How to use the Hipparcos/Tycho WWW Interface


How to query the catalogues

  • Specifying your query constraints.
  • Specifying the search box for coordinate.
  • Submitting Your Query
  • Setting up output modes

  • Tabular output
  • How to limit the number of retrieved records?
  • Want more info on each retrieved records?
  • You want to use a full screen mode output?
  • What about the target name?

  • Using the target source field
  • What about those other links?

  • Anchor to other archives and services.

  • How to query the catalogues


    Specifying Query Constraints.

    When you first enter a WDB query form you will see a lot of query fields like this :

    Parallax

    The checkbox you see to the left of the field name determines whether or not the value of this item appears in the tabular output. In the above example the name of the detector will appear in the tabular output.

    These are the operands that are available for querying in the fields.
    <
    Less than.
    >
    Greater than.
    <=
    Less than or equal to.
    >=
    Greater than or equal to.
    !=
    Not equal to.
    =
    Equal to. Can be used with wild cards.
    ~
    As = but ignoring case.
    ==
    Exact match (No wild-cards)
    *
    Wild-card in strings ( A*B will match AB, AxB, AxxxxB, etc. ).
    ..
    A range of values (ex.: 234.56 .. 678.9 ).
    |
    OR
    Will match any of the specified expressions (ex.: =123 OR > 5000 OR < 1 ).

    If, for example, you wish to search for all stars with parallaxes greater than 300 milliarcseconds then you would do the following: Parallax
    You could restrict it even further by asking for parallaxes between 300 and 400 milliarseconds. Parallax


    Specifying the search box for coordinates

    In most catalogues, it is not feasible to search directly by target names since there is no standard for naming astronomical targets. We strongly suggest that users use the SIMBAD resolver instead. Then any known astronomical names can be used with SIMBAD or NED providing the coordinates.

    To specify the search box around these coordinates, a box size (DD MM SS) is specified. The default box size is 10 arc minutes.


    Submitting Your Query

    To get the result of your query you have to submit it. At the top and at the bottom of the query form you will see a set of buttons like this :

    In order to to submit your request press the "Search" button. If you want to reset all the fields back to the way they where before you started entering qualifiers in them, press the "reset" button. (You could try to edit the "Dateobs" field above and then press the "Reset" button).


    Setting up output modes


    Tabular Output

    It is worth remembering that the checkboxes that appeared to the left of the query items on the query form are what determine which columns appear in the tabular output. If, for example, you have made a query and you can't find the telescope name on the output table, then go back to the query form and press the telescope checkbox and resubmit the query.

    How to limit the number of retrieved records?

    Right now, there is a default limit of 1000 in number of records one can retrieve from the database. If you are reaching this limit in your query result, it is more than likely that there are other observations that match your query criteria. You can either modify this limit or respecify your query. For internal reasons there is a hardcoded limit setup to 1500 records.

    Want more info on each retrieved records?

    For each records retrieved from the archive, there is a more link written as M. This allows the user to retrieve all known information concerning this particular entry.

    You want to use a full screen mode output?.

    There is a selection box on each form wich allows the user to be able to retrieve the information from each archive in full screen mode instead of the default tabular format. This is quite useful when only few records are expected since this mode could generates a tremendous amount of information.

    What about the target name


    Using the target source field

    For a catalogue search, we are providing 2 different sources for the target name. The default one is using SIMBAD or NED to resolve the name into coordinates. The search is then done using the precise standard coordinates from SIMBAD or NED and using the given search box, instead of the Hipparcos/Tycho star number.

    The second mode is using the Hipparocs/Tycho star number. This only works if you just happen to know exactly which object you're looking for.


    What about those other links


    Links to other archives and services.

    Each successful retrieval includes a number of links to other catalogues and archives. These are provided in concert with the Canadian Astronomy Data Center (CADC). These include the following:

    Link name Short description Example
    IRAS Link to the IRAS HCON images server at CADC http://cadcwww.dao.nrc.ca/cadcbin/universal/1212+12/0010/iras
    SIMBAD Query Simbad around the coordinate of this retrieved observation http://cadcwww.dao.nrc.ca/cadcbin/universal/1212+12/0010/simbad
    HST archive Query the HST archive around the coordinate of this retrieved observation http://cadcwww.dao.nrc.ca/cadcbin/universal/1212+12/0010/hst
    CFHT archive Query the CFHT archive around the coordinate of this retrieved observation http://cadcwww.dao.nrc.ca/cadcbin/universal/1212+12/0010/cfht
    ESO archive Query the ESO archive (NTT) around the coordinate of this retrieved observation http://cadcwww.dao.nrc.ca/cadcbin/universal/1212+12/0010/eso
    NED access Query NED around the coordinate of this retrieved observation http://cadcwww.dao.nrc.ca/cadcbin/universal/1212+12/0010/ned
    Digitized Sky Survey access
    DSS
    Query the Digitized Sky Survey access survey around the coordinate of this retrieved observation. http://cadcwww.dao.nrc.ca/cadcbin/universal/1212+12/0010/dss



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