Distance covered: 36,796 km (22,864 miles)
Subjects found: 77
Yesterday, we were told she'd passed away.
We found her today, very much alive.
It was a bitterly cold morning, with ice still on the ground from last night's hailstorm, as Moreno and I went hunting for clues. Countless locals shook their heads at her portrait before someone finally seemed to recognise her.
This time, they were pointing not at the sky, but somewhere down here on Earth. We followed the indications across the plains to a small grey stone house by the side of the road - and there she was.
Ayong is 78 years old, with four grown children, a great toothless grin, and no yaks. Here on the Tibetan plateau, a yak is a very good thing to have - for its milk, butter, meat and hide - and a yakless life is not an easy one.
Ayong's sons - like almost everyone, it seems - are in the mountains in search of the famed caterpillar fungus...
Following a clue from the local temple, Moreno and I rented a motorbike and rode an hour south to a tiny village tucked away amongst the mountains.
There we found 62-year-old Zen Ga, who took us into her kitchen to feed us and proudly show us photographs of her children and grandchildren.
When I requested Zen Ga's signature on a release form, explaining that I'd like her permission to use the photographs and videos we'd shot, she told me she could write only numbers, and signed:
361 107 758 88178 638 0 0
She has yaks.
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