Isolated star stellar motions#

Position, proper motion, and parallax for isolated stars, fit using associated source measurements, with positions for associated reference objects if available.

Schema: IsolatedStarStellarMotions table

Access#

This table is accessible via the TAP and Butler services.

Recommended access service: TAP

TAP#

Citation: NSF-DOE Vera C. Rubin Observatory (2026); Legacy Survey of Space and Time Data Preview 2: IsolatedStarStellarMotions searchable catalog https://doi.org/10.71929/rubin/3382553 [BibTeX]
Table name: IsolatedStarStellarMotions
Columns: 28
Rows: 318,429,415

Butler#

Citation: NSF-DOE Vera C. Rubin Observatory (2026); Legacy Survey of Space and Time Data Preview 2: isolated_star_stellar_motions dataset type https://doi.org/10.71929/rubin/3382552 [BibTeX]
Dataset type: (‘isolated_star_stellar_motions’, {instrument, skymap, tract}, ArrowAstropy)
Format: Parquet
Number of Butler datasets: 7,809

Description#

An “isolated” star is defined as an unblended, point-like detection with a signal-to-noise ratio between 8 and 1000 that, after being spatially matched within a matching radius of 1 arcsec across all visits and bands in a given tract, has no other candidate within 2 arcsec of its average position.

The Isolated Star Stellar Motions catalog provides a best-fit position (ra, dec), proper motion in mas/yr (raPM, decPM), and parallax in mas at a reference epoch for all identified isolated stars. The raPM parameter already includes the cos(decl.) factor. The reference epoch in Modified Julian Date (MJD) is included in the catalog. Each entry includes a unique identifier and, where applicable, the ID, position, proper motion, and parallax of the matched reference Gaia DR3 source. The catalog also includes 1-sigma uncertainties for all astrometric parameters, along with the off-diagonal elements of the covariance matrix.

Processing#

The position, proper motion, and parallax are computed jointly across the matched visits using FitStellarMotionTask. For details, see Astrometric calibration.

Tutorials#

See the 200-level catalog Tutorials for a notebook on the isolated stars stellar motions table.