ExoEcho: Exoplanet Ephemerides Change Observations. III. A JWST Survey for Transit Timing Variations of 37 Exoplanets
- 1Sun Yat-sen University
Abstract
Transit timing variations (TTVs) provide a powerful probe of planetary dynamics and orbital evolution. We extend the ExoEcho project by incorporating James Webb Space Telescope (JWST) transit observations and analyze 84 light curves of 37 exoplanets, including 20 hot Jupiters, 11 Neptune-like planets, and six super-Earths. We derive updated transit ephemerides and conduct a systematic search for long-term and periodic TTV signals. We identify two strong TTV candidates, including HATS-6 b and HAT-P-18 b. The hot Jupiter HATS-6 b exhibits a long-term trend with P ̇ = 230.5 ± 46.8 ms yr − 1 , potentially driven by tidal interactions with its host star. In addition, the Neptune-like planet HAT-P-18 b shows periodic TTV signal with amplitude of 92.9 ± 13.7 s. We also show that the previously claimed positive period derivative in WASP-121 b is inconsistent with our new transit timing data. Although continued monitoring is required to confirm these findings, our results demonstrate the potential of JWST for high-precision transit timing and extend TTV studies beyond the traditional hot-Jupiter population to lower-mass exoplanets.
Versions
Related
- Galactic archaeology meets exoplanets: linking stellar birth radii to exoplanet demographics
- How dust particles orbiting white dwarfs can reveal undetected co-orbiting exoplanets I. Exoplanet on a circular orbit
- Identifying deformed exoplanets with JWST and Ariel: A target selection metric for phase curve observations
- A Wavelet-Integrated Search Pipeline for Narrowband Technosignatures in FAST Observations of 33 Exoplanet Systems
- Testing the equivalence principle with lunar laser ranging residuals from different planetary and lunar ephemerides
BibTeX
@article{wu2026exoecho,
title = {{ExoEcho: Exoplanet Ephemerides Change Observations. III. A JWST Survey for Transit Timing Variations of 37 Exoplanets}},
author = {Yunke Wu and Zixin Zhang and Xinyue Ma and Wenqin Wang and Siqi Guo and Cong Yu and Shangfei Liu and Dichang Chen and Bo Ma},
journal = {The Astrophysical Journal Supplement Series},
year = {2026},
month = oct,
doi = {10.3847/1538-4365/aea075},
url = {https://iopscience.iop.org/article/10.3847/1538-4365/aea075},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - ExoEcho: Exoplanet Ephemerides Change Observations. III. A JWST Survey for Transit Timing Variations of 37 Exoplanets
AU - Yunke Wu
AU - Zixin Zhang
AU - Xinyue Ma
AU - Wenqin Wang
AU - Siqi Guo
AU - Cong Yu
AU - Shangfei Liu
AU - Dichang Chen
AU - Bo Ma
PY - 2026
DA - 2026/10/13
JO - The Astrophysical Journal Supplement Series
DO - 10.3847/1538-4365/aea075
UR - https://iopscience.iop.org/article/10.3847/1538-4365/aea075
AB - Transit timing variations (TTVs) provide a powerful probe of planetary dynamics and orbital evolution. We extend the ExoEcho project by incorporating James Webb Space Telescope (JWST) transit observations and analyze 84 light curves of 37 exoplanets, including 20 hot Jupiters, 11 Neptune-like planets, and six super-Earths. We derive updated transit ephemerides and conduct a systematic search for long-term and periodic TTV signals. We identify two strong TTV candidates, including HATS-6 b and HAT-P-18 b. The hot Jupiter HATS-6 b exhibits a long-term trend with P ̇ = 230.5 ± 46.8 ms yr − 1 , potentially driven by tidal interactions with its host star. In addition, the Neptune-like planet HAT-P-18 b shows periodic TTV signal with amplitude of 92.9 ± 13.7 s. We also show that the previously claimed positive period derivative in WASP-121 b is inconsistent with our new transit timing data. Although continued monitoring is required to confirm these findings, our results demonstrate the potential of JWST for high-precision transit timing and extend TTV studies beyond the traditional hot-Jupiter population to lower-mass exoplanets.
SN - 0067-0049
SN - 1538-4365
ER -