Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Skip to content

Hewitt&Burbidge(1991)CatalogofExtragalacticEmission-LineObjects

Metadata Updated: September 19, 2025

This is the Hewitt & Burbidge (1991) Optical Catalog of Extragalactic Emission-Line Objects Similar to Quasi-Stellar Objects. It contains a total of 935 galaxies which have optical properties similar to QSOs. Most of the objects appear to be nonstellar. The majority, more than 700, have redshifts z that are <= 0.2, and most have been classified as Seyfert galaxies, N systems, or radio galaxies. The redshift distribution peaks at z ~ 0.025, but there are about 200 powerful radio galaxies in the extended tail of the distribution which have z > 0.2. There is a separate and distinct peak in the redshift distribution at z = 0.06. Notice that this catalog does not include star-like objects with emission-line redshifts >= 0.1 (these can be found in the HEASARC QSO database which contains the Revised and Updated Catalog of Quasi-Stellar Objects" of Hewitt, A. and Burbidge, G. 1993, ApJS, Vol. 87, pp. 451-947). Neither does it contain LINERs (sometimes called Seyfert 3 galaxies) or starburst galaxies. This database was created by the HEASARC in February 2001 based on CDS/ADC Catalog VII/178 (table1.dat). This is a service provided by NASA HEASARC .

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 High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/exgalemobj
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 697595cb-df65-4aeb-9ea4-d1ed501bb26e
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/exgalemobj.html
Program Code 026:000
Source Datajson Identifier True
Source Hash c287add3c2b1d40c8c7d35124f5350bc698f6198876c854f0790451fcc0022b5
Source Schema Version 1.1

Didn't find what you're looking for? Suggest a dataset here.