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Making your own galaxy selections from the RC3 catalogue

(Recommend for advanced users only.)

(The procedures described below use Visual Basic macros and for these to work you will need to make sure that the Excel macro security level is not set too high. Click here to see how to do this.)

Download the complete RC3 list in zipped format

Right click the link below and save the file (3 Mb) to your hard disc and then unzip it.

Zipped file of data for the whole RC3 galaxy catalogue

Make your selection

  1. Open the spreadsheet called rc3.xls containing all data for all 23,000 galaxies.

  2. In the blue and orange cells labelled Selection criteria (E4 to L5 at the top) enter the criteria you want to use to make your selection.

    There is space for eight different criteria. Only galaxies from the RC3 catalogue for which all eight criteria are true will then be extracted.

    Click here to find out what information is given about each galaxy that you could include in the criteria.

    IMPORTANT NOTE You must not leave any of the eight criteria blank or unspecified otherwise all 23,000 galaxies will get selected! If you do not need as many as eight criteria, just complete the unused criterion spaces with no in the top cell and >0 in the bottom cell . (This will mean that only galaxies numbered greater than zero in the catalogue will be selected. Since this applies to every single galaxy this means that this criterion will have no effect, apart preventing you getting all 23,000 galaxies in your list.)

    HINT: if you want to select for all disc galaxies, i.e. both spirals and lenticulars, use the criterion viewing >=0. Since only these two types of galaxy have a viewing angle listed, they will be the only ones selected.

  3. Click the Extract button, and when prompted, choose to save the list of selected galaxies to a suitable location on your hard disc, using a name that will help you to remember what it is.
  4. (Don't delete the spreadsheet rc3_blank.xls from the folder containing rc3.xls, otherwise this will not work.)

  5. An additional interactive version of each list is also saved. This will have the same filename but with _vis added at the end.

    You can use the interactive version to find out which galaxies will be visible from both Hawaii and Australia at a specific date and time. To do this, enter the required date and time, press F9, and wait while the spreadsheet recalculates (this might take a few minutes as the spreadsheet could be very big).

    The azimuth (bearing) and altitude of each object in the sky at both telescopes is also tabulated. and the object is marked as being observable if the altitude is 30 degrees or more. (Nearer to the horizon than this the atmosphere degrades the image.)

  6. Having entered the date and time on an interactive list, you can click the button labelled Make lists for this date and time and it will make observing lists for (1) Hawaii and (2) Australia. These lists are sorted so that the galaxies visible at the chosen date and time appear at the top.

 

Richard Beare, Institute of Education, University of Warwick            2nd February , 2006