VLA FIRST: Faint Images of the Radio Sky at Twenty-cm

A December 2014 catalog from the Very Large Array (VLA) FIRST survey, covering 10,000 square degrees of the North and South Galactic Caps. The project, produced by the National Radio Astronomy Observatory (NRAO), maps the radio sky with 5" resolution, a typical noise level of 0.15 mJy, and contains approximately 90 sources per square degree at the 1 mJy detection threshold. The catalog is hosted and served via the MAST archive.

Use Cases

• Cross-match radio sources with optical counterparts based on the 30% counterpart rate with the Sloan Digital Sky Survey mentioned in the description
• Analyze the spatial distribution and density of faint radio sources based on the ~90 sources per square degree statistic
• Study resolved radio source structures based on the description that ~35% of sources have structure on scales from 2-30"
• Perform cone searches for radio objects in specific regions of the sky using the described MAST service endpoint

Strengths

• Covers a large area of 10,000 square degrees of the sky
• Provides high-resolution imagery with 5" resolution and 1.8" pixels
• Has a quantified source density of ~90 sources per square degree at the 1 mJy threshold
• Includes cross-matching potential with ~30% of sources having optical counterparts

Limitations

• Column-level documentation is absent; field semantics must be inferred after download
• Row count is unknown, which may limit suitability assessment
• The catalog was published in 2014; newer surveys may offer more recent data

Provenance

Source

National Radio Astronomy Observatory (NRAO) Very Large Array, hosted by the Mikulski Archive for Space Telescopes (MAST)

Collection Method

Produced using the NRAO Very Large Array and an automated mapping pipeline

Time Range

Survey data culminating in a catalog published December 17, 2014

Freshness

Last updated 2026-03-13 18:41:12.779790; freshness should be verified

Geography

North and South Galactic Caps