2 Commits
Author SHA1 Message Date
SenrokaiandClaude Opus 5 4eb61ff58e Draw each HYG star at Gaia's distance, and keep the ones Hipparcos misplaced
HYG and Gaia were both cut at 250 pc, each on its own distance. A star
Hipparcos put at 200 pc and Gaia at 300 was kept by the first, never
downloaded from the second, and drawn at 200. That is where 83% of the
9 691 mid-magnitude HYG stars without a Gaia counterpart came from, and at
the median Hipparcos had them a third too close. The mirror case, Hipparcos
outside and Gaia inside, dropped the HYG row and left its Gaia entry
anonymous.

Gaia's own Hipparcos cross-match (hipparcos2_best_neighbour, a fixed DR3
table of 99 525 rows) gives a usable Gaia distance for 97 751 of them.
placementDistancePc keeps a star either survey puts inside the cutoff, and
draws every kept star at the better measurement, inside the cutoff or not.
57 121 HYG stars now sit at Gaia's distance. 6 833 of them are past 250 pc:
Zet Per 230 -> 259 pc, 35 Ori 137 -> 330, 44 Cnc 223 -> 613, and the
farthest, HIP 69445, at 8.7 kpc. 3 666 stars that Hipparcos put outside are
now kept, and 3 656 of them give a Gaia entry its name.

The cross-match is required rather than skipped when unreachable. Without
it, every one of those stars would move back to its Hipparcos distance, and
the published map would flip with the archive's availability. The ESA TAP
answered it with a 500 at first and in 102 s on the next try. So fetches
now retry 5xx and network failures twice, after 30 s and 120 s, in the
fetch every source goes through. The refresh job also carries the Gaia DR3
responses from run to run in the Actions cache: the release is frozen, and
a live re-fetch has already reproduced stars.bin byte for byte.

423 651 stars (+10), 61 168 HYG rows folded into Gaia entries (+3 656),
351 597 unnamed designations (-3 656). 10 886 HYG survivors and 23 unmerged
pairs under an arcsecond, both inside the merge gate's ceilings. The same
1 972 exoplanets have a host; KELT-4 A b and MWC 758 c now sit on their
named star.

The HUD's "Radius" becomes "Survey radius": 250 pc is where Gaia is
surveyed to, and no longer the edge of the map.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016jxMkwA2rbicdGxHosecYi
2026-09-11 19:07:12 +02:00
Claude efa9e4084a Draw the whole catalogue, and build the aggregation the rest would need
Two things, one verified and one that cannot be.

The render budget is now the whole catalogue: 68388 stars, one instanced
draw call, which is what a GPU should be asked to do. The budget itself
stays, because the catalogue is meant to grow past what any machine should
draw at once — Gaia alone could contribute a million — and at that point
the selection is what keeps the field legible rather than a grey wash. A
`?stars=` override handles the machines that cannot, including the
software rasterizer the end-to-end suite runs against, whose frame rate is
two orders of magnitude below a real GPU's and which was measuring the
rasterizer rather than the app.

The aggregation is the second thing, and none of it has run. Every ESA,
NOIRLab, SDSS and Euclid endpoint is unreachable from here — only GitHub
raw is, which is why HYG and OpenNGC are the current sources. So this is
infrastructure and a Gaia query written against the published DR3 schema,
not data.

What the framework encodes is that these surveys are not interchangeable.
The distinction is not size but whether a catalogue knows how far away its
objects are, because a 3D map cannot place a star it only has a direction
for. Gaia is the only one of the five that can add stars here, because it
is the only one that measures parallaxes. DECaPS2 has fifty times Gaia's
object count and photometry alone — not one of its 3.32 billion objects
can be placed in depth. Euclid's bulge is 8 kpc away, where a parallax is
microarcseconds; its contribution would be imagery. SDSS-V and SAGA are
keyed to stars something else already places, so they enrich rather than
extend. Those roles are recorded as data the ETL prints, not as prose that
can drift.

Overlapping catalogues are reconciled on direction rather than on 3D
proximity, which is the one non-obvious part. Two surveys agree on a
star's direction to within an arcsecond and disagree on its distance by
tens of per cent, so a star at 200 pc is 50 pc from itself between
catalogues while being unmistakably the same object. Matching in 3D would
need a tolerance so loose it swallowed real neighbours. The better
parallax wins where both reach; where only one does, the star stays.

Names become dense-with-holes with a source dictionary, because a survey
catalogue has no proper names — writing "Gaia DR3 4472832130942575872"
once per star would cost 25 MB per million to repeat what two adjacent
fields already say. An empty entry costs three bytes and is regenerated on
load. The Sun needed its own case in the merge: it sits at the origin, has
no direction to compare, and appears in every catalogue.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WaySiNst4HhDXBHnMy8p5G
2026-08-05 08:51:54 +00:00