Remote imaging, processing pipeline, and observing plans. Merged from itelescope + astro-pipeline.
laurence
3f785136ed
Rule 2 of the workflow is that state lives in the repo rather than the chat, and a long session had put most of the current position only in the chat. This writes it down. TODO.md gains a RESUME HERE block at the top, because the useful question for the next session is not what has been done but what to do next and what is blocking it. It names the three live strands, the three decisions waiting on the user, and the one thing that will break the batch run if it is forgotten: NGC 6744 mixes bin1 luminance at 4096x4096 with bin2 colour at 2048x2048, so registration has to resample onto a common grid. Nothing else in the archive does that, which is exactly why it will be forgotten. It also drops three duplicate "Done (recent)" headings that had accumulated, and tabulates what the five archived sessions actually contain. NOTES.md gains the gotchas, all of which produced plausible wrong answers rather than errors: every frame is delivered twice as calibrated and raw, so extracting both silently doubles the stack; an interrupted segmented download leaves DIRECTORIES named like files, which defeats anything that trusts an extension; a re-mirror duplicates rather than replaces; two T20 archives are genuinely corrupt; extraction triples the disk footprint and filled the drive. Alongside them the analysis lessons from NGC 5128, kept for the same reason - each is a way to be confidently wrong. DECISIONS.md records why the pipeline reads headers rather than filenames, and why imaging is being made push-button while the science stays hand-driven. ARCHITECTURE.md described a documentation-only repository with no code, which stopped being true when the pipeline merged in. It now covers all three parts, the code-and-data separation the pipeline is built around, and the on-disk session layout. Both of this session's own errors are recorded in TODO.md as things not to repeat: measuring a foreground star instead of the galaxy nucleus and booking telescope time to fix it, and telling the user NGC 6744 had not been processed when it had. |
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|---|---|---|
| docs | ||
| itelescope | ||
| observing/eclipse-2026-menorca | ||
| pipeline | ||
| state | ||
| .gitignore | ||
| CLAUDE.md | ||
| README.md | ||
astrophotography
Everything to do with taking, processing and understanding astronomical images: the remote telescopes, the code that turns their frames into pictures and measurements, and the plans for observing in person.
Formed by merging the itelescope and astro-pipeline repositories, with the
history of both preserved.
Layout
| Directory | What it is |
|---|---|
| itelescope/ | The iTelescope.net remote telescope network: a review of every scope, a southern-target guide, the observing plans, and the points drain campaign |
| pipeline/ | The processing and analysis code. Calibration, stacking, plate solving, rendering and the science analyses |
| observing/ | Plans for observing in person. Currently the total solar eclipse of 12 August 2026 from Menorca |
| state/ | Project state under the Default Workflow: objective, current work, decisions, working notes |
| docs/ | The Default Workflow itself: branching, commits, documentation policy, cost control |
Start here
- Planning or reviewing a remote imaging run: itelescope/CAMPAIGN.md and itelescope/TELESCOPES.md
- Processing a session's data: pipeline/README.md
- What is happening right now: state/TODO.md
- Why something was done a particular way: state/DECISIONS.md
Where the image data lives
Not in this repository. A single calibrated frame is 61 MB and a session
runs to several gigabytes, so sessions stay on disk and the code finds them
through the ASTRO_SESSION environment variable:
set ASTRO_SESSION=...\NGC5128\20260721
python pipeline/stack.py
Each session directory carries its own METHODS.md describing what was done to
that data and what was found, written for a reader who was not there. The code
lives here; the pixels and the account of them live with the data.
Things learned the hard way
Recorded because each cost real time or real money, and because each is a requirement for anything built next rather than a curiosity:
- Measure whether a core is saturated before buying time to fix it. A foreground star 69 arcsec from Centaurus A's nucleus was mistaken for the galaxy, and a telescope booking was made to solve a problem that did not exist. Filter the stars out of the measurement first.
- Vet moving-object candidates in detector coordinates. Registration holds the sky still, so it drags sensor defects across the frame on perfectly straight, constant-rate tracks. Hot pixels are better-behaved asteroids than real asteroids. One cut took 141 confident spurious detections to zero.
- Never compare an aperture magnitude against a point-source catalogue without checking the source is a point. A resolved object looks exactly like a 2.8 magnitude outburst.
- Never fit a sky background to a field the target fills. A plane fitted around a large galaxy eats its halo, measured at -17.9 ADU/px. Fit the background and a source model together.
- A photographic ND filter is not a solar filter. It passes the infrared that carries the heat.