How Small of a Rocket Signature can GOES “see”?
There are many examples of NOAA‘s GOES ABI detecting the spectral signatures of large rockets. These include GOES-S, GOES-T, GOES-U, GOES-U boosters, Starliner, Falcon 9, Ariane, Himawari-9, Antares, etc. If the rocket is large enough, there is often a signal in each of the 16 ABI bands. Of course the timing of the ABI scan needs to correspond to the times of the rocket’s brightest / hottest phases, which is more likely if there’s a meso-scale sector covering the area of interest, either at 1-min or 30-second cadence.
Smaller rockets, such as the Firefly, may be be an order of magnitude darker/cooler compared to a Falcon, given their very different maximum thrust. The Firefly maximum rocket thrust is approximately 165,000 lbf (pound-force) [736.1 kN] and the Falcon 9 is about 1,700,000 lbf [7,000 kN].
Firefly on July 4th
Late on July 3rd (local time, early July 4th UTC) there was a Firefly rocket launch from Vandenberg Air Force base.
Given the smaller rocket size, a fair question is if it can be seen by the GOES ABI. Often the “Meso 1” sector from GOES-West covers most of California (the default location for this sector). This was the case on July 3, into July 4, 2024. A first look at the 16 spectral bands on the ABI, using default enhancements, shows no discernible rocket plume signature. (The signal of the explosion on the maiden Firefly rocket flight was seen by each band of the ABI.)
Yet, a highly-enhanced (stretched) ABI band 5 (1.61 micrometers) showed a glimpse of the rocket launch. (Some instrument noise is also seen.)
The rocket signature is more evident in the nighttime micro-physics RGB combination. Watch near the coast for the first signature.
While it’s hard to tell, there may be some indication of the plume in the 11-12 micrometer split window difference from the CONUS sectors.
H/T
The GOES ABI data was accessed via the UW/SSEC Data Services. McIDAS-X, geo2grid and AWIPS software were used to generate the images. More UW/CIMSS Satellite Blogs associated with rocket signatures. T. Schmit works for NOAA/NESDIS/STAR and is stationed in Madison, WI.