GH-3

Add example solar data from the AIA instrument on NASA's Solar Dynamics
Observatory (SDO) mission at low resolution (512x512).

General mission information:
* https://en.wikipedia.org/wiki/Solar_Dynamics_Observatory
* https://sdo.gsfc.nasa.gov/

Wavelength / spectral band information, and linking this back spatially
to the coronal region (height) and temperature:
* https://sdo.gsfc.nasa.gov/data/channels.php
* https://en.m.wikipedia.org/wiki/Solar_transition_region
* https://history.nasa.gov/SP-402/p2.htm

Specifics on images added:
* `wavelength_sequence`: a very short (~15 s) sequence of images across
   various wavelengths
   (does not include magnetogram data from the HMI instrument)
   * retrieved manually via https://sdo.gsfc.nasa.gov/assets/img/browse/
* `eruption_time_sequence`: a medium duration (~8 H) sequence of images
   (wavelength: 171 Angstroms: quiet corona, upper transition region).
   Show a small coronal mass ejection & some subsequent brightening
   nearby as the surrounding corona rearranges itself into a lower
   energy configuration, releasing energy in the form of minor flaring
   * retrieved via interface https://sdo.gsfc.nasa.gov/data/aiahmi/

GH-3

Download .jpg images from SDO using script based on solar rotation rate:
* used synodic solar rotation rate: 27.25 days
  * synodic: as seen from Earth - accounts for Earth's orbital motion
  * see https://www.star.bris.ac.uk/bjm/solar/solarrot.html
* rotation rate varies by solar heliolatitude
* synodic value above is valid for middling heliolatitudes ~26N (~26S)
  * faster near equator: ~24.27 days
  * slower near poles: ~35 days at very high heliolatitudes near pole
* value above almost matches rotation rate common in literature:
  * Carrington rotation rate: 27.26 days
* but 27.25 days used for convenience cf hours
  * allows cycles: T00, T06, T12, T18

Note images aren't calibrated
* so can't really compare images over these long gaps like used here
* dynamic range variation -> brightness varies between images
* better-calibrated source: get .fits data files from JSOC/other
  * e.g. via sunpy - see script comment

Images downloaded as follows:
```console
$ bin/download_sdo_data 2010-06-01 2023-10-01 0193 512 ~/open_source/spaceapps-2023-mo/data/immersed_sounds_space/SDO/solar_cycle_sequence/
[INFO] Tue 10 Oct 23:16:48 UTC 2023: downloading SDO images:
[INFO] * from 2010-06-01 to 2023-10-01
[INFO] * from AIA channel 0193 at resolution 512
[INFO] * to /net/home/h03/ehenley/open_source/spaceapps-2023-mo/data/immersed_sounds_space/SDO/solar_cycle_sequence
[INFO] (alternative images for each timestep are in /net/home/h03/ehenley/open_source/spaceapps-2023-mo/data/immersed_sounds_space/SDO/solar_cycle_sequence/alternatives)
[INFO] Downloading images from https://sdo.gsfc.nasa.gov/assets/img/browse/2010/06/01 matching 20100601_00[0-1]???_512_0193.jpg
[INFO] Downloading images from https://sdo.gsfc.nasa.gov/assets/img/browse/2010/06/28 matching 20100628_06[0-1]???_512_0193.jpg
<snip L9-L183>
[INFO] Downloading images from https://sdo.gsfc.nasa.gov/assets/img/browse/2023/08/15 matching 20230815_06[0-1]???_512_0193.jpg
[INFO] Downloading images from https://sdo.gsfc.nasa.gov/assets/img/browse/2023/09/11 matching 20230911_12[0-1]???_512_0193.jpg
[INFO]
[INFO] Wed 11 Oct 02:33:22 UTC 2023: download complete
```

GH-3

Update the download script & README
* mostly to expose image usage rules of road
* also to be explicit that script here is a derived work
  of original script from NASA
  * Upstream script does not have a clear licence
    * https://sdo.gsfc.nasa.gov/data/bestpractice.php
  * Assume not an issue, given intention (for data!) seems to be for reuse
    for precisely NASA Space Apps sort of usage:
    * https://sdo.gsfc.nasa.gov/data/rules.php

Also update README to:
* crosslink to the resources just added
* expose teams which chose spacewx-y challenges
* clarify the creche activities: 2024 might be able to do more here
* clarify the bootcamp stuff is to crosslink to last year's resources
  * this to keep institutional knowledge that these exists
  * again 2024 might be able to just reuse as pointers, even if don't
    rerun the bootcamp either

GH-3

Add top-level link so all teams can be discovered, not just spacewx ones!
Also add outputs for spacewx projects, to help discoverability

GH-3