A cosmic mystery is uniting monks and scientists in Japan after a cherry tree grown from a seed that orbited the Earth for eight months bloomed years earlier than expected—and with very surprising flowers.
The four-year-old sapling—grown from a cherry stone that spent time aboard the International Space Station (ISS)—burst into blossom on April 1, possibly a full six years ahead of Mother Nature's normal schedule.
Its early blooming baffled Buddhist brothers at the ancient temple in central Japan where the tree is growing.
"We are amazed to see how fast it has grown," Masahiro Kajita, chief priest at the Ganjoji temple in Gifu, told AFP by telephone.
"A stone from the original tree had never sprouted before. We are very happy because it will succeed the old tree, which is said to be 1,250 years old."
The seeds were sent to the ISS as part of "an educational and cultural project to let children gather the stones and learn how they grow into trees and live on after returning from space," said Miho Tomioka, a spokeswoman for the project's organiser, Japan Manned Space Systems (JAMSS).
"We had expected the (Ganjoji) tree to blossom about 10 years after planting, when the children come of age," she added.
Kaori Tomita-Yokotani, a researcher at the University of Tsukuba who took part in the project, told AFP she was stumped by the extra-terrestrial mystery.
"We still cannot rule out the possibility that it has been somewhat influenced by its exposure to the space environment," she said.
Tomita-Yokotani, a plant physiologist, said it was difficult to explain why the temple tree has grown so fast because there was no control group to compare its growth with that of other trees.
She said cross-pollination with another species could not be ruled out, but a lack of data was hampering an explanation.
"Of course, there is the possibility that exposure to stronger cosmic rays accelerated the process of sprouting and overall growth," she said.
"From a scientific point of view, we can only say we don't know why."