CIMSS Satellite Blog

GOES-16 Visible (0.64 µm, left), Near-Infrared (1.61 µm, center) and Shortwave Infrared (3.9 µm, right) images [click to enlarge]

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

Visible and thermal signatures of the Space-X EchoStar 23 rocket launch were seen with GOES-16 imagery on 16 March 2017. The set of 3 images above consists of 5-minute CONUS sector scans at 05:54:33 UTC (about 5 minutes before launch), 05:59:33 UTC (around launch time) and 06:04:33 UTC (about 5 minutes after launch). The 05:59:33 UTC image was actually scanning the NASA Kennedy Space Center (station identifier KXMR)  area at 06:00:38 UTC, just after the 06:00 UTC launch time. A faint bright glow of the rocket booster was seen on the 0.5-km resolution Visible (0.64 µm) image; the 1-km resolution Near-Infrared (1.61 µm) rocket signature was much brighter, because this spectral band senses radiation from both visible and infrared portions of the electromagnetic radiation spectrum (which of the two was a stronger contributor to the bright signal is difficult to determine); the 2-km resolution Shortwave Infrared (3.9 µm) image displayed a warm (dark black enhancement) “hot spot”, although it was not exceptionally warm (with a 306.8 K maximum brightness temperature).

A “warm signal” was also observed on the three GOES-16 ABI Water Vapor bands: Lower-Level (7.3 µm), Mid-Level (6.9 µm) and Upper-Level (6.2 µm), as shown below.While water vapor is certainly a byproduct of rocket booster combustion, it is important to remember that the Water Vapor bands are first and foremost Infrared bands that sense the brightness temperature of a layer of moisture (which can vary in both altitude and depth, depending on the temperature/moisture profile of the atmosphere and/or the satellite viewing angle). In this case, the atmosphere was relatively dry over the region, with little moisture aloft to attenuate the rocket signature — shifting the roughly-corresponding GOES-13 Sounder*  water vapor weighting functions (from this site) to lower altitudes. However, moisture considerations aside, the rocket signature seen on the 05:59:33 UTC water vapor imagery was primarily a thermal anomaly.

GOES-16 Lower-Level Water Vapor (7.3 µm, left), Mid-Level Water Vapor (6.9 µm, middle) and Upper-Level Water Vapor (6.2 µm, right) images [click to enlarge]

* had the GOES-13 Sounder instrument been operational

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