I think you're putting way too much faith in digital and totally discounting analog.
      - jwells89 2y ago
        It would make a lot of sense to develop some kind of digital storage medium that’s reasonably easy/cheap to read and write and is designed to endure centuries and hopefully millennia. Of course, this would need to come alongside a reader device which is similarly durable to ensure effectiveness (archives that can’t be read might as well not exist), which I suspect is the greater challenge.
        dylan604 2y ago
        except anything you can build today will be slow and tiny capacity tomorrow. the fact that anyone could suggest a universal format can be developed that will endure all of time where everyone continues to use it for ever after it is introduced is farcical like a fairy tale where unicorns exist.
        jwells89 2y ago
        I would imagine that the express purpose for this format would be exclusively ultra-long-term archival and that it would not see much if any day to day usage, similar to tape drives now (but on a much longer timeline). For this purpose speed and capacity aren't as important because we've had great information density for relatively small file sizes for a long time now. A ridiculous amount of information can be stored in just plain old text files, especially if compressed. For video and audio, recordings in even just 128k AAC and 720p h.264 video would be a wonderful thing to have 100+ years from now; anything better would be a cherry on top.
  - deleted 2y ago
    [deleted]
- dylan604 2y ago
  Keeping a digital archive is much more expensive than an analog one. In 1990s, if you saved something to floppy, is it still accessible now? Oh, so a new format comes along, so you spend more money to migrate data from old and busted to new hotness format of today. Every time a new comes out? Every other new flavor? What about bit rot so when you try to migrate you've lost readability? Who is paying for all of these format migrations? The ancient Chinese scroll that a monk wrote noting a super novae from the first century is still operational.
  - Xen9 2y ago
    Hard drives are non-magnetic & remain readable with good microscope indefinitively. They ALSO allow one to use superior error correction algorithms at ease (analog EC being possible). There exists no obligation to "always mitigate." Actually, from your comment it follows that one should not mitigate constantly. For large archives, volume determines the cost, because the archive needs to be maintained at constant temprature, humidity etc. Digital storage, being much more dense, costs less. Architecturally, this will also mean that the further distance between points A and B in the digital archive will grow, I would claim roughly exponentially, slower than what happens in the analog archive. This will affect the costs in myriad ways, which I at the time of writing don't recall.
    - lgats 2y ago
      I think you mean CDs/DVDs are non magnetic and can be read with a microscope.
      - Xen9 2y ago
        Perhaps I was wrong, thanks.
        adrian_b 2y ago
        The CDs/DVDs use a metallic mirror. With the exception of certain expensive CDs made for archival purposes, e.g. by Kodak, which used a gold mirror, the reflective layer can oxidize in time, becoming transparent, when it no longer reflects the light. The pressed CD-ROMs/DVD-ROMs still have pits in the polycarbonate disc, even when the mirror is no longer reflective. Those could still be read with a more sophisticated microscope, e.g. by using phase contrast. The recordable CD-Rs/DVD-Rs used an organic dye for storing the bits and after a long enough time that dye can be completely degraded and it can become impossile to read. The rewritable CD-RWs/DVD-RWs store the bits in a layer that can be either amorphous or crystalline, with different reflectivities. After a long enough time, that layer can recrystallize, erasing the bits. Of all the optical discs that have been available commercially, those with the longest archival time were the pressed CD-ROM with gold mirrors, where the only degradation mechanism is the depolymerization of the polycarbonate, which could make them fragile, but when kept at reasonable temperatures and humidities that should require many centuries. There have been experiments with write-once optical memories where the bits are stored in an inorganic glass that should easily last for many millennia, but until now I have not heard of commercial products. In any case, none exist at an affordable price.
Terr_ 2y ago
You might enjoy the oldest active financial bond, a parchment manuscript from the Dutch water authority 1624. It still pays a small amount of interest (a bit over 13 Euros per year) provided that the bearer (currently the New York Stock Exchange) if they show up every few years to collect it.
- addaon 2y ago
  Thanks, I did: https://www.npr.org/2023/11/17/1213684464/worlds-oldest-bond-is-gearing-up-for-its-400th-birthday-its-still-paying-interes https://www.npr.org/2023/11/17/1213684464/worlds-oldest-bond...
gwervc 2y ago
It helped that the written language was modeled on an earlier variation and stayed relatively stable over millennia. I was amazed yesterday that I could understand a bit of a poem written about thousand years ago, and that the poem references a poet that lived another thousand years ago at the time of writing.

ohthehugemanate 2y ago

I am curious about the methods used by these early astronomers. TFA mentions Chinese astronomers observing sunspots in the third century BCE. How? Did they use a camera obscura, too? It also casually mentions "reconstructions based on tree rings." What? How do tree rings tell us about sunspot activity cycles?

goodcanadian 2y ago
What? How do tree rings tell us about sunspot activity cycles? IIRC, solar activity affects the level of charged particles hitting the upper atmosphere which in turn, affects the ratios of radioactive elements in the atmosphere. Traces of these variations can be found in the wood of trees that grew at the time. The tree rings provides dates for the growth.
- adtac 2y ago
  Are there enough trees from 300 BCE that still survive today? In the ones that do, wouldn't there be enough thermodynamic diffusion within the tree trunk to obfuscate the true isotope levels in each ring?
zavec 2y ago
It also mentions telescope observations, did those go to a camera obscura after going through the telescope (is that possible?) or were people actually just staring at the sun through a telescope? How did they not go blind?

aussieguy1234 2y ago

This group of sunspots triggered a large solar storm and a strong aurora. For comparison, the Carrington event was said to have a strength of -800nt to -1400nt (the more negative the number, the stronger the storm). The storms on May 11th were verified to have reached -800nt, so right at the bottom of the Carrington event estimates. Interestingly, while there were a few minor easily fixed issues, the world as we know it did not end as some have said it would with a Carrington scale event.