Using NED to Search for Extragalactic Objects

(Latest Revision: 28 October 2009)

Find Redshift-Independent Distances by Object Name

This page allows you to search NED's list of redshift-independent distances by object name. NED's name interpreter recognizes most of the well-known prefixed names used in the literature (e.g. NGC 224, IRAS F00400+4059, 1ES 0039+409). NED Standard Names has more information on NED's naming conventions.

Data Entry

Type the name of the object you wish to search for in the "Object name:" box. The NED interface allows substantial freedom in formats and conventions for names, so type the name in any format you wish. When you submit your search, NED's name interpreter will attempt to translate your input into a name that NED recognizes.

If it cannot interpret the name you typed, a page will appear with a message explaining the most likely problem with your input. These usually fall into three categories. In all three cases, click your browser's "Back" button to go back to the search page, and enter another object name.

(1) If the name you entered has an acceptable catalog name, but the object number within the catalog is not within the range of numbers for that catalog, the page will tell you this. An example is "M111"; there are only 110 entries in the Messier catalog.

(2) If the catalog name itself is ambiguous, the page will list the acceptable possibilities. An example is "A123"; this could be "Abell 123", "Arakelian 123", "Arp 123", "Asiago1 023", or "[RC1] A1203".

(3) If the name interpreter does not recognize the catalog, the page will sometimes suggest alternative catalogs, sometimes not. In either case, click the "Back" button and try another name.


When a search has completed successfully, the interface opens a new page with the object's name and all redshift-independent distances that NED currently has available for the object. The help page available there has more information about the data returned by your search.

NED Standard Names

Object names are separated into catalog identifier and member identifier. The name interpreter checks the catalog identifier to certify that it points uniquely to a catalog recognized by the database. The name interpreter then checks the member identifier to certify that it corresponds to the conventions of the catalog identified (e.g. is it a sequential number, or a combination of numbers and letters, etc?), and that it does not exceed certain limits (e.g. the number of objects in catalog). The left hand column of the following table contains examples of input names recognized by the interpreter. The right hand column shows the NED standard formats.
n33 NGC 0033
U 12 UGC 00012
mk1000 MRK 1000
M 3-4-5 MCG +03-04-005
ZW23.1 CGCG 023-001
1zw23 I Zw 023
PKS0350+23 PKS 0350+23
4C23.7 4C +23.07

Names with square bracket prefixes (e.g. "[HB89]" and "[WB92]") usually come from papers published in journals, while those names with unbracketed prefixes (e.g. "NGC" and "IRAS") usually come from separately published catalogs. There are exceptions, however; examples include "[RC2]" and "87GB". Some names have combination prefixes (e.g. "87GB[BWE91]" and "ABELL 400:[D80]").

Objects in multiple systems without existing unique names are formed by the name of the system itself followed by "NEDnn", where "nn" is a decimal number starting with "01" (example: "ARP 294 NED01" and "ARP 294 NED02"). Similarly, objects found only in catalog notes are given names beginning with the name of the cataloged object followed by "NOTESnn" (example: "UGC 01562 NOTES01" and "UGC 01562 NOTES02"). Sources named in non-optical catalogs or lists, which are later found to be coincident with galaxies but which are not renamed, have "ID" appended to their original names (example: "IRAS 04356+3412 ID"). In this case, the Preferred Object Type is also changed to "Galaxy".

Note that recognition by the interface of the nomenclature used for the object name does not guarantee that the name exists in the Database. This recognition signals that at present parts of the catalog are in the Database, and that the intent is to eventually include at least the extragalactic portion of that catalog in NED.

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