r odd
things, including fractions of Planck's constant."

A couple of the correspondents--a man from La Prensa, and an
Australian--whistled softly. The others looked blank. Pitov took over:

"You see, gentlemen, most of what we learned, we learned from putting
negamatter atoms together. We annihilated a few of them--over there in
that little concrete building, we have one of the most massive steel
vaults in the world, where we do that--but we assembled millions of them
for every one we annihilated, and that chunk of nega-iron inside the
magnetic bottle kept growing. And when you have a piece of negamatter
you don't want, you can't just throw it out on the scrap-pile. We might
have rocketed it into escape velocity and let it blow up in space, away
from the Moon or any of the artificial satellites, but why waste it? So
we're going to have the rocket eject it, and when it falls, we can see,
by our telemetered instruments, just what happens."

"Well, won't it be annihilated by contact with atmosphere?" somebody
asked.

"That's one of the things we want to find out," Pitov said. "We estimate
about twenty percent loss from contact with atmosphere, but the mass
that actually lands on the target area should be about forty kilos. It
should be something of a spectacle, coming down."

"You say you had to assemble it, after creating the negative protons and
neutrons and the positrons. Doesn't any of this sort of matter exist in
nature?"

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