Print Earth's inclination as 0.00 degrees, not -0.00

Standish's Table 2a fits the Earth-Moon barycentre's inclination as -0.00054346 degrees, and the
card printed toFixed(2) of it: "Inclination -0.00°", where the branch's base read 0.00. A negative
inclination is the same orbit as its size with the node turned half round, so the card prints the
size. The elements the map propagates are left as Standish gives them. The live Earth page now
reads "INCLINATION 0.00°".

Control: printing the fitted sign again fails "prints the size of an inclination fitted below
zero".

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-09-29 19:11:56 +02:00
co-authored by Claude Opus 5.5
parent 395b613f82
commit 86d97b903e
2 changed files with 9 additions and 1 deletions
@@ -68,6 +68,12 @@ describe('buildBodyViewModel', () => {
expect(model?.orbitalPeriodDays).toBeCloseTo(27.32166, 5);
});
it('prints the size of an inclination fitted below zero, as the same orbit with its node turned half round', () => {
const tilted: BodyRecord = { ...earth, orbit: orbit({ inclinationDeg: -0.00054346 }) };
const model = buildBodyViewModel('earth', { ...catalogues, bodies: [tilted] })!;
expect(bodyReadouts(model).measured.find((row) => row.label === 'Inclination')?.value).toBe('0.00°');
});
it('says where the orbit comes from, in the card’s provenance', () => {
expect(bodyReadouts(buildBodyViewModel('luna', catalogues)!).provenance).toContain('Orbit: JPL SSD satellite mean elements, epoch 2000 Jan 1.');
});