A system was a handful of ellipses floating in the dark. You could see
that one orbit was bigger than another, but not how big, and not that a
planet sat above or below the plane the others share.
Adds the same plane-and-tether reading aid the outer scales got: a polar
grid in the system's own reference plane, with a drop line from each body
onto it.
Ring radii snap to a 1-2-5 ladder rather than dividing the system evenly,
because the point is to put a number on a distance — 5, 10, 15 AU can be
read at a glance and 4.34, 8.68, 13.02 cannot. That holds across the four
orders of magnitude real systems span: the solar system gets 5 AU rings,
TRAPPIST-1 gets 0.01 AU ones. The outermost ring encloses the outermost
orbit rather than falling just inside it.
The rings are dashed. Solid ones would sit in the same plane as the orbit
ellipses, which are themselves rings, and at a glance a reference circle
and a circular orbit are the same picture. Dashes are cut by dropping
whole segments rather than by a dashed material: the ring is already built
from independent segment pairs, so a material's dash pattern would restart
at every one.
Drawing the grid exposed a framing bug it made unmissable. The camera
settled along one fixed direction derived from the ecliptic, which is
face-on only for the one system whose elements are ecliptic. Every
exoplanet system — measured against the plane of the sky, perpendicular to
the line of sight to its own host star — was being presented nearly
edge-on, a smear of overlapping ellipses. The settle direction is now
taken relative to whichever plane the system was measured in, so all of
them read as discs. The solar system is unmoved, which a test pins.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WaySiNst4HhDXBHnMy8p5G
The map stopped at the catalogued 50 pc around the Sun — 0.33% of the
Galaxy's width — and looked like a point cloud with a search box.
Adds the galactic scale above it and the heads-up display the reference
map is built from.
The Galaxy is not a third coordinate space. It is the same parsec space
four orders of magnitude further out, so the model and the star field
crossfade against camera distance instead of switching, and the Sun stays
where it really is: 8.18 kpc out, on the Orion Spur, between the
Sagittarius and Perseus arms. The depth range scales with that distance —
one fixed near/far pair cannot both fly into a star and hold the Galaxy.
The structure in shared/astro/galaxy.ts is measured: the directions of the
centre and the north galactic pole, which fix the disc's 63 degree tilt
against the celestial equator; the Sun's galactocentric distance; and a
radius, azimuth and pitch angle per arm. The particles scattered around it
are not, and cannot be — dust hides the disc, so no catalogue holds the
Galaxy's stars. The view says so, and the model fades out before the
camera reaches the 50 pc where the real stars are.
The rest is the look: polar grids lying in the galactic plane with drop
lines from the Sun's neighbours, a scale ladder, a readout panel, range,
reticle and frame brackets. Two things had to give way for it. The
deep-sky shell is the sky as seen from here, so it dissolves rather than
letting the camera fly through a wall of nebulae, and so does the skybox,
which is a photograph taken from inside the thing now being viewed from
outside. Labels are picked by screen separation rather than distance
alone: the Sun's fifteen nearest neighbours are all inside four parsecs
and printed as one unreadable clump.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WaySiNst4HhDXBHnMy8p5G