VIIRS M-band Pixel Aggregation and Bowtie Deletion

sample VIIRS scene
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Move your pointer across the above VIIRS scene to see how it is divided into individual scan lines. If you hover over any of the little red squares, you should see a zoomed-in version in this space. (JavaScript must be enabled.) The seven insets have been placed over: the scene edges (A and G), the nadir region (D), and the trasition regions (B, C, E, and F) between the different pixel aggregation zones labeled above.

Pixels omitted from each scan (bow-tie deletion) are outlined in red in the zoomed-in extracts. The pixels on either side of the nominal nadir position (Inset D) are outlined in yellow. The irregular shapes of the pixels in Inset F result from the intersection of non-nadir fields of view (the scan angle is approximately 45 degrees in this region) with the mountainous topography of the Appalachians.

Note that pixels get wider as one moves away from nadir except when transitioning to a different aggregation zone at which point the pixels abruptly get narrower again — as one would expect when going first from three samples per detector to two (Insets C and E) and then from two to one (Insets B and F).

There is very little overlap from one scan line to the next near the nadir portion of the scan. As one moves away from the nadir position, adjacent scan lines begin to overlap more and more even after the bow-tie deletion pixels are removed.

(If the scan line does not move with your pointer on the above image, make sure you are allowing JavaScript for this site and then try reloading this page in your browser.)

Inset G Inset F Inset E Inset D Inset C Inset B Inset A
32nd scan Inset G, scan 32 Inset F, scan 32 Inset E, scan 32 Inset D, scan 32 Inset C, scan 32 Inset B, scan 32 Inset A, scan 32
31st scan Inset G, scan 31 Inset F, scan 31 Inset E, scan 31 Inset D, scan 31 Inset C, scan 31 Inset B, scan 31 Inset A, scan 31
30th scan Inset G, scan 30 Inset F, scan 30 Inset E, scan 30 Inset D, scan 30 Inset C, scan 30 Inset B, scan 30 Inset A, scan 30
29th scan Inset G, scan 29 Inset F, scan 29 Inset E, scan 29 Inset D, scan 29 Inset C, scan 29 Inset B, scan 29 Inset A, scan 29
28th scan Inset G, scan 28 Inset F, scan 28 Inset E, scan 28 Inset D, scan 28 Inset C, scan 28 Inset B, scan 28 Inset A, scan 28
27th scan Inset G, scan 27 Inset F, scan 27 Inset E, scan 27 Inset D, scan 27 Inset C, scan 27 Inset B, scan 27 Inset A, scan 27
26th scan Inset G, scan 26 Inset F, scan 26 Inset E, scan 26 Inset D, scan 26 Inset C, scan 26 Inset B, scan 26 Inset A, scan 26
25th scan Inset G, scan 25 Inset F, scan 25 Inset E, scan 25 Inset D, scan 25 Inset C, scan 25 Inset B, scan 25 Inset A, scan 25
24th scan Inset G, scan 24 Inset F, scan 24 Inset E, scan 24 Inset D, scan 24 Inset C, scan 24 Inset B, scan 24 Inset A, scan 24