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Full Frame Image (FFI) Display

This tool enables you to browse the Kepler field of view using the currently available FFI and FFI Uncertainty images, and to identify specific objects observed by GALEX, SDSS, and 2MASS in the Kepler field, as well as Kepler objects for which data are now public, "dropped," or published. The timestamp in the FFI file names are in the format yyyydddhhmmss, where ddd refers to Day of Year (for example, 114 = April 24 UTC), and times refer to the end of the exposure.

See the README.txt file in the FFI ftp directory for more information on the WCS corrections. Because the spacecraft rotates 90 degrees each quarter (clockwise in the image below), objects will appear in four different CCD channels. For example, in the image below representing the detector position in quarter 1, a target in channel 1 will appear sequentially in channels 53, 81, and 29, before returning to channel 1 in quarter 5.

For FFIs delivered before Oct. 2011, we recommend using SAOImage ds9 to correctly display the celestial coordinate system. Outdated WCS keywords exist in the FFI headers that cause some FITS viewers, eg. Gaia and Skycat, to display the wrong coordinates. The problem has been remedied in all FFIs delivered after Sep. 31, 2011. More recently, all the FFIs were reprocessed to include a one minute barycentric time correction. The corrected files were made available online at MAST in June, 2013.

Display channel:
for FFI image:
Kepler Field of View Image