Total Lunar Eclipse in the Day Night Band

November 19th, 2021 |
NOAA-20 Day Night Band, 19 November 2021 (Click to enlarge)

NOAA-20 Day Night Band imagery from early morning (from the VIIRS Today website at CIMSS) on 19 November 2021 shows the impact of the total lunar eclipse on Day Night Band imagery. A lunar eclipse will always occur during a Full Moon; ample lunar illumination off the east coast accompanied that descending NOAA-20 pass between about 0635 and 0640 UTC (as shown in this orbital path image from this website) — just as the lunar eclipse was starting. By the time NOAA-20 overflew the central US (0815 to 0825 UTC), near totality was occurring. The overflight on the west coast (0955 to 1005 UTC) occurred as the eclipse was starting to wane, so a bit more lunar illumination was available.

A similar Day Night Band image from Suomi-NPP (also from the VIIRS Today website) is below, and it shows similar differences in swath illumination. The west coast overpass by Suomi-NPP occurred around 1050 UTC; by then the eclipse had ended. Suomi NPP Day Night Band imagery is also available at the NASA Worldview site.

Suomi-NPP Day Night Band imagery from early morning 19 November 2021 (Click to enlarge)

Total solar eclipse of 21 August 2017 – a satellite perspective

August 21st, 2017 |

* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing*

GOES-16 CONUS Sector images (at 5-minute intervals)

GOES-16

GOES-16 “Red” Visible (0.64 µm) images [click to play animation]

During the total solar eclipse of 21 August 2017,  the lunar umbra was evident on imagery from the GOES-16  0.5 km resolution (at satellite sub-point) “Red” Visible band (0.64 µm) (above) and 1.0 km resolution Near-Infrared “Vegetation” band (0.86 µm) (below).

GOES-16 Near-Infrared

GOES-16 Near-Infrared “Vegetation” (0.86 µm) images [click to play animation]

The shadow was also prominent in other Visible and Near-Infrared bands, as shown in a 4-panel comparison of GOES-16 “Blue” Visible (0.47 µm, upper left), “Red” Visible (0.64 µm, upper right), “Vegetation” (0.86 µm, lower left) and “Snow/Ice” (1.61 µm, lower right) images (below).

GOES-16

GOES-16 “Blue” Visible (0.47 µm, upper left), “Red” Visible (0.64 µm, upper right), “Vegetation” (0.86 µm, lower left) and “Snow/Ice” (1.61 µm, lower right) images [click to play animation]

GOES-16 true-color Red-Green-Blue (RGB) images from the SSEC Geostationary Satellite site (below) showed another view of the shadow. A GOES-16 Full-Disk true-color animation (courtesy of  Kaba Bah, CIMSS) is available here; a composite of eclipse shadow images can be seen here.

GOES-16 true-color RGB images [click to play animation]

GOES-16 true-color RGB images [click to play animation]

The 3.9 µm Shortwave Infrared band is also sensitive to reflected solar radiation — particularly that which is reflected from land surfaces and cloud tops composed of small spherical supercooled water droplets (and to a lesser extent, small ice crystals) — which causes this band to sense warmer (darker gray to black) brightness temperatures compared to the other ABI infrared bands. Therefore, a loss of sunlight within the eclipse shadow will lead to cooling (lighter shades of gray) 3.9 µm brightness temperatures (below).

GOES-16 Shortwave Infrared (3.9 µm) images [click to play animation]

GOES-16 Shortwave Infrared (3.9 µm) images [click to play MP4 animation]

Taking a closer look at eastern Missouri and southern Illinois as the solar eclipse shadow was passing over that region shortly after 1800 UTC (1:00 pm local time), GOES-16 “Red” Visible (0.64 µm) images (below) revealed that the pronounced decrease of incoming solar radiation appeared to temporarily suppressed the development of widespread boundary layer cumulus clouds. Note that increase in hourly surface temperatures was also halted, with some locations even experiencing a slight cooling (1-3 ºF) due to reduction of heating within the lunar umbra.

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with hourly surface reports plotted in yellow [click to play animation]

GOES-16 Shortwave Infrared (3.9 µm) images (below) also showed a slight cooling — seen as a lighter shade of red enhancement — across the region.

GOES-16 Shortwave Infrared (3.9 µm) images, with hourly surface reports plotted in yellow [click to play animation]

GOES-16 Shortwave Infrared (3.9 µm) images, with hourly surface reports plotted in yellow [click to play animation]

GOES-16 Mesoscale Sector images (at 1-minute intervals)

GOES-16 "Red" Visible (0.64 µm) images, with station identifiers plotted in yellow [click to play animation]

1-minute GOES-16 “Red” Visible (0.64 µm) images, with station identifiers plotted in yellow [click to play animation]

A “floating” Mesoscale Sector provided 1-minute imagery during the eclipse (above).

Polar-orbiting satellite images (Terra MODIS, and Suomi NPP VIIRS)

Terra MODIS Visible (0.65 µm). Land Surface Temperature product, Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Terra MODIS Visible (0.65 µm), Land Surface Temperature product, Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images [click to enlarge]

A toggle between Terra MODIS Visible (0.65 µm), Land Surface Temperature product, Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images (above) showed the eclipse shadow as it was centered over western Nebraska around 1748 UTC. Without a time series of MODIS Land Surface Temperature product images, it is difficult to gauge the exact amount of surface cooling brought about within the shadow of totality. A large-scale high resolution Terra MODIS Visible image is available here (courtesy of Liam Gumley, SSEC).

Suomi NPP VIIRS Visible (0.64 µm), Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm), Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

A comparison of Suomi NPP VIIRS Visible (0.64 µm), Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (above) showed the shadow center over eastern Tennessee around 1833 UTC. A closer comparison of Day/Night Band and Infrared images (below) revealed the  presence of cloud features that made it difficult to see a signature of any city lights that may have come on in the Nashville TN (KBNA) metropolitan area.

Suomi NPP VIIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Suomi NPP VIIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

“Blood Moon” total lunar eclipse, and a selenelion

October 8th, 2014 |

A “Blood Moon” total lunar eclipse occurred between 09:15 UTC and 12:34 UTC on 08 October 2014. One effect of this eclipse can be seen in a comparison of nighttime “during eclipse” and “after eclipse” Suomi NPP VIIRS 0.7 µm Day/Night Band images (above). The 11:33 UTC “during eclipse” Day/Night Band image appears somewhat dim and washed out, due to limited illumination by only red sunlight being refracted by the Earth’s atmosphere into the eclipse shadow. Less than 2 hours later, the 13:14 UTC Day/Night Band image appears much more bright with crisp cloud feature details, due to an abundance of illumination from the Full Moon.

A few hours after sunrise in North America, a portion of the Moon was captured on the GOES-13 (GOES-East) 0.63 µm visible channel image at 16:30 UTC (below). Note how the edges of the Moon appear slightly jagged, caused by the fact that it was moving (setting) behind the Earth as the GOES-13 imager instrument was scanning horizontally step-wise from north to south. In addition, at the point where the edge of the Moon meets the edge of the Earth, there is a “lensing effect” where the Earth’s atmosphere is refracting light from the Moon and creating the illusion of a curved wedge of dark space that is visible within the atmosphere.

Speaking of sunrise, an interesting aspect of this lunar eclipse was that it was a rare “selenelion”, when the rising sun in the east could be seen at the same time as the non-eclipsed portion of the setting moon in the west (Space.com article). This selenelion was captured at 12:03 UTC or 7:03 am local time by the east-looking and west-looking rooftop cameras on the Space Science and Engineering Center building (below; image captures courtesy of John Lalande, SSEC).

Total solar eclipse shadow crossing northeastern Australia and the South Pacific Ocean

November 13th, 2012 |

MTSAT-1R 0.7 µm visible channel images

MTSAT-1R 0.7 µm visible channel images

The shadow from a total solar eclipse could be seen moving east-southeastward across northeastern Australia and the adjacent waters of the South Pacific Ocean on Japanese MTSAT-1R 0.7 µm visible channel images (above).

The solar eclipse shadow was also evident on a visible image from the Korean COMS-1 satellite (below).

COMS-1 visible channel image

COMS-1 visible channel image

As the eclipse shadow continued to move eastward, it was seen on a US NOAA GOES-15 0.63 µm visible channel image (below).

GOES-15 0.63 µm visible channel image

GOES-15 0.63 µm visible channel image