Fig 7: Spot filling factors of HAT-P-11 as a function of time. Filling factors derived from rotational variability in Kepler and TESS light curves (using Equation 2 of Rackham et al. 2019) are compared with values inferred from multi-component spectral fits to HST G102 and G141 data. Independent chromospheric activity measurements (S-index values from the literature) are shown on the right axis. The Kepler era exhibits relatively high filling factors with substantial variability, whereas the TESS epochs indicate a transition to markedly lower spot coverage. Red vertical dotted lines mark the epochs of JWST observations
Sweet deep dive from Prajwal Niraula, @benrackham.bsky.social et al. on a star near and dear to my heart. #stellarastro 🔭
Evidence from HST, Kepler, TESS, and ground-based spectroscopy all agree: 2024 #JWST observations HAT-P-11 were taken near activity minimum.
arxiv.org/abs/2603.24585
![False-color image made with MUSE on the VLT: right in the middle of a square frame edged in white, you see the bright white dwarf as it travels through space. Around it spreads this striking bow shock nebula in vivid colors — the outermost curve shines a deep red from hydrogen emission (Hα), while closer in you get those greens from singly-ionized nitrogen ([N II]) and blues coming from doubly-ionized oxygen ([O III]). A few extra bright patches dot the area nearby. The whole central scene is placed over a wider background filled with soft reddish stars, which gives the picture a nice dramatic feel.](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:5odp2okktic3ychbdqiw3kxi/bafkreibotj5zff3fz3jwsof2xffjx7megzunfvupbycdf5vqkjs74x425i)
