FA-55463 / Astronomical coordinate conventions / Member archive

Solar disk image basis: Solar disk north is normalized by diameter instead of radius · case 03

The adapter reports an incorrect normalized north while other fields remain valid.

Member previewVariant 3 · 3 implementations · 6 checks per implementation

Case contract

A solar disk image supplies pixel displacements dx,dy, angular plate scale a, observer distance D, solar radius R, and exact supplied sine/cosine c,s of a position angle. Helioprojective east/north is the image rotation; normalized disk coordinates divide by angular radius R/D. Values are reduced linear-angle units. Output fields are defined by: helioprojective_east = d['a']*(d['c']*d['dx']-d['s']*d['dy']); helioprojective_north = d['a']*(d['s']*d['dx']+d['c']*d['dy']); angular_radius = d['R']/d['D']; normalized_east = d['a']*(d['c']*d['dx']-d['s']*d['dy'])*d['D']/d['R']; normalized_north = d['a']*(d['s']*d['dx']+d['c']*d['dy'])*d['D']/d['R']; disk_pixel_radius = abs(d['R']/d['D']/d['a'])

Why this case matters

Catalog, detector, sky-coordinate, and spectroscopy adapters must preserve the association between numeric coordinates and their declared reference conventions.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
astronomical fixture 0	`{"angular_radius": 0.4, "disk_pixel_radius": 0.2, "helioprojective_east": -10, "helioprojective_north": 10, "normalized_east": -25.0, "normalized_north": 12.5}`	`{"angular_radius": 0.4, "disk_pixel_radius": 0.2, "helioprojective_east": -10, "helioprojective_north": 10, "normalized_east": -25.0, "normalized_north": 25.0}`	Failed

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