A possible misaligned orbit for the young planet AU Mic c
Copyright policy )A possible misaligned orbit for the young planet AU Mic c
ABSTRACT The AU Microscopii planetary system is only 24 Myr old, and its geometry may provide clues about the early dynamical history of planetary systems. Here, we present the first measurement of the Rossiter–McLaughlin effect for the warm sub-Neptune AU Mic c, using two transits observed simultaneously with the European Southern Observatory's (ESO's) Very Large Telescope (VLT)/Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO), CHaracterising ExOPlanet Satellite (CHEOPS), and Next-Generation Transit Survey (NGTS). After correcting for flares and for the magnetic activity of the host star, and accounting for transit-timing variations, we find the sky-projected spin–orbit angle of planet c to be in the range $\lambda _{\mathrm{c}}=67.8_{-49.0}^{+31.7}$ degrees (1$\sigma$). We examine the possibility that planet c is misaligned with respect to the orbit of the inner planet b ($\lambda _{\mathrm{b}}=-2.96_{-10.30}^{+10.44}$), and the equatorial plane of the host star, and discuss scenarios that could explain both this and the planet’s high density, including secular interactions with other bodies in the system or a giant impact. We note that a significantly misaligned orbit for planet c is in some degree of tension with the dynamical stability of the system, and with the fact that we see both planets in transit, though these arguments alone do not preclude such an orbit. Further observations would be highly desirable to constrain the spin–orbit angle of planet c more precisely.
- Spanish National Research Council Spain
- Space Sciences Laboratory United States
- University of St Andrews United Kingdom
- Sorbonne University France
- College of New Jersey United States
Stars: activity, Aérospatiale, astronomie & astrophysique, 103003 Astronomie, planets and satellites: dynamical evolution and stability, AU Mic c, Physique, chimie, mathématiques & sciences de la terre, FOS: Physical sciences, [SDU] Sciences of the Universe [physics], 103003 Astronomy, techniques: photometric, planets and satellites: dynamical evolution and stability; planets and satellites: formation; stars: activity; stars: individual: AU Microscopii; techniques: photometric; techniques: radial velocities, Physical, chemical, mathematical & earth Sciences, stars: activity, techniques: radial velocities, Stars: individual: AU Microscopii, individual: AU Microscopii [Stars], QB Astronomy, planets and satellites: formation, 103004 Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), AU Mic c, QB, Earth and Planetary Astrophysics (astro-ph.EP), Planets and satellites: dynamical evolution and stability, radial velocities [Techniques], young planet, photometric [Techniques], 500, 3rd-DAS, 103004 Astrophysik, dynamical evolution and stability [Planets and satellites], 520, stars: individual: AU Microscopii, Planets and satellites: formation, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], Techniques: radial velocities, Space science, astronomy & astrophysics, misaligned orbit, Astrophysics - Instrumentation and Methods for Astrophysics, formation [Planets and satellites], activity [Stars], Techniques: photometric, Astrophysics - Earth and Planetary Astrophysics
Stars: activity, Aérospatiale, astronomie & astrophysique, 103003 Astronomie, planets and satellites: dynamical evolution and stability, AU Mic c, Physique, chimie, mathématiques & sciences de la terre, FOS: Physical sciences, [SDU] Sciences of the Universe [physics], 103003 Astronomy, techniques: photometric, planets and satellites: dynamical evolution and stability; planets and satellites: formation; stars: activity; stars: individual: AU Microscopii; techniques: photometric; techniques: radial velocities, Physical, chemical, mathematical & earth Sciences, stars: activity, techniques: radial velocities, Stars: individual: AU Microscopii, individual: AU Microscopii [Stars], QB Astronomy, planets and satellites: formation, 103004 Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), AU Mic c, QB, Earth and Planetary Astrophysics (astro-ph.EP), Planets and satellites: dynamical evolution and stability, radial velocities [Techniques], young planet, photometric [Techniques], 500, 3rd-DAS, 103004 Astrophysik, dynamical evolution and stability [Planets and satellites], 520, stars: individual: AU Microscopii, Planets and satellites: formation, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], Techniques: radial velocities, Space science, astronomy & astrophysics, misaligned orbit, Astrophysics - Instrumentation and Methods for Astrophysics, formation [Planets and satellites], activity [Stars], Techniques: photometric, Astrophysics - Earth and Planetary Astrophysics
selected citations These citations are derived from selected sources.This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).10 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Top 10% influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Average impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Top 10%
Citations provided by BIP!Popularity provided by BIP!