knowledge into what was seen at the
time as a wild surmise. The facts he
combined were that the sun is made up
mostly of hydrogen, with some helium,
and that E=mc^2.
Eddington noticed that four hydro-
gen atoms weigh a tiny bit more than
one helium atom. If four hydrogen nu-
clei somehow fuse together, in a series
of steps, and form helium, then a little
bit of mass must be “lost” in the process.
And if one takes seriously that most fa-
mous of equations, then that little bit of
mass becomes a lot of energy—as much
energy as that amount of mass multi-
plied by the speed of light, squared. To
give a sense of this ratio: If you con-
verted a baseball into pure energy, you
could power New York City for about
two weeks. Maybe that process—hydro-
gen crashing into hydrogen and form-
ing helium, giving off an extraordinary
amount of energy in the process—was
how the sun and all the stars burned so
bright and so long. Eddington, in a paper
laying out this theory, closed with an
unusual take on the story of Daedalus
and his son Icarus. Eddington argued
in defense of Icarus, saying it was bet-
ter to fly too high, and in doing so see
where a scientific idea begins to fail, than
it was to be cautious and not try to fly
high at all.
When most people think of nuclear
energy, they are thinking not of fusion
but of fission. Fission is when an atom—
most commonly uranium or pluto-
nium—breaks in two. Fission generates
waste that remains radioactive for tens
of thousands of years; in contrast, the
little bit of waste that fusion generates
remains radioactive for only a few de-
cades. Fission is pretty powerful, as ev-
idenced by atomic bombs; fusion is
much, much more powerful. (In 1952, a
fusion bomb, known as the H-bomb,
was tested, though it has never been
used in warfare; it worked by using a
fission bomb to set off a giant uncon-
trolled fusion reaction. One of the fa-
thers of the H-bomb, Edward Teller, an
aggrieved Shakespearean villain in most
tellings, had other incautious ideas, such
as using fusion bombs to dig canals or
make diamonds.) The process of fusion
sounds dangerous to a layperson—a sun
in a magnetic bottle?—but it is easier
to extinguish than a match.
The allure of fusion has attracted
brilliant, imaginative minds; it has also
attracted a crowd of shysters, cranks,
and false messiahs. In 1951, Juan Perón,
Argentina’s President, announced that
the country had harnessed fusion en-
ergy. It would soon be available in litre
and half-litre bottles, like milk. Perón
had made the mistake of distrusting
his own country’s scientific commu-
nity, instead putting his faith in Ron-
ald Richter, an Austrian immigrant
whose apparatus, when inspected by
scientists, didn’t even have a functioning
Geiger counter, the device he was using
to claim evidence of fusion radiation.A few decades later, two respected
chemists at the University of Utah, Stan-
ley Pons and Martin Fleischmann, con-
vinced the public that they had produced
nuclear fusion at room temperature, in
what looked like a jar with a little mixer
stick in it. They announced their results
in a press conference before they pub-
lished their data or methods. Pons and
Fleischmann were featured on the cover
of Time. Meanwhile, the work of Steven
Jones, a respected physicist at Brigham
Young University, was also receiving press
attention; he, too, was working on pro-
ducing fusion at a low temperature, and,
though he seemed to be on a promising
path, he was ultimately unsuccessful.
When Pons and Fleischmann finally
published a paper, they were suspected
of having fudged their data. No one was
able to reliably reproduce their results.
Jones later turned to proving that Jesus
had visited Mesoamerica, and after that
to explaining that the destruction of the
World Trade Center was an inside job.
Zach Hartwig, now a professor of nu-
clear science and engineering at M.I.T.
and part of the ARC/SPARC team, has
said, “The biggest problem in fusion is
perception. It’s the perception that fu-
sion is a joke.”
Estimates of the cost of the Man-
hattan Project, which produced atomic
weapons in four years, vary, but it is
commonly said that the scientists were
given a “blank check.” This year, the
U.S. government will spend some six
hundred and seventy million dollars on
nuclear fusion. That’s a lot of money,
but six hundred and fifty billion—the
amount the I.M.F. estimates that U.S.
taxpayers spent on fossil-fuel subsidies
last year—is quite a bit more.
During the oil crisis of the nine-
teen-seventies, fusion research briefly
received the sort of funding that goes
to national-defense projects. M.I.T.’s
Plasma Fusion Center was established
in 1976. The Joint European Torus, at
the Culham Center for Fusion Energy,
in the United Kingdom, which has
heated hydrogen to temperatures hot-
ter than the inside of the sun, began
operating in 1983, and by 1997 had set
important records, some still not sur-
passed. “It was such an exciting time,”
Michael Mauel, a professor of applied
physics at Columbia University, who
“Anything else while I’m there, or just the stick?” did his undergraduate and graduate