As humanity dwindled in numbers, the last remaining scientists, philosophers, theologians, and humanitarians got together and began compiling a list of everything humanity had left. They called themselves The Society of Human Archives, and their mission was to preserve humanity's remaining legacy for the distant future. Their prospects were bleak but hopes were high.
At that point, many countries were gone and the once sprawling, prosperous cities were taken back by nature. With it, many archives, museums, libraries were lost to time and their contents had returned to dust. The group only had what they could salvage for physical entries of the list.
Within the next 5 years the group managed to collect the thousands of items on the list. They were labeled, meticulously scrutinized and studied, and put in specially designed seals intended to freeze the item in its state.
They loaded a spaceship with all the items sealed again in an atmospheric chamber capable of shielding the objects from the harsh conditions of space.
On a clear, winter morning the shuttle was launched carrying the remains of humanity. Once the ship reached a specific altitude, rockets blasted orienting the ship to use Earth’s gravity to further propel itself away from the planet. As time passed, the ship’s weak radio signals got engulfed by the deep, roaring background noise of space. As it left the hands of humanity, the group celebrated and parted their ways.
Since that day, all signals from Earth died. A few hundred years later, the last remaining humans died leaving small objects and several wall paintings behind. Those too withered away with time and thousands of years later, they were mostly gone. Some thousands of years later the planet was struck by an unpredicted meteor which vaporized the planet’s surface. Later, it was swallowed by the dying sun as it’s internal, hydrogen-based structure collapsed. Nothing remained.
The little spaceship, now lost in time and space, submerged in the eternal darkness remained the only memory of humanity’s once fruitful existence. It too was forever undiscovered.
And that was the end of humanity.