
An amateur astronomer became one of history’s greatest solar observers (2017) - Hooke
https://www.atlasobscura.com/articles/sunspots-japanese-amateur-astronomer-sun-science
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mturmon
What a nice article, that touches on a couple of issues in solar physics:

o Because you have a big object, and a lot of photons, it's possible for
amateur or less-equipped astronomers/departments to make a significant
contribution. You can do a lot with a sub-1m telescope in a good location.

o The solar cycle is 11 years, so in the career of a solar physicist, they
might see 3 full solar cycles. You might work for a decade to get an
instrument in orbit to observe, and see a solar cycle that is kind of
underwhelming (like the just-ended solar cycle 24).

o Given the above (time scale of instruments vs. Sun), there is a hard inter-
calibration problem of _critical_ time series like activity or irradiance. You
need to keep consistent daily measurements over decadal time scales. This
timebase spans the observing lifetime of telescopes, people, and even groups
of people -- university groups come and go over a 30-year time span.

Sunspot and active region determination is automated now, of course -- but
this kind of historical record is really important. And, just because it's
automated for one instrument, does not mean this carries over to the next one
with different spatial resolution and spectral/temporal sampling.

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ABeeSea
Reminds me of how Kepler made his infamous discovery of elliptic orbits by
staring at the data collected by his mentor Tycho Brahe. Without 20 years of
detailed observations and calculations, Kepler probably would have either
never come up with his theory or never have it taken seriously.

And of course Newton’s principia devotes large portions to proving Kepler’s
laws using Newton’s laws.

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thechao
Here are the first (1947) and last (1996) observations that are digitized. The
last, one the spots are very faint, in the lower-right-hand side of the Sun.

1\.
[https://www.kahaku.go.jp/research/db/science_engineering/sun...](https://www.kahaku.go.jp/research/db/science_engineering/sunspot/sketch/47/2kimg/s2k_j_470122.jpg)

2\.
[https://www.kahaku.go.jp/research/db/science_engineering/sun...](https://www.kahaku.go.jp/research/db/science_engineering/sunspot/sketch/96/2kimg/s2k_j_961231.jpg)

~~~
mturmon
Here is a movie of automatically-identified active regions covering 1996, as a
comparative:

[http://jsoc.stanford.edu/data/mdi/mdi-tarp/mdi-browse/ql-
mta...](http://jsoc.stanford.edu/data/mdi/mdi-tarp/mdi-browse/ql-
mtarp/harp.mdi.fd_Marmask_1996.114_TAI_253d_mask.mp4)

This movie was made from the science data products, but it's just a browse
product for convenience. See also:

[http://jsoc.stanford.edu/data/mdi/mdi-tarp/mdi-
synoptic/](http://jsoc.stanford.edu/data/mdi/mdi-tarp/mdi-synoptic/)

1996/12/31 is in Carrington Rotation number 1917.

