68 DISCOVERMAGAZINE.COMNASA/JPL- CA
LTECHBY NOLA TAYLOR REDDdiscovered the object played it safe
and classified their newfound world,
dubbed HD 114762b, as an obscure
type of pseudo-star. A few years later,
astronomers discovered two worlds
orbiting another star, a pulsar named
PSR 1257+12, and that was that — the
era of uncertainty was over and the first
exoplanets had been found, destined for
the history books.
But what if that history is wrong? While
the two pulsar planets got all the glory, the
real first exoplanet may have languished
in obscurity: New data and better instru-
ments mean astronomers are increasingly
suspicious they made the wrong call about
HD 114762b all those years ago.
“It’s the story of people’s advancing
knowledge and changing ideas,” says
David Latham, senior astronomer at
Harvard University and co-discoverer of
HD 114762b. This isn’t a matter of per-
sonal glory for him. It’s simply a question
of scientific legacy.A WHOLE NEW WORLD
In the 1980s, astronomers started figuring
out how to find planets orbiting other stars
— assuming any such worlds even existed.
The limits of optical telescopes made it
essentially impossible to spot such a world
visually; even today’s instruments can see
only the biggest and nearest exoplanets.
So researchers took another approach:
They began to hunt for the effect such a
world might have on its parent star. One
popular method involved looking for the
gravitational tug that a planet might exert
on its sun as the world moves in its orbit.
Find a star wobbling around in place, and
you’ve likely found an exoplanet nearby.
These searches weren’t easy. In those
early years of hunting, a handful of
initial discoveries came and went, each
announcement of a new world retracted
when follow-up observations revealed
errors, both human and instrumental.
Exoplanet claims were met with growing
doubt, and astronomers learned to tread
lightly before announcing a new find.
In this environment of disbelief,
Latham and his planet-hunting colleague,
Tsevi Mazeh of Tel Aviv University, beganThe Fight for
First Exoplanet
Astronomers are almost ready to declare
the winner of a decades-old planetary race.Exoplanets, nowadays, are commonplace. Impossibly hot
gas giants, rocky super-Earths and prolific seven-planet
systems have captivated scientists and the public alike. So it
may be hard to remember only 30 years ago, when every new
claim of a world outside the solar system was revolutionary and
met with disbelief.
In that uncertain era, one massive object danced along the
boundary between planets and stars. The astronomers whoO«
OUT THERE
The object known
as HD 114762b,
illustrated above,
was originally
classified as a type
of star — but it may
be the first exoplanet
we ever spotted.