HCG: 463 Galaxies in 100 Hickson Compact Groups with Astrometry and Photometry

The HCGGALAXY table contains data on 463 galaxies within 100 compact groups identified from the Palomar Observatory Sky Survey. NASA HEASARC created the table in 1999, based on machine-readable tables from the ADC/CDS data centers, and updated it in 2005. It provides astrometry, photometry, morphological types, and radial velocities for the galaxies, drawing from three key astronomical publications.

Use Cases

• Classify galaxy morphological types based on the visual and isophotal analysis data provided for 210 galaxies.
• Analyze group dynamics and membership using radial velocities, given for 457 galaxies with 84% within 1000 km/s of the group median.
• Study photometric properties of galaxies in compact environments using the derived CCD photometry.
• Investigate the isolation and surface brightness criteria that define Hickson Compact Groups.

Strengths

• Contains data for 463 galaxies across 100 systematically identified compact groups.
• Radial velocities are provided for 457 galaxies (98.7% of the sample).
• Morphological information is available for 210 galaxies, derived from isophotal analysis or visual inspection.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• The dataset does not contain properties of the groups as units; that data is in a separate related table.

Provenance

Source

NASA HEASARC, based on machine-readable tables from the ADC/CDS data centers (CDS catalog VII/213).

Collection Method

Data derived from CCD images and systematic search of the Palomar Observatory Sky Survey red prints.

Time Range

Based on publications from 1989, 1992, and 1994.

Freshness

Last updated 2026-03-13 20:15:07.663215; freshness should be verified.

Geography

Celestial coverage from the Palomar Observatory Sky Survey.