A Discovery Tool for Astronomical Research
Hidden Defaults & Implicit Assumptions
StarGateVR makes many decisions on the user’s behalf — cross-match radii, quality cuts, row limits, coordinate conventions. Most of these are reasonable defaults, but researchers should know they exist. This page catalogs every implicit assumption we’ve identified, so the science is transparent and reproducible.
Last audit: February 2026
Parallax Quality Cuts
These filters are applied to every AI-generated Gaia ADQL query. The user does not see or request them.
• All queries: parallax > 0 — all negative-parallax stars excluded
• Near objects: parallax/parallax_error > 3 — low-significance measurements dropped
• Typical queries: parallax/parallax_error > 5 — stricter cut for most searches
• Distant objects (>3000 pc): parallax/parallax_error > 2 — relaxed for distant targets
• Most queries: pmra IS NOT NULL AND pmdec IS NOT NULL — stars without proper motion excluded
• Near searches (<20 pc): radial velocity requirement relaxed
Stars with poor astrometric solutions are silently excluded. This is scientifically reasonable but means incomplete samples for faint or distant populations.
MocaDB Membership Probability
banyan_prob >= 0.7 OR banyan_prob IS NULL
Members with BANYAN probability below 70% are silently discarded across all MocaDB query paths.
Row Limits and Result Ordering
• Gaia ADQL queries: SELECT TOP 2000 — maximum 2000 rows returned
• Multi-database spatial queries: TOP 500 or less
• AI analysis: 100 stars maximum sent to the language model
• eROSITA batch: 10 stars per batch, 50 max queries
• Multi-database enrichment: 100 coordinates max per run
• Gaia source_id queries: batched in groups of 100
Note: All Gaia queries default to ORDER BY phot_g_mean_mag. When the TOP cap is reached, the faintest stars are dropped first. This produces a brightness-biased sample.
Cross-Match Radii
All archives default to 5.0 arcsec cross-match radius:
• eROSITA: 5.0 arcsec
• SIMBAD: 5.0 arcsec
• 2MASS: 5.0 arcsec
• GALEX: 5.0 arcsec
• AllWISE: 5.0 arcsec
• Coordinate merge tolerance: 5.0 arcsec
Genuine matches beyond these radii are lost during enrichment. Source_id matching is preferred over positional matching when available (2MASS, AllWISE via Gaia cross-match tables).
eROSITA Match Quality Labels
• < 2 arcsec: “excellent”
• < 5 arcsec: “good”
• < 10 arcsec: “acceptable”
Adaptive Default Search Radius
When a user names an object without specifying a search radius:
• Object distance < 20 pc → 5 pc default radius
• 20–100 pc → 20 pc
• 100–500 pc → 50 pc
• > 500 pc → 100 pc
Consent and Sampling Thresholds
• ≤ 10 stars: auto-proceed, no consent
• 11–100 stars: asks for consent
• > 100 stars: always samples down to 100
• > 1000 stars: hard limit
If estimated enrichment time exceeds 120 seconds (~2 seconds per star), the system recommends sampling instead of full enrichment.