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SAGE IRAC Epoch 1 and Epoch 2 Archive

Metadata Updated: September 19, 2025

The Spitzer Space Telescope Survey of the Large Magellanic Cloud Legacy Project Surveying the Agents of a Galaxy's Evolution (SAGE) traces the life cycle of observable matter that drives the evolution of a galaxy's appearance. SAGE has revealed over 6 million sources including ~150,000 evolved stars, ~50,000 young stellar objects and the diffuse interstellar medium with column densities > 1.2×1021 cm -2. The data will provide fundamental insights into the physical processes of the interstellar medium, the formation of new stars and the injection of mass by evolved stars and their relationships on the galaxy-wide scale of the Large Magellanic Cloud.In comparison to the catalog, the archive has more source fluxes (fewer nulled wavelengths) and some more sources but these additions have more uncertainty associated with them. For the catalog, the S/N must be greater than [6, 6, 6, 10] for IRAC bands [3.6um], [4.5um], [5.8um] and [8.0um] for the flux to appear in the corresponding wavelength column. Whereas for the archive, the S/N must be greater than [5, 5, 5, 5] for IRAC bands [3.6um], [4.5um], [5.8um] and [8.0um]. For the catalog, sources with neighbors within a 2" radius are excluded (culled). For the archive, sources within a 0.5" radius are excluded. The difference in criteria for the catalog and archive creation is more complex and described in Section 5.2 of the SAGE Data Delivery Document.This archive contains Epoch 1 only and Epoch 2 only sources.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025
Publisher NASA/IPAC Infrared Science Archive
Maintainer
Identifier ivo://irsa.ipac/spitzer/catalog/sage/sagei-ep1ep2ar
Data Last Modified 2025-09-10
Category Astrophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id d23b9835-3dae-4f36-9633-07738b6d2bd0
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://irsa.ipac.caltech.edu/data/SPITZER/SAGE/doc/SAGEIRACv3_descriptions.html
Program Code 026:000
Source Datajson Identifier True
Source Hash 2397a01082170a3aacb119b5fbeb76e6e787b3e8ac81c460094ca62b7a0b7a7e
Source Schema Version 1.1

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