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With more than 1000 hours of observation from Feb 2016 to Oct 2019, theSpitzer Exploration Program Red Worlds (ID: 13067, 13175 and 14223) exclusivelytargeted TRAPPIST-1, a nearby (12pc) ultracool dwarf star orbited by seventransiting Earth-sized planets, all well-suited for a detailed atmosphericcharacterization with the upcoming JWST. In this paper, we present the globalresults of the project. We analyzed 88 new transits and combined them with 100previously analyzed transits, for a total of 188 transits observed at 3.6 or4.5 $\mu$m. We also analyzed 29 occultations (secondary eclipses) of planet band eight occultations of planet c observed at 4.5 $\mu$m to constrain thebrightness temperatures of their daysides. We identify several orphantransit-like structures in our Spitzer photometry, but all of them are of lowsignificance. We do not confirm any new transiting planets. We estimate forTRAPPIST-1 transit depth measurements mean noise floors of $\sim$35 and 25 ppmin channels 1 and 2 of Spitzer/IRAC, respectively. most of this noise floor isof instrumental origins and due to the large inter-pixel inhomogeneity of IRACInSb arrays, and that the much better interpixel homogeneity of JWSTinstruments should result in noise floors as low as 10ppm, which is low enoughto enable the atmospheric characterization of the planets by transittransmission spectroscopy. We construct updated broadband transmission spectrafor all seven planets which show consistent transit depths between the twoSpitzer channels. We identify and model five distinct high energy flares in thewhole dataset, and discuss our results in the context of habitability. Finally,we fail to detect occultation signals of planets b and c at 4.5 $\mu$m, and canonly set 3$\sigma$ upper limits on their dayside brightness temperatures (611Kfor b 586K for c).

TRAPPIST-1: Global Results of the Spitzer Exploration Science Program {\it Red Worlds}