The Alaska was a spaceship that crashed into the Dalek Asylum and launched several escape pods to the planet's surface.
There were at least two survivors. One of them was named Harvey, who died soon after on the frigid surface and was reanimated by the nanocloud field, becoming a Dalek puppet along with the other crew members who died on impact. Harvey's body was preserved by the cold, along with his mind, but the crew inside the Alaska degenerated to purely skeletal remains. The other survivor was Oswin Oswald, Junior Entertainment Manager, who was able to use a ladder and descend below the surface of the planet, but was later captured and fully converted into a Dalek.