What is in databases
    Click here for data description
    SPIDR Installation Guide
    SPIDR User's Guide
    SPIDR Web-services Guide
How to work with data
    New SPIDR user
    Advanced SPIDR user
How to use the pages
    Select data set
    Data query
    Time series plot
    User data basket
    Time interval & sampling
    DMSP orbits search
    DMSP orbits viewer

SPIDR DMSP satellite image request


    This page is used to search for DMSP images in SPIDR

    Usage basics

    To search the DMSP orbital database, select the location, time of day, and satellite(s) desired. Placing the cursor on the map defines this "location", which can be viewed either during the ascending (night) or descending (day) protion of the orbit.

    The user can select the animated preview ("View images") or "View the detailed inventory" from the options at the bottom of the page. Inventory tables are created for all orbits.

    The search is performed with the user-defined date interval, which has to be set in advance using the SPIDR Time Ineterval ans Sampling page. Once set, the date interval will be the same for all datasets in SPIDR. It can be change or unset at any moment during the user session using the same Time Ineterval ans Sampling page.

    Search of images for a given location

    Users can specify a search location in two ways: positioning the cursor on the map, or entering latitude and longitude in the appropriate text boxes.

    To move the location cursor, the arrow button above the map should be selected. It can then be dragged around the map or paced by a single click.

    The map suppots basic GIS functions such as zoom and data overlay (political boundaries, cities, stable nighttime lights). To use zoom, the magnifying glass icon above the map must be selected and a box dragged over the desired area. Map layers are selectable by checkboxes in the map's legend.

    If the location coordinates are entered in the corresponding text fields of the request form, then this values will be used regardless search cursor location on the map.

    Other search options

    User can restrict search for orbits for a subset of DMSP satellites, using muliple satellite selection list on the page. By default, both daytime and nighttime orbital segments are present in the search results. The user can restrict search for only nighttime (ascending) or daytime (descending) DMSP orbits.