At Voyager 1's velocity, it would take ~456 million years to reach the heart of the Milky Way (Sagittarius A*), some ~26,000 light-years away. That's roughly the same amount of time that has passed since the Ordovician–Silurian extinction, when volcanic eruptions released enough carbon dioxide to heat up the planet and deoxygenate the oceans, resulting in the asphyxiation of aquatic species (about 85% of all life was snuffed out). The oceans remained deoxygenated for more than three million years.