In order to better understand the dynamical evolution and star formation history of the Magellanic system, realistic N‐body simulations of the tidal distortion of the Small Magellanic Cloud (SMC) as a result of the Galaxy and the Large Magellanic Cloud have been carried out, taking into account gas dynamics and star formation processes explicitly. The best model succeeds in reproducing the observed structural, kinematic and star formation properties of the SMC, including other related tidal features in the Magellanic system, without resorting to the ram pressure model. The best‐fitting simulation reproduced a gas stream with almost no stars and the observed H i gas fraction, for which the morphology and velocity field agree quite well with those of the Magellanic stream, a result of adopting an initial SMC model that has a compact stellar disc embedded in an extended gaseous disc. This implies that the existence of a purely gaseous Magellanic stream does not pose serious problems to a tidal model of formation. Also, in this best model, the central and south‐east side (wing region) of the SMC contained an excess of young stars, as is observed. Comparison with a reference simulation of isolated evolution demonstrated that the acceleration of star formation activity in these regions may be a direct result of the last interaction between the Magellanic Clouds roughly 0.2 Gyr ago, which formed the inter‐cloud region. The large extent in depth of the SMC implied by the spatial distribution of Cepheids, and the line‐of‐sight velocity pattern in H i around the SMC is also reproduced. Finally, the dependences of these results on the numerical parameters that specify the SMC mass model and interstellar gas processes are discussed.

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On September 14, 2007, Moon explorer SELENE (Kaguya) was launched to the Moon carrying a 10-m spatial resolution stereo-camera, the Terrain Camera (TC). Particular mission objectives of the TC include Polar regions and Mare regions such as Oceanus Procellarum, South-Pole to Aitken basin, and Mare Orientale, that have not been observed with TC's high-resolution stereoscopy. The first TC data of the Moon were obtained on Nov. 3, 2007. We confirmed 1) that the TC had not generated any defective pixels and would achieve high signal-to-noise ratio (S/N) performance and 2) that the TC could provide high-quality data in the Polar regions and a 180 km region extending from 60N to 66N along 240E. We could acquire scientific information from ortho images and digital terrain models (DTMs) produced from these TC first data. On Nov. 24, 2007, we acquired several sequential strip data, from which a seamless mosaicked TC ortho image and DTMs were successfully produced. These seamless mosaicked data will be very useful for investigating large mare regions. After completion of the nominal checkout phase on Dec. 21, 2007, the TC began the nominal mission operation phase with other mission instruments. Thus, we could confirm that TC will provide fundamental assets for lunar science from the initial checkout phase data.

The system of the Magellanic Clouds is considered to be dynamically interacting among themselves and with our Galaxy. This interaction is thought to be the cause of many complicated features seen in the Magellanic Clouds and the Magellanic Stream (see Westerlund 1990, A&AR, 2, 27). In order to better understand the formation and evolution of the Magellanic System, we carry out realistic N-body simulations of the tidal distortion of the Small Magellanic Cloud (SMC) due to our Galaxy and the Large Magellanic Cloud (LMC).