Band-integrated "white" phase curve of WASP-43b using 61 orbits from the Hubble Space Telescope. The systematics-corrected flux values are binned in time, normalized to the stellar flux, and have 1σ error bars. Each color represents data acquired from a different HST visit. The phase curve depicts steadily increasing and decreasing observed flux which originates from different longitudes of the tidally-locked planet as it makes one complete rotation. Light from the planet is blocked near an orbital phase of 0.5 as it is eclipsed by its host star. The shape of the phase curve is noticeably asymmetric. Inset, for comparison, is the white light curve primary transit.
Phase-resolved emission spectrum of WASP-43b relative to the stellar flux. We illustrate the planet's emitted light in 15 spectrophotometric channels (colored points with 1σ error bars) and compare our measurements to best-fit atmospheric models (colored lines). White diamonds depict the models binned to the resolution of the data. The absorption feature from 1.35 to 1.6 μm confirms the presence of water vapor in WASP-43b's atmosphere. For clarity, we only display planet-to-star flux ratios at four planet phases: full (0.5, secondary eclipse), wanning gibbous (0.62), half (0.75), and wanning crescent (0.88). A time-lapse video of the WASP-43b's phase-resolved emission spectrum is available here.