Types of SearchesDetailed data for many objects in NED may be retrieved via that object's name. Not all objects in NED have detailed data. Click on any of the following Search or Help links.
Image Searches by Object NameDescriptionThis option allows you to search the database for published images, for cutouts of galaxies in the Extended Source Catalog from the Two Micron All-Sky Survey, the Digitized Sky Survey, or for maps (usually radio frequency isophote maps) for a given object. While most of the images NED currently stores on-line are optical, infrared, and radio images of galaxies, we are also collecting isophote maps and other graphical representations of extragalactic data. InputType an object's name in the "Object Name:" window. Click the "Submit Query" button to initiate the search. Click the "Reset" button to clear the object name window. ResultsWhen a search has completed successfully, the interface opens a new page with a summary listing of the available images and maps for the object. Each listing is accompanied by a small "postage stamp" representation. Click on that to have your browser open a new window showing the image at full resolution (this assumes that your browser supports viewing of GIF files, either internally, or via a helper application). FITS formatted versions of the images may be downloaded by clicking on "Retrieve" in the "FITS File" column of the table. You may also view the "FITS Header", and use Aladin to manipulate the image and overlay catalogs on it. Other information given includes the waveband (in astronomical jargon) used for the image, the image dimensions in arcminutes, the image resolution in arcseconds, the telescope used to obtain the image, and the reference to a published description of the image. You may also change the image size for DSS images. Images from the Digitized Sky Survey appear courtesy of AURA/STScI.
Back to the Image Search
Input Page.
Spectra SearchesDescriptionThis option allows you to search NED's archive of spectra, and to examine and retrieve the spectra. You may also work with them with Specview, a tool developed by Ivo Busko at STScI. InputType an object's name in the "Object Name:" window. Choosing an "Extended Name Search" gives you three options: "Only if input name has multiple components" will return spectra only for those galaxies with multiple components in NED, any of which have spectra in NED's spectral database. "Never" displays spectra only for the top-level component, while "Always" will search for all names beginning with your galaxy's name. Two results pages are possible. The default is to display a compact page with links to the detailed data and descriptions, but you may also choose to have the full description page display immediately. Choose the number of spectra you wish to display on a single output page. "Slit and spectrum previews" will display the position of the observing slit or aperture on a DSS cutout, and will also show a postage-stamp preview of the spectrum itself. Finally, you may also constrain your request to a specific paper (highlight the title, author, and refcode you wish to see), a specific bandpass, or spectral line. After you've made your selections, click the "Submit Query" button to initiate the search. The "Reset" button returns the input screen to its default state.
Go to the Spectra Search
Input Page.
Photometry and SED Data SearchesDescriptionThis option allows you to search the database for photometric data for a given object. All the information that you will need to correctly interpret the data is also carried along with the photometry. In addition to the retrieved photometric data for an object, NED provides a spectral energy distribution plot of those data with several display options. InputType an object's name in the "Enter Object Name:" window. Then select an "Output Table Format." The default gives a summary list of photometry as published and transformed to standard units (mJy), but the summary list is also available with the photometry only as published or only transformed to standard units. The summary list is preceded on the output page by a spectral energy distribution (SED) plot in standard units (log [flux density] in Janskys vs. log [frequency] in Hz), though you may change these by clicking on any of the "SED Plot Options" buttons. You may also turn the plot's error bars on or off; they are on by default. The default SED plots over a fixed range of frequency (or wavelength) for easy comparison among different objects. If a data point falls outside of that range, a message to that effect is displayed on the plot. You may then replot the data using autoscaling to show all the data points. Finally, choose the format of the tabular data you want. Currently, the options include
After you've made your selections, click the "Photometry" button to initiate the search. The "Reset" button returns the input screen to its default state.
Go to the Photometry Data Search
Input Page.
Position Data SearchesDescriptionThis option allows you to search the database for position data from various lists and catalogs for a given object. This provides an easy way to compare positions from different wavelength regimes for the same object. InputType an object's name in the "Enter Object Name:" window. Then choose a coordinate system for your output display: the default is "Equatorial", but you may also display the output in "Ecliptic", "Galactic", or "Supergalactic" coordinates. Finally, if you chose "Equatorial" or "Ecliptic" coordinate output, you may also choose an equinox between 1500.0 and 2500.0, with either Besselian (e.g. B1950.0) or Julian (e.g. J2000.0) dates. The default is J2000.0. Also, choose the format of the tabular output data you want. Currently, the options include
After you've made your selections, click the "Positions" button to initiate the search. The "Reset" button returns the input screen to its default state.
Go to the Position Data Search
Input Page.
Diameter SearchesDescriptionThis option allows you to search the database for published diameters, axis ratios, or position angles for a given object. NED has optical and radio diameters from SDSS, RC3, ESO-B, ESO-LV, UGC, MCG, and many others. InputType an object's name in the "Enter Object Name:" window. Also, choose the format of the tabular output data you want. Currently, the options include
Go to the Diameter Data Search
Input Page.
Redshift Data SearchesDescriptionThis option allows you to search the database for published redshifts or radial velocities for a given object. NED has optical and HI redshifts from SDSS, RC3, HMS, LCRS, LBQS, and many other catalogs, papers, and lists. InputType an object's name in the "Enter Object Name:" window. By default, NED does not display redshifts as velocities if the velocity calculated by V = cz is greater than 30,000 km/sec. If you wish to change this limit, enter the new limit in the "Velocity displayed as:" window. Also, choose the format of the tabular output data you want. Currently, the options include
Click the "Redshifts" button to initiate the search. Use the "Reset" button to return the redshift search screen to its default values.
Go to the Redshift Data Search
Input Page.
Redshift-Independent Distance Data SearchesDescriptionNED maintains a list of published redshift-independent distances for extragalactic objects. This option allows you to search that list by object name. InputType an object's name in the "Object Name:" window. Click the "Search" button to initiate the search. Use the "Reset" button to clear the input object name window.
Go to the Redshift-Independent Distance Data Search
Input Page.
Classifications and Attributes by Object NameDescriptionThis option allows you to search the database for classifications, types, and other attributes -- such as optical or radio morphology, or AGN spectral classification -- from various lists and catalogs for a given object. NED has most of the classifications from RC3, RSA, UGC, and the 12th edition (2006) of Véron-Cetty and Véron's AGN/QSO/BL Lac list, and many others. InputType an object's name in the "Object Name:" window. Click the "Search" button to initiate the search. Use the "Reset" button to clear the input object name window.
Go to the Classifications by Object Name Data
Search Input Page.
Notes on ObjectsDescriptionNotes from several astronomical catalogs and thousands of papers are also included in NED. Among those catalogs currently represented areInputType an object's name in the "Enter Object Name:" window. Also, choose the format of the tabular output data you want. Currently, the options include
Click the "Notes" button to initiate the search. Click the "Reset" button to clear the object name window.
Go to the Notes Search
Input Page.
NED Name Prefix SearchType an object's name prefix in the "Enter name prefix (acronym):" window. Click the "Look Up Name Prefix" button to initiate the search. Click the "Reset" button to clear the window. Many of the names used in NED have adopted the format "[AAAYY]" or "[AAA20YY]" where "AAA" are the first initials of the authors' family names, and "YY" is the year of publication of their paper. The square brackets "[" and "]" are mandatory and must be entered for the search to be successful. Square brackets are also used for some catalogs (e.g. "[RC1]", "[RC2]", and "[RC3]"), but not others (e.g. "UGC", "1WGA", and "IRAS"). Some prefixes include spaces (e.g. "IRAS F" and "FAUST NGP"). If you cannot find the prefix you want using the prefix search, you may click on View all object name prefixes currently in NED where the name prefixes are listed alphabetically with the "square-bracket names" at the end of the list.
Go to the Name Prefix Search
Input Page.
Data EntryNED's name interpreter recognizes most of the well-known prefixed names used in the literature (e.g. M31, NGC 224, IRAS F00400+4059, 1ES 0039+409). NED Standard Names has more information on NED's naming conventions. 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.
NED Standard NamesObject 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.
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".
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