Free Astronomy Magazine November-December 2018

13 NOVEMBER-DECEMBER 2018 SMALL BODIES to study a new area of the surface. Before stop- ping its activity, MAS- COT analyzed several sites during more than two asteroid rotations (over 17 hours in total), collecting images and data on the composi- tion, structure, and the magnetic and thermal properties of Ryugu. Each recording was transferred to the Ha- yabusa2 computer be- fore the MASCOT bat- tery depletion and then retransmitted back to the Earth. It will take some time to analyze the vast amount of information collected. On the evening of October 3 rd , the MAS- COT mission was successfully completed and Hayabusa2 returned to its parking po- sition 20 km above the surface of the aster- oid. By the end of October (when this issue of the magazine will be closed) a first con- tact between Hayabusa2 and Ryugu was scheduled, with the explicit goal of collect- ing precious samples of superficial material. The first specimens will be (were, for the reader) collected from a kind of horn that is in contact with the surface, expelling a small projectile consisting of 5 grams of tantalum at a speed of about 300 m/s. Part of the material ejected in the impact will be collected by a “funnel” placed on the top of the horn. In this case, the weak grav- ity of the asteroid also facilitates this oper- ation. Subsequently, Hayabusa2 will collect samples of more in-depth material, which may have remained unaf- fected since the formation of the solar system, and certainly protected from the action of solar wind and cos- mic radiation. To reach that un- derground mate- rial, it will be nec- essary to remove the layer of overly- ing regolith and rock. For this pur- pose, Hayabusa2 will release the Small Carry-on Im- pactor, a sort of cop- per bullet weigh- ing over 2 kg, with O n the right, Rover-1B suc- ceeded in shoot- ing a movie on Ryugu’s surface! The movie has 15 frames captured on September 23, 2018 from 10:34 - 11:48 JST (Japan Standard Time). [JAXA]