The man who asked that knew better himself. He just wanted the answer on
the record.

"Oh no; not on this planet, and probably not in the Galaxy. There may be
whole galaxies composed of nothing but negamatter. There may even be
isolated stars and planetary systems inside our Galaxy composed of
negamatter, though I think that very improbable. But when negamatter and
posimatter come into contact with one another, the result is immediate
mutual annihilation."

They managed to get away from the press, and returned as far as the
bunkers, a mile and a half away. Before they went inside, Richardson
glanced up at the sky, fixing the location of a few of the more
conspicuous stars in his mind. There were almost a hundred men and women
inside, each at his or her instruments--view-screens, radar indicators,
detection instruments of a dozen kinds. The reporters and telecast
people arrived shortly afterward, and Eugenio Galvez took them in tow.
While Richardson and Pitov were making their last-minute rounds, the
countdown progressed past minus one hour, and at minus twenty minutes
all the overhead lights went off and the small instrument operators'
lights came on.

Pitov turned on a couple of view-screens, one from a pickup on the roof
of the bunker and another from the launching-pad. They sat down side by
side and waited. Richardson got his pipe out and began loading it. The
loudspeaker was saying: "_Minus two minutes, one fifty nine, fifty
eight, fifty seven_--"

He let his mind drift away from the test, back to the world that had