Prospects of detecting rotational flatness of exoplanets from space-based photometry
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866908457922199552 |
|---|---|
| author | Kálmán, Sz. Csizmadia, Sz. Bernabó, L. M. Szabó, R. Szabó, Gy. M. |
| author_facet | Kálmán, Sz. Csizmadia, Sz. Bernabó, L. M. Szabó, R. Szabó, Gy. M. |
| contents | In the era of photometry with space-based telescopes, such as CHEOPS (CHaracterizing ExOPlanets Satellite), JWST (James Webb Space Telescope), PLATO (PLAnetary Transits and Oscillations of stars), and ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey), the road has opened for detecting subtle distortions in exoplanet transit light curves -- resulting from their non-spherical shape. We investigate the prospects of retrieval of rotational flatness (oblateness) of exoplanets at various noise levels. We present a novel method for calculating the transit light curves based on the Gauss-Legendre quadrature. We compare it in the non-rotating limit to the available analytical models. We conduct injection-and-retrieval tests to assess the precision and accuracy of the retrievable oblateness values. We find that the light curve calculation technique is about $25$\% faster than a well-known analytical counterpart, while still being precise enough. We show that a $3 σ$ oblateness detection is possible for a planet orbiting bright enough stars, by exploiting a precise estimate on the stellar density obtained e.g. from asteroseismology. We also show that for noise levels $\geq 256$ ppm (expressed as point-to-point scatter with a $60$~s exposure time) detection of planetary oblateness is not reliable. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2507_15359 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Prospects of detecting rotational flatness of exoplanets from space-based photometry Kálmán, Sz. Csizmadia, Sz. Bernabó, L. M. Szabó, R. Szabó, Gy. M. Earth and Planetary Astrophysics In the era of photometry with space-based telescopes, such as CHEOPS (CHaracterizing ExOPlanets Satellite), JWST (James Webb Space Telescope), PLATO (PLAnetary Transits and Oscillations of stars), and ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey), the road has opened for detecting subtle distortions in exoplanet transit light curves -- resulting from their non-spherical shape. We investigate the prospects of retrieval of rotational flatness (oblateness) of exoplanets at various noise levels. We present a novel method for calculating the transit light curves based on the Gauss-Legendre quadrature. We compare it in the non-rotating limit to the available analytical models. We conduct injection-and-retrieval tests to assess the precision and accuracy of the retrievable oblateness values. We find that the light curve calculation technique is about $25$\% faster than a well-known analytical counterpart, while still being precise enough. We show that a $3 σ$ oblateness detection is possible for a planet orbiting bright enough stars, by exploiting a precise estimate on the stellar density obtained e.g. from asteroseismology. We also show that for noise levels $\geq 256$ ppm (expressed as point-to-point scatter with a $60$~s exposure time) detection of planetary oblateness is not reliable. |
| title | Prospects of detecting rotational flatness of exoplanets from space-based photometry |
| topic | Earth and Planetary Astrophysics |
| url | https://arxiv.org/abs/2507.15359 |