GOODS

GOODS
Name	GOODS
Country	United States
Organization	Space Telescope Science Institute, European Southern Observatory, National Aeronautics and Space Administration
Established	2002

GOODS

Great Observatories Origins Deep Survey is an astronomical multiwavelength survey combining observations from space- and ground-based facilities to study galaxy formation and evolution across cosmic time. Designed to exploit the capabilities of the Hubble Space Telescope, Chandra X-ray Observatory, Spitzer Space Telescope and large ground observatories, the survey targeted two well-studied fields to create deep imaging and spectroscopic datasets. GOODS enabled cross-comparisons among datasets from the Hubble Deep Field, Sloan Digital Sky Survey, Two Micron All Sky Survey, and later wide-field surveys, becoming a cornerstone for high-redshift galaxy studies, active galactic nuclei demographics, and cosmic star-formation history.

Overview

GOODS combined deep imaging and spectroscopy in two fields: the GOODS-North field centered on the Hubble Deep Field North and the GOODS-South field overlapping the Chandra Deep Field South and the Great Observatories Origins Deep Survey South. The program integrated observations from Hubble Space Telescope instruments such as Advanced Camera for Surveys and Wide Field Camera 3 with data from Chandra X-ray Observatory, Spitzer Space Telescope, and ground-based facilities including the Keck Observatory, Very Large Telescope, Subaru Telescope, Gemini Observatory, and the Atacama Large Millimeter/submillimeter Array. GOODS aimed to measure galaxy morphologies, photometric redshifts, stellar masses, and obscured star formation from ultraviolet to radio wavelengths, linking results to theoretical frameworks from groups like the Millennium Simulation teams and cosmological constraints from the Wilkinson Microwave Anisotropy Probe and Planck (spacecraft).

History and development

GOODS was proposed in the early 2000s as a natural successor to deep-field projects such as the Hubble Deep Field, Hubble Ultra Deep Field, and the Chandra Deep Field. Principal investigators and teams from the Space Telescope Science Institute and international partners coordinated observing plans to leverage scheduled missions like Spitzer and long-term programs on VLT and Keck Observatory. The initial phase integrated archival datasets from programs including the Sloan Digital Sky Survey and targeted new deep observations to complement ongoing surveys such as the Great Observatories Origins Deep Survey contemporaries and precursor programs run by the European Southern Observatory and National Radio Astronomy Observatory.

Over successive observing cycles, GOODS evolved through coordinated campaigns: deep optical/NIR imaging via Hubble Space Telescope proposals, deep X-ray mapping with Chandra X-ray Observatory programs, mid-infrared imaging from Spitzer Space Telescope Legacy Surveys, and spectroscopic follow-up by teams using Keck Observatory DEIMOS and LRIS instruments, VLT FORS2 and VIMOS, and Gemini Observatory multi-object spectrographs. The field selections intentionally overlapped legacy fields like Hubble Deep Field North and Chandra Deep Field South to maximize legacy value and synergy with programs such as the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey.

Survey design and observations

GOODS targeted two 10'×16' fields chosen for low Galactic extinction, visibility to northern and southern observatories, and existing ancillary data from programs such as Hubble Deep Field, Chandra Deep Field South, and Great Observatories Origins Deep Survey South. The observing strategy combined ultra-deep imaging in multiple bands: optical bands from Hubble Advanced Camera for Surveys and near-infrared bands from Hubble Wide Field Camera 3; X-ray exposures from Chandra X-ray Observatory reaching megasecond depths; mid-infrared imaging from Spitzer Space Telescope IRAC and MIPS channels; and submillimeter/radio mapping from facilities like Atacama Large Millimeter/submillimeter Array and the Very Large Array.

Spectroscopic campaigns targeted candidate high-redshift galaxies, active galactic nuclei, and emission-line objects using instruments on Keck Observatory, Very Large Telescope, Subaru Telescope, and Gemini Observatory, providing secure redshifts for calibration of photometric redshift techniques developed alongside surveys such as the COSMOS survey and the DEEP2 Redshift Survey.

Data reduction and products

Data reduction combined pipeline processing from mission teams (e.g., Space Telescope Science Institute pipelines for Hubble Space Telescope data, Chandra X-ray Center pipelines for Chandra), community-developed software, and catalog assembly efforts coordinated by GOODS science teams. Public products included high-level image mosaics, multiwavelength source catalogs, photometric redshift catalogs calibrated with spectroscopic redshifts from Keck and VLT campaigns, X-ray source lists, and infrared source catalogs from Spitzer. Ancillary data releases incorporated radio catalogs from the Very Large Array and submillimeter catalogs from arrays like ALMA.

Value-added products encompassed stellar-mass estimates using spectral energy distribution fitting with templates from libraries used in programs tied to the Sloan Digital Sky Survey and photometric toolkits developed by collaborations including the CANDELS team. GOODS data were distributed through archives maintained by the Space Telescope Science Institute and participating observatory archives.

Scientific results and impact

GOODS produced influential results on galaxy assembly, cosmic star-formation history, and black hole growth. Studies using GOODS data quantified the evolution of the cosmic star-formation rate density at z~1–6, investigated the morphology–mass relation in cohorts of galaxies, and identified candidates for passive galaxies at high redshift. GOODS X-ray catalogs advanced demographics of obscured and unobscured active galactic nuclei, informing models previously constrained by surveys such as the Chandra Deep Field South and complementing wide-field constraints from the Sloan Digital Sky Survey.

The survey enabled discoveries of Lyman-break galaxies and Lyman-alpha emitters studied in the context of reionization constraints drawn alongside results from the Wilkinson Microwave Anisotropy Probe and theoretical predictions from the Illustris and EAGLE simulations. GOODS results informed follow-up programs with James Webb Space Telescope and shaped target selection for spectroscopic surveys on Keck and VLT.

Collaborations and related surveys

GOODS was inherently collaborative, involving teams from Space Telescope Science Institute, European Southern Observatory, National Aeronautics and Space Administration, National Science Foundation-funded groups, and international observatories including Keck Observatory, Very Large Telescope, Subaru Telescope, Gemini Observatory, Atacama Large Millimeter/submillimeter Array, and Very Large Array. Related surveys and successor projects include CANDELS, COSMOS, DEEP2 Redshift Survey, Hubble Ultra Deep Field, Hubble Deep Field, Chandra Deep Field South, and UltraVISTA, forming a network of deep and wide extragalactic surveys that together underpin current models of galaxy evolution and cosmology.

Category:Astronomical surveys