slow-VGRF

Stars that have almost stopped moving — in the frame of the Galaxy.

The instantaneous Galactic rest-frame speed VGRF = |vgalactocentric| of a typical disc star is a few hundred km s⁻¹. This site is the interactive companion to A Probabilistic Gaia DR3 Catalogue of Stars with Very Low Galactic Rest-Frame Speeds (Humble 2026): a probability-scored sample of stars with P(VGRF< 25 km s⁻¹) — stars caught near an orbital turning point with almost no angular momentum. In any centrally concentrated potential they must fall back toward the inner Galaxy: their orbits are nearly radial plunges. Here you can browse every candidate, follow each step of the math, and integrate the orbits yourself — in the paper's own galactic potential models, live in your browser.

541
Tier A+B stars
P(V_GRF < 25 km/s) > 0.84 — the primary catalogue
1952
Tier A+B+C with orbits
P > 0.50, integrated 4 Gyr in each model
0.964
median eccentricity
point-estimate, adopted static model
116 pc
median pericentre
864 stars reach R < 100 pc (static); 1635 with the bar

3D orbit viewer →

Pick any of the 1952Tier A+B+C stars, choose a galactic potential model (static Hunter+2024, McMillan 2017, or the barred models across the paper's Ωp grid) and watch its 4-Gyr orbit integrate live — with the Sun and well-measured context stars for scale, and overlays that show the model itself at work.

Catalogue browser →

Filter and search all 20,829 candidate sources by tier, membership probability, quality flags and chemistry; every star has a full detail page with Monte Carlo orbit posteriors and both-model orbit summaries.

The math, step by step →

From five Gaia numbers to a catalogue probability: parallax zero-point, Bailer-Jones distance, the exact Galactocentric transform (all four solar-frame variants), VGRF, and the Monte Carlo tiering — with live numbers for real stars.

Ensemble figures →

Interactive versions of the paper's key figures: pericentre vs apocentre, E–Lz, the Toomre diagram, the sky map, and the smooth-continuation excess.

Provenance & caveats →

Release v1.0.8-review, DOIs, licensing — and the honest fine print: which numbers are model outputs, where actions are unreliable, and how the in-browser engine is validated against the published catalogue.