Published online by Cambridge University Press: 04 August 2017
A brief survey is made of recent 21-cm and optical observations of the Magellanic Stream(MS). The space orientation of the Magellanic Clouds is touched upon in relation to modelling the MS. After summarizing a variety of models for the MS, we show that if our Galaxy is massive with a huge dark halo, a tidal model is most suitable for reproducing its characteristic structure and high-negative radial velocity. Past orbits of the Large and the Small Magellanic Cloud (LMC and SMC) are determined uniquely for the last 2×109 yr, if we postulate that the LMC and SMC are bound together for 1010 yr: Highly-noncircular motion of the SMC around the LMC could give a clue to understand some peculiar features associated with the Magellanic Clouds.