The longest animal mission in space has concluded and a group of mice involved in the mission are back on Earth.

"Astronauts experience around 20 to 30 per cent bone loss," the New Scientist quoted Sara Tavella at the University of Genoa in Italy as saying.
She added that while astronauts take different steps to minimise such damage, its difficult to return the bone to its original state back on Earth.
To find ways to address this problem, Tavella's team sent six mice up to the International Space Station. Half of them were genetically modified to produce more of a protein involved in bone development, called pleiotrophin or PTN.
These mice were found to have lost only 3 per cent of the volume of their spine while normal mice suffered a 41.5 per cent decrease.
Tavella says the protein treatment could be investigated for astronauts preparing for space.











