It was a tragedy.
The planet, some of whose inhabitants they knew from the scant remaining records had called ‘Earth’, was no longer capable of supporting life.
When they found the cache of cryogenic capsules most were clearly no longer viable, but one remained that was. Taking the last frozen survivor from the long dead world, they left and went home, hoping they might learn much from the ancient sleeper.
It was many rotations later before they could revive their discovery. So there was great excitement and anticipation when the ancient one woke, stretched, shook itself thoroughly and said ‘Woof’.