Where oh where has India's moon lander gone? Over a month after Chandrayaan-2's Vikram lander had an unlucky crash landing, somewhere near the unexplored lunar south pole, NASA still can't seem to find any trace of it.
After poring over a new set of images from the space agency's Lunar Reconnaissance Orbiter (LRO), its experts have come up empty-handed for the second time. Comparing images from before and after the crash, they say this region of the Moon appears altogether empty.
A previous fly-by in September gave us no luck either, although at that time the images had been taken at dusk, so there were larger shadows on the terrain.
These might very well have obscured the lander, and yet even in October, when the lighting was supposed to be more favourable, there was nothing to be seen.
"It is possible that Vikram is located in a shadow or outside of the search area," John Keller, the deputy project scientist for the LRO mission, told the Press Trust of India.
"Because of the low latitude, approximately 70 degrees south, the area is never completely free of shadows."
Or maybe we simply aren't looking in the right spot. During it's 'hard' landing, India's space agency lost contact with the lander, and a cold night in this part of the Solar System is a death sentence for human machinery.
A day after the crash, the Indian Space Research Organisation reported it had found the lander in a thermal image of the Moon, so maybe it is hiding in the shroud of a shadow after all.
Earlier this year, another lunar lander called Beresheet from SpaceIL and Israel Aerospace Industries met the same unfortunate fate, but it was eventually found on the surface using the same techniques that experts are currently using.
For now, we'll just have to keep looking.