The JWST Resolved Stellar Populations Early Release Science Program IV: The Star Formation History of the Local Group Galaxy WLM

Understand

We present the first star formation history (SFH) and age-metallicity relation (AMR) derived from resolved stellar populations imaged with the JWST NIRCam instrument.

• The target is the Local Group star-forming galaxy WLM at 970 kpc.
• The depth of the color-magnitude diagram (CMD) reaches below the oldest main sequence turn-off with a SNR=10 at M_F090W=+4.6 mag; this is the deepest CMD for any galaxy that is not a satellite of the Milky Way.
• We use Hubble Space Telescope (HST) optical imaging that overlaps with the NIRCam observations to directly evaluate the SFHs derived based on data from the two great observatories.