Ready for JWST Time-Series Data? Here’s What You Need to Know

The Transiting Exoplanet Community Early Release Science Program is providing representative spectroscopic time-series data for four JWST observing modes, together with analysis cookbooks, open-source tools, and instrument performance benchmarks. We will observe 1) a transit of WASP-39b with NIRISS/SOSS, NIRCam/F322W2, and NIRSpec/G395H and PRISM modes, 2) an occultation of WASP-18b with NIRISS/SOSS, and 3) a full-orbit phase curve of WASP-18b with MIRI/LRS. The program is built around two open Data Challenges, the first occurring before science operations using simulated data and the second occurring shortly after data acquisition. The goals of the first Data Challenge are to 1) catalyze the development of open-source analysis tools that convert raw data to spectroscopic time series, planetary spectra, and atmospheric properties and 2) perform meaningful comparisons between different methodologies. In early 2022, the program delivered a full suite of simulated data to the community and hosted its first Data Challenge. We provide an overview of the transiting exoplanet community ERS program, a description of the simulated data products available to the community, and lessons learned during the Data Challenge. We briefly describe the open-source tools that are available and the challenges that drive continued development leading up to data acquisition and the second Data Challenge later in the year.