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Planet hunt finds
lots of little ones
By Nadia Drake
Planet hunters have unlocked a treasure chest of alien worlds: more than 50
planets, at least 16 not much bigger than
Earth, including one small, sparkling
nugget: a 3.6-Earth-mass planet parked
just inside its star’s life-friendly zone.
“We can say that most of the stars have
planets, and most of them have low-mass
planets,” says astronomer Francesco
Pepe, a member of the Geneva Observatory’s HARPS team that presented the new
finds September 12 during the Extreme
Solar Systems conference in Moran, Wyo.
HARPS finds distant worlds by focusing on wobbly stars pulled in different
directions by orbiting bodies, causing a
Doppler shift in the color of the starlight.
The update brings the team’s eight-year
The super-Earth HD 85512b (illustrated here) is one of more than 50 newly
discovered exoplanets announced September 12 by the Swiss-led HARPS team.
discovery total to more than 150 planets.
A paper to appear in Astronomy &
Astrophysics presents the team’s
description of its planetary population
and suggests that more than 50 percent
of sunlike stars sport a planet. The latest
planet dump suggests that roughly 70 to
80 percent of low-mass planets — with
masses bet ween Earth’s and Neptune’s —
might live in multiplanet neighborhoods.
“We can see that most stars have plan-
etary systems, probably like our own,”
says astronomer Debra Fischer of Yale
University. “This paper is a home run hit
for the Geneva team.”
The new collection suggests that lighter
planets are more common in extrasolar
systems than heavier Jupiter-like ones.
Astronomers predict Earth-sized planets
will be yet more common.
Hints of a flaw in special relativity
Neutrinos exceed speed of light, but physicists stay skeptical
By Devin Powell
An experiment with neutrinos has called
into question Einstein’s theory of special relativity. Physicists working on
Italy’s OPERA experiment say they have
clocked the neutrinos traveling faster
than the speed of light.
Few experts believe that this result will
ultimately hold up. But according to the
OPERA team’s calculations, there’s only
a one in a billion chance that the finding
is a statistical fluke, the team announced
on September 23 at the European physics
laboratory CERN near Geneva.
“This will be a tremendous revolu-
tionary finding if it is true,” says Chang
Kee Jung, a particle physicist at Stony
Brook University in New York. But he
says he’d bet his house that it isn’t.
at either end synchronized by a satellite.
Still, the team may have missed some
unknown uncertainties built into their
equipment, says Kevin McFarland, a
particle physicist at the University of
Rochester in New York.
“It’s just odd,” he says. “Everybody’s
bias in responding to this is going to be
that this is some sort of systematic uncer-
tainty that they didn’t figure out.”
This isn’t the first report of super-
luminal neutrinos. In 2007 the MINOS
experiment turned up hints of neutrinos
traveling impossibly fast between
Fermilab, in Batavia, Ill., and a mine in
Minnesota. But the uncertainties in those
measurements were large.
MINOS will soon upgrade its equipment with new atomic clocks, says
Fermilab physicist Rob Plunkett. The
upgraded experiment will start in 2013
and last for a year or so.