The TSIS-1 solar observations overlapped with SORCE measurements for two years during solar cycle minimum conditions. Shown here are the SORCE TIM and TSIS-1 TIM total solar irradiance measurements (SORCE TIM native TSI scale in black and then adjusted by 0.88 W/m² to match TSIS-1 TIM TSI scale at the TSI determined solar minimum time denoted by the dotted line). TSIS-1 measurements are now capturing the rise of SC25.