This is just too cool. You’re watching a time-lapse of the the kilometer-wide asteroid Ryugu spin on its axis. One complete rotation takes 7.6 hours or about one typical work shift. How many Ryugu rotations have you worked for the man this month?
If you have a pair of red-blue glasses 3D glasses, put them on to see it spin in three dimensions; it looks even more amazing. The asteroid’s equatorial ridge really sticks out. And what is that giant, white block at the top? Obviously a huge boulder, but why so white? Is its composition different from the darker parts of the asteroid?
The animation is compiled from sequential images taken by the Japanese Hayabusa 2 spacecraft during the final approach to Ryugu on June 23. Photos were captured every 10° of rotation with the probe about 24 miles (40 km) away.
Hayabusa 2 arrived at the little asteroid on June 27 and will commence scientific studies soon from its hovering orbit of 12 miles (20 km). From the shifting of the radio waves transmitting by the spacecraft, mission controllers could tell that it was feeling the gravity of the asteroid. At the end of this month, the probe will descend to just 3 miles (5 km) above the surface for medium-altitude observations.
In case you wondered, the name Ryugu means Dragon Palace, a magical underwater palace described in a Japanese folktale. In the story, the a fisherman travels to the palace on the back of a turtle and returns with a mysterious box, much like Hayabusa 2 has traveled to a distant asteroid and will return to Earth in December 2020 with samples taken from both its surface and at depth. Magic indeed!