As we mentioned in past articles, the Japanese Kaguya spacecraft, now orbiting the Moon, is actually a collection of satellites. The largest satellite is Kaguya. It’s the one equipped with all the cameras and the suite of scientific instruments.
But Kaguya was also carrying two baby satellites. The first Relay satellite, nicknamed Okina, was released on October 9th. Today Kaguya released its second sub-satellite: the tiny Very Long Baseline Interferometer (or VRAD). VRAD’s job will be to help Kaguya carefully map out the Moon’s gravity field.
Original Source: JAXA News Release