Spitzer Legacy Project

Spitzer Legacy Project
Name	Spitzer Legacy Project
Mission type	Astronomical survey
Operator	NASA
Spacecraft	Spitzer Space Telescope
Launch	2003-08-25
Instruments	IRAC, MIPS, IRS
Status	Completed

Spitzer Legacy Project The Spitzer Legacy Project was a coordinated series of astronomical surveys conducted with the Spitzer Space Telescope to produce uniform infrared datasets for the astronomical community. It provided deep, wide-area imaging and spectroscopy that served researchers working on galaxy evolution, star formation, exoplanets, planetary science, and cosmology across institutions such as NASA, Jet Propulsion Laboratory, Caltech, Harvard–Smithsonian Center for Astrophysics, and international partners including European Space Agency teams.

Overview

The project comprised several flagship programs executed during the cryogenic and warm phases of the Spitzer Space Telescope mission, including coordinated efforts like the Great Observatories Origins Deep Survey, the SINGS program, and the FEPS legacy survey, and interfaced with missions such as Hubble Space Telescope, Chandra X-ray Observatory, XMM-Newton, Herschel Space Observatory, and GALEX. It targeted diverse astronomical populations across well-studied fields like the GOODS-North, GOODS-South, COSMOS, Lockman Hole, and Extended Groth Strip, enabling cross-comparison with catalogs from Sloan Digital Sky Survey and redshift programs conducted at facilities including the W. M. Keck Observatory, the Very Large Telescope, and the Subaru Telescope.

Objectives and Scientific Goals

Primary goals included measuring the infrared spectral energy distributions of galaxies to constrain models of galaxy formation and evolution, assessing disk evolution around young stars to inform theories by researchers at institutions such as University of California, Berkeley and Massachusetts Institute of Technology, and producing legacy-quality datasets to support follow-up by facilities like ALMA, JWST, and future observatories. The surveys aimed to quantify star-formation rates, dust properties, and stellar mass assembly in samples tied to surveys like 2MASS, DEEP2 Redshift Survey, and the VVDS while facilitating studies of debris disks related to programs at European Southern Observatory and analyses by teams associated with the Max Planck Institute for Astronomy.

Survey Design and Instruments

Observations used Spitzer instruments including the Infrared Array Camera (IRAC), Multiband Imaging Photometer for Spitzer (MIPS), and the Infrared Spectrograph (IRS). Survey strategies balanced depth and area with programs ranging from ultra-deep fields in GOODS to wide-area mapping in SWIRE and targeted spectroscopy in programs like GO and GTO allocations. Field selection considered legacy datasets from the Hubble Deep Field, multiwavelength coverage from Chandra Deep Field South, and ancillary data from ground-based observatories such as Palomar Observatory, Kitt Peak National Observatory, and the Canada–France–Hawaii Telescope.

Major Datasets and Catalogs

Major deliverables included IRAC and MIPS imaging mosaics, IRS spectral cubes, photometric catalogs, and value-added products such as photometric redshift catalogs cross-matched with DEEP2, zCOSMOS, PRIMUS, and spectroscopic compilations from Keck/DEIMOS and VLT/VIMOS. Prominent catalogs produced by the legacy effort were incorporated into archival services at the NASA/IPAC Infrared Science Archive and linked with multiwavelength databases like the NED and the Vizier service at Centre de Données astronomiques de Strasbourg.

Key Discoveries and Impact

Legacy surveys yielded high-impact results: constraints on obscured star-formation histories in the universe, characterization of luminous infrared galaxies and ultraluminous infrared galaxies tied to merger-driven models, discovery and census of protoplanetary and debris disks informing planet-formation timescales, and infrared detection of high-redshift galaxies contributing to reionization-era studies. These results were cited in publications from teams at Princeton University, University of Cambridge, ETH Zurich, and Johns Hopkins University, and influenced follow-up programs with Herschel, ALMA, and the James Webb Space Telescope.

Data Processing and Archive Access

Data reduction pipelines leveraged community software and institutional pipelines developed at NASA/IPAC, Spitzer Science Center, Caltech, and partner institutions, producing calibrated basic calibrated data (BCD), post-BCD mosaics, and higher-level catalogs. Processed datasets and documentation were archived at repositories including the NASA/IPAC Infrared Science Archive and mirrored to archives used by the European Space Agency and national data centers in archives at STScI and the Canadian Astronomy Data Centre for access by users from universities and observatories worldwide.

Collaborations and Funding

The project was led by teams funded through NASA programs with contributions and collaborations involving the Jet Propulsion Laboratory, Caltech, academic groups at University of Arizona, University of Oxford, Max Planck Society, and international partners from institutions such as CNRS, CSIC, and INAF. Funding and resource support came from NASA mission allocations, institutional grants, and international agency partnerships that enabled coordinated proposal calls, data release schedules, and community workshops at venues like AAS meetings and dedicated conferences at COSPAR and university symposia.

Category:Astronomical surveys Category:Spitzer Space Telescope