We present simultaneous photometric and spectroscopic observations of HD17156b spanning a transit on 2007 November 12 (UT). This system is of special interest because of its 21 d period (unusually long for a transiting planet) and its high orbital eccentricity of 0.67. By modeling the Rossiter–McLaughlin effect, we find the angle between the sky projections of the orbital axis and the stellar rotation axis to be $62^{\circ} \pm 25^{\circ}$. Such a large spin-orbit misalignment, as well as the high eccentricity, could be explained as a relic of a previous gravitational interaction with other planets.

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The F0 V star 9 Aur A exhibits an irregular variability of amplitude ≈0.1 magnitude at optical wavelengths. The variations are too slow for it to be a δ Scuti-type star. There is no evidence for a close, interacting companion or ring of dust, either from infrared, ultraviolet, or speckle data.

With the aim of examining how much information of solar rotation can be obtained purely spectroscopically by observing the Sun-as-a-star during the 2012 May 21 eclipse at Okayama Astrophysical Observatory, we studied the variation of radial velocities (Vr), which were derived by using the iodine-cell technique based on a set of 184 high-dispersion spectra consecutively obtained over a time span of ∼ 4 hr. The resulting Vr(t) was confirmed to show the characteristic variation (Rossiter–McLaughlin effect) caused by time-varying visibility of the solar disk. By comparing the observed Vr(t) curve with the theoretical ones [which were simulated with the latitude (ψ) dependent solar rotation law ωsidereal(ψ) = A + B sin 2ψ (degree d−1)] we found that the relation B ≃ −5.5A + 77 gives the best fit, though separate determinations of A and B were not possible. Since this relationship is consistent with the real values known for the Sun (A ≃ 14.5, B ≃ −2.8), we may state that our analysis yielded satisfactory results. This consequence may provide the prospect of getting useful information on stellar rotation of eclipsing binaries from radial-velocity studies during eclipse, if many spectra of sufficiently high time-resolution are available.

We report the detection of δ Sct type variations in the eclipsing binary system, IK Vir (V=11.54 mag, A6, P orb = 0.72 d, Velichko et al. 1991 andKazarovets et al. 1993), in our V-band photometry. The observations were carried out with Moravian G2-1600 CCD camera attached to 28 cm Schmidt-Cassegrain telescope at Akazawa Funao Observatory. Total observational runs are twenty one nights from March 26 to May 26 in 2015. IK Vir is measured differentially to BD+02 2522 = GSC 0281-0223 as the comparison star. BD+02 2522 is measured to GSC 0281-0255 as the check star. All the data in this observational season are shown in the lower light curve in Figure 1. To highlight short period (about 30 minutes) variations, data from only five observing runs, chosen so that there is no overlap in the same phase range, are plotted in the upper light curve in Figure 1. All the V-band photometric data obtained for this study are available as electronic tables(6211-t3.txt) from IBVS website.The light curves in Fig. 2 for three individual nights show beat phenomena, which suggests that the variations are multiply periodic. In order to extract short period variations, third-order polynomials are fitted and subtracted from data for eight nights runs which covered out-of-eclipse phases.The residuals are analysed by the Period4 program (Lenz and Breger, 2005). The first six dominant frequencies are listed in Table 1 and their power spectra at each subtraction phase are shown in Fig. 3. The over-plotted solid line in Fig. 2 shows the light curve synthesized from the detected multiple periods.When we tried to subtract the synthesized light curve from observational data, the short period variations were naturally cancelled in the residuals out-of-eclipse. However, in the period between the phase of about -0.15 to 0.15 covering the primary eclipse, the short period variations could not well cancelled (Fig. 4). This indicates that the pulsating component is the primary and it might indicates that nonradial oscillations of a specific low order mode are emphasized by the eclipse and that some phase shift has occurred (Unno et al. 1989). The new times of minima obtained in 2015 are listed in Table 2. Together with the times of minima listed in the O-C Gateway 1 since 1999, a new ephemeris for primary minimum could be calculated as follows:HJD Min = 2451275.3649312(1) + 0.7236021(2) × E