Scientists had thought that heavy and stable isotopes should exist.

All heavier isotopes are synthetic and have a half-life less than a zeptosecond (10 second).

The technique had previously been used to isolate heavy isotopes of neon.

Using heavy isotopes to make it last a little longer.

"Well, from the pattern of heavy isotopes in the crust, it looks like the Transmuters processed the atmosphere at least a billion years ago."

There was a planet labeled with heavy isotopes, 270 light years away.

The Hydrons are not found in heavier isotopes, however.

More energy is released forming this isotope than any other, although fusion can form heavier isotopes.

A spinning tube called a rotor propels the heavy isotope to the outside wall and leaves the light one at the center.

The heaviest isotopes are the most stable, with Hs having a measured half-life of about 11 minutes.