The results are presented in Fig. 1 and Table 1. At the moment of writing this paper there are 26 known planetary systems which
contain planets in or close to mean-motion resonances or are suspected of having Tamoxifen datasheet such planets. We do not include here the candidates for planets detected by the Kepler mission, as they still await to be confirmed. The systems are ordered according to the increasing ratio of the orbital periods of the planets in a resonance starting from the system Kepler-11 with two planets close to the 5:4 resonance and closing with HD 208487 with planets in the 7:1 commensurability. In Fig. 1 the planets in a resonance are denoted in red. In Table 1 the planet parameters (their minimal masses m sin(i) and the semi-major axes) are given in boldface. Now, let us have a look at those systems and their properties. Fig. 1 The observed planetary systems in which the mean-motion resonances can be present. The planets reported as being close to the mean-motion commensurability are
selleck screening library marked in red, those not involved in any resonance in blue and the super-Earths in green Commensurabilities with the Ratio of Orbital Periods less than Two Kepler-11 The host star of the system Kepler-11 (KIC 6541920, KOI-157) is a dwarf of spectral type G (Lissauer et al. 2011a). Its effective temperature is of about 5680 ± 100 K, the gravitational acceleration g on the star surface is given by log(g(cm/s2)) = 4.3 ± 0.2, the metallicity is the same as that of our Sun [Fe/H] = 0.0 ± 0.1 dex. (Please note, that from now on we will be using always the same units for the gravitational acceleration and metallicity but they will not be specified explicitly in the text.) The mass and the
ADP ribosylation factor radius of the host star in the system Kepler-11 are M = 0.95 ± 0.10 M ⊙ and R = 1.1 ± 0.10 R ⊙ , respectively. The system is at a distance of about 2000 light years from our Sun (613.5 pc). The age of the star is estimated at about 6 × 109 − 1010 years. On the orbits around this star there are 6 transiting planets. Five of them have their orbital periods in a range from 10 to 47 days (it means they are closer to their host star than Mercury to the Sun). The sixth planet has a longer period that exceeds 100 days. In the previous section (Section “Observations of Extrasolar Planetary Systems”) we have pointed out that with the transit method it is possible to know the size of the planets but not their mass. We have also mentioned the powerful TTV technique, which allows to detect non transiting planets or planets that are too small for their signal to be measured. In the case of Kepler-11, in which all planets are transiting, this technique is able to verify the planetary nature of the observed objects through the evaluation of their masses. In this way the five most internal candidates for planets of this system have been confirmed. HD 200964 The planets are near the 4:3 mean-motion resonance (Johnson et al. 2011).