Timothy D. Rehm, Caitlyn Altermatt, Lee Bernard, Andrea Bocchieri, Nathaniel Butler, Oliver Carey, Ryan C. Challener, John Hartley, Kyle R. Helson, Daniel P. Kelly, Kanchita Klangboonkrong, Andrei L. Korotkov, Maura Lally, Edward Leong, Nikole K. Lewis, Steven Li, Michael Line, Stephen F. Maher, Ryan McClelland, Lorenzo V. Mugnai, Peter C. Nagler, C. Barth Netterfield, Vivien Parmentier, Enzo Pascale, Jennifer Patience, L. Javier Romualdez, Paul A. Scowen, Gregory S. Tucker, Ingo Waldmann

The EXoplanet Climate Infrared TElescope (EXCITE) is a balloon-borne mission dedicated to measuring spectroscopic phase curves of hot Jupiter-type exoplanets. Phase curve measurements can be used to characterize an exoplanet's longitude-dependent atmospheric composition and energy circulation patterns. EXCITE carries a 0.5 m primary mirror and moderate resolution diffraction-limited spectrograph with spectral coverage from 0.8--3.5 um. EXCITE is designed to fly from a long-duration balloon (LDB). EXCITE will observe through the peak of a target's spectral energy distribution (SED) and through spectral signatures of hydrogen and carbon-containing molecules. In this paper, we present the science goals of EXCITE, detail the as-built instrument, and discuss its performance during a 2024 engineering flight from Fort Sumner, New Mexico.