scholarly journals Multiplanet disc interactions in binary systems

2019 ◽  
Vol 491 (4) ◽  
pp. 5351-5360 ◽  
Author(s):  
Alessia Franchini ◽  
Rebecca G Martin ◽  
Stephen H Lubow

ABSTRACT We investigate the evolution of a multiplanet–disc system orbiting one component of a binary star system. The planet–disc system is initially coplanar but misaligned to the binary orbital plane. The planets are assumed to be giants that open gaps in the disc. We first study the role of the disc in shaping the mutual evolution of the two planets using a secular model for low initial tilt. In general, we find that the planets and the disc do not remain coplanar, in agreement with previous work on the single planet case. Instead, the planets and the disc undergo tilt oscillations. A high-mass disc between the two planets causes the planets and the disc to nodally precess at the same average rate but they are generally misaligned. The amplitude of the tilt oscillations between the planets is larger while the disc is present. We then consider higher initial tilts using hydrodynamical simulations and explore the possibility of the formation of eccentric Kozai–Lidov (KL) planets. We find that the inner planet’s orbit undergoes eccentricity growth for a large range of disc masses and initial misalignments. For a low disc mass and large initial misalignment, both planets and the disc can undergo KL oscillations. Furthermore, we find that sufficiently massive discs can cause the inner planet to increase its inclination beyond 90° and therefore to orbit the binary in a retrograde fashion. The results have important implications for the explanation of very eccentric planets and retrograde planets observed in multiplanet systems.

Science ◽  
2014 ◽  
Vol 345 (6192) ◽  
pp. 46-49 ◽  
Author(s):  
A. Gould ◽  
A. Udalski ◽  
I.-G. Shin ◽  
I. Porritt ◽  
J. Skowron ◽  
...  

Using gravitational microlensing, we detected a cold terrestrial planet orbiting one member of a binary star system. The planet has low mass (twice Earth’s) and lies projected at ~0.8 astronomical units (AU) from its host star, about the distance between Earth and the Sun. However, the planet’s temperature is much lower, <60 Kelvin, because the host star is only 0.10 to 0.15 solar masses and therefore more than 400 times less luminous than the Sun. The host itself orbits a slightly more massive companion with projected separation of 10 to 15 AU. This detection is consistent with such systems being very common. Straightforward modification of current microlensing search strategies could increase sensitivity to planets in binary systems. With more detections, such binary-star planetary systems could constrain models of planet formation and evolution.


2001 ◽  
Vol 200 ◽  
pp. 511-518 ◽  
Author(s):  
Wilhelm Kley

Among the 50 discovered extrasolar planets orbiting main-sequence solar type stars only three are confirmed to be in a binary star system. However, the majority of stars seem to form in binary or even multiple stellar systems. Standard planet formation scenarios consider the creation of planets or planetary systems only for isolated solitary stars. The presence of a companion creates tidal torques on the protoplanetary disk, which may influence the formation process of planets in disks. In this contribution the consequences of the companion's perturbation on the formation scenario of planets is briefly discussed.


Nature ◽  
1942 ◽  
Vol 150 (3810) ◽  
pp. 545-545

Science ◽  
2014 ◽  
Vol 344 (6181) ◽  
pp. 275-277 ◽  
Author(s):  
E. Kruse ◽  
E. Agol

2014 ◽  
Vol 9 (S310) ◽  
pp. 86-87
Author(s):  
D. Bancelin ◽  
E. Pilat-Lohinger ◽  
S. Eggl ◽  
R. Dvorak

AbstractBy now, observations of exoplanets have found more than 50 binary star systems hosting 71 planets. We expect these numbers to increase as more than 70% of the main sequence stars in the solar neighborhood are members of binary or multiple systems. The planetary motion in such systems depends strongly on both the parameters of the stellar system (stellar separation and eccentricity) and the architecture of the planetary system (number of planets and their orbital behaviour). In case a terrestrial planet moves in the so-called habitable zone (HZ) of its host star, the habitability of this planet depends on many parameters. A crucial factor is certainly the amount of water. We investigate in this work the transport of water from beyond the snow-line to the HZ in a binary star system and compare it to a single star system.


2008 ◽  
Vol 387 (2) ◽  
pp. 481-496 ◽  
Author(s):  
N. J. Dunstone ◽  
G. A. J. Hussain ◽  
A. Collier Cameron ◽  
S. C. Marsden ◽  
M. Jardine ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document