The Australian and the American troops have somehow reached Jupiter aliens at the same time. The aliens were trapped with the American troops coming from the north and the Australian troops coming from the south and west. Where could they go. There was only one place to go.
The aliens went running into the water swimming away. The Australian troops were shooting at them, but they were hard to see due to the water being so dirty because a nearby volcano erupted a couple of months ago. Thirty seconds later, all the aliens were visible, on top of the water, dead. They had breathed and drank a bit of the water while they were swimming, which means the were putting poisen from the volcano into their bodies.