Alien DUST found at the bottom of the Earth’s ocean | Daily Mail Online.
The punchline is that regular Supernova may not be sufficient to make the heavier elements, like Uranium and Thorium (U & T), that provide much of Earth’s, and other Solar System objects, their long term radiogenic warming. Of course there’s still Potassium 40 (K-40) in other parts of the Galaxy, but if most Supernova debris contains 1% the expect U & T then there’s something different about the supernova that seeded our Solar System with its radioactive isotopes.