Remote imaging, processing pipeline, and observing plans. Merged from itelescope + astro-pipeline.
Laurence
118dc36e92
The estate now runs Astrometry.net itself (ankh-morpork-infra astrometry/):
solve-field against ~5 GB of local index files, sized from this repo's
TELESCOPES.md so the whole iTelescope fleet's fields of view are covered.
blind.py now tries it before nova.astrometry.net. Speed is the least of the
reasons - a blind solve of a real DSS field returns in 0.7s where nova queues
for minutes. The reasons that matter are that nova requires UPLOADING the
master to a third party and holding an API key, and neither is necessary any
more for the ordinary case. nova remains the fallback, so an estate outage
costs speed and privacy rather than the ability to solve.
pipeline/astrometry_net.py is the client and nothing more: stdlib-only POST,
parses the returned .wcs so the full TAN solution is used rather than a
re-derivation from the summary numbers. It deliberately does NOT decide whether
to trust a solution - blind.py already verifies every blind solve against Gaia
and applies a star-count and residual gate, and two gates that can disagree is
worse than one that is trusted.
The source ('estate' or 'nova') is threaded through the log lines, the returned
method, and the ASTRSOLV card, because a year from now that card is the only
way to tell whether a frame was solved in-house or uploaded.
Also corrected astrometry.py's 'cannot solve without a blind solver' message,
which has been untrue since run.py started falling through to blind.py.
Tested against the live service: blind solve of a DSS2 field with a known
centre returned within ~4 arcsec in 0.7s; the WCS round-trips through astropy;
and an unreachable service falls through to nova instead of raising.
|
||
|---|---|---|
| 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.