Plotting NED Objects on Finding Charts

(Latest Revision: 8 May 2009)

You may use this window to generate finding charts on your screen. If you have just done an object search, the window opens with the results of that object search in a data list. If you opened the window from NED's home page, the data list is empty so that you may enter your own object names and coordinates.

The window that displays the plot will also give you the opportunity to save the plot as a PostScript file which you may print or display locally. It also has an option to display or save an ASCII text file containing the data used to make the plot.

Input Parameters

If you do not want to plot your objects at the scale of the Palomar and SERC/ESO photographic sky surveys, click the "No" radio button and enter a scale in the input box. A convenient scale in "arcsec/mm" for viewing plots on your screen is the search radius in arcminutes that you used for your object search.

The default plot size at the scale of the sky surveys is 135 arcmin square. This corresponds to about 12 cm square for the plot area on a printed paper copy. The apparent size of the plot on your screen depends on your monitor size and resolution, and the size of your browser window.

SAO stars in the field of your object are plotted by default. If you do not want them plotted, click the "No" radio button.

You may use equatorial, ecliptic, Galactic, or supergalactic coordinates for your plot (the default is equatorial). Click the menu box to choose the coordinate system. Also choose an input equinox if you do not want the default value. Note that the equinox of the plot is always B1950.0 regardless of the input value.

Finally, you may choose to not plot any object in the search result list -- click the radio button at the end of that object's line -- or you may change the displayed coordinates and error ellipses.

Click the "Plot" button to generate the plot. When it is ready, a new window will open to display it.

Clicking the "Reset" button clears the plot options, but not the data list.


The objects are plotted at the listed positions using open ellipses of the size shown in the "MajUnc" and "MinUnc" columns, and orientation shown in the "PA" column. While these values are nominally the semimajor and semiminor axes, and the position angle, of the uncertainty ellipses associated with an object's position, you may replace these with any numbers you wish, e.g. diameters. If the values in "MajUnc" or "MinUnc" are smaller than 2 arcsec, the object is plotted as an "x" rather than as an ellipse. You may also change the positions themselves, if you have different positions you wish to enter.

Use your browser's "Back" button to return to your previous Sky Plot data page.

Back to the Sky Plot Input Data Page.

Return to NED's Home Page.