日本的一艘收集太阳系起源信息的太空探测器历时3年半，向太空深处航行了3亿公里之后，飞抵一颗小行星。
日本宇宙航空研究开发机构说，“隼鸟二号”探测器星期三飞到距离小行星龙宫20公里的位置。这艘探测器将花18个月的时间拍摄小行星龙宫的图片。这颗小行星以日本古代传说中的海底宫殿命名。探测器还要向小行星放出一个法国和德国联合制造的登陆器，研究小行星的表面。
隼鸟二号探测器最终也会降落到小行星龙宫的表面。它将先释放一个装置，把一个两公斤重的铜块发射到小行星表面，形成一个形状像火山口的小撞击坑，然后在那附近降落，收集表面被撞击出来的物质。
隼鸟二号定于2020年年底返回地球。
A Japanese space probe has arrived at an asteroid after a three-and-a half year, 300 million kilometer journey through deep space to collect information about the origins of the solar system.
The Japanese Aerospace Exploration Agency says the Hayabusa2 probe entered into a position about 20 kilometers above the Ryugu asteroid Wednesday. The probe will spend the next 18 months taking photographic images of Ryugu, which is named after an undersea palace in ancient Japanese folklore, and deploy a French-German built lander to study the surface.
Hayabusa2 will eventually land on Ryugu itself during the mission. It will send out a device that will shoot a 2-kilogram copper projectile into the surface that will create a small crater. The probe will land near the surface and collect the underground material blown out of the crater.
Hayabusa2 is due to return to Earth in late 2020.