Sub-Saturns planets orbiting stars that are hotter than about 6,100 K can have orbits that are highly tilted.
sub-Saturn is a planet whose size (radius) is between that of Neptune and Saturn.
Scientists used both transit data from TESS and radial-velocity / spectroscopic data (including the so-called Rossiter–McLaughlin effect) to measure how tilted the orbit is.
Rossiter–McLaughlin effect: When a planet transits its star, it blocks part of the rotating stellar surface. Because one side of the star is moving toward us and the other side is moving away, the observed stellar spectrum is slightly distorted, causing an apparent shift in the star’s radial velocity.
Measured obliquities in hot-star sub-Saturn systems are not exactly 90°, but cluster around ~65°, which accords with a theoretical idea called secular resonance crossing.
Secular resonance crossing mechanism means that —
Over a long period of time, the gravitational pull from the star (and possibly other planets) slowly changes the direction of the planet’s orbit. It is slow, long-term gravitational process where the planet’s orbit gets strongly tilted (to near-polar) because its orbital motion and the star’s spin motion temporarily match.
𝜓 final: final obliquity. By the above equation we can know that sub saturn planet obliquity depends on different parameters.
Source: https://arxiv.org/html/2510.20740v1
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