COSMOS2020 Classic: Photometry and Redshift Catalog for 1.7 Million Sources

1.7 million sources in the 2 square degree COSMOS field are cataloged with multi-wavelength photometry. Approximately 966,000 sources have measurements from all available broad-band data using both aperture and profile-fitting photometry. Photometric redshifts are computed for all sources using two independent codes, LePhare and EAZY, with sub-percent precision for bright sources.

Use Cases

• Train photometric redshift estimation models based on the multi-wavelength photometry.
• Compare galaxy properties based on the two independent photometric redshift codes, LePhare and EAZY.
• Benchmark source detection algorithms using the catalog of 1.7 million identified sources.
• Analyze photometric measurement techniques using the traditional aperture and profile-fitting (The Farmer) data.

Strengths

• Covers 1.7 million sources, providing a large sample for statistical analysis.
• Approximately 966,000 sources have measurements from all available broad-band data.
• Photometric redshifts are computed with two independent codes for validation.
• Achieves sub-percent photometric redshift precision for sources brighter than i < 21 magnitude.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Source detection and photometry performed on the COSMOS field; photometric redshifts computed using LePhare and EAZY.

Time Range

null

Freshness

Last updated 2026-03-13 19:07:45.442618; freshness should be verified.

Geography

Covers the 2 square degree COSMOS field.