The Final ACT

The Atacama Cosmology Telescope (ACT) began observations of the microwave sky in 2008 and
continued until it was decommissioned in late 2022. I will present the new final sky maps from the experiment, which
are dominated by data taken in its last four seasons. After briefly discussing the steps in making maps
from raw time stream data and extracting angular power spectra, I will discuss our updated constraints on
the standard LCDM cosmological model and limits on various speculative extensions of this model. I will also give
a brief progress report on Simons Observatory, which will extend and broaden ACT’s scientific legacy
over the coming years.