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risk – and the risk
of communicating
Sue Bowler,
the eventual
outcome of
the judicial
the L’Aquila
earthquake, the conviction of six
scientists and one government
official for manslaughter has
rung alarm bells in all areas
of science where researchers
are expected to forecast events
and assess risk. And, of course,
these are the areas where much
of the science within the remit
of the RAS have the greatest
economic impact. It is not just
earthquakes, but forecasts of
natural hazards, environmental
change and space weather
are increasingly in demand
from government and industry.
The last thing we need is for
researchers to steer away from
working in these commercially
and socially significant fields,
for fear of arrest. Many of the
events that researchers are
seeking to understand and,
where possible, to forecast, are
low probability, high risk events.
The effectiveness of forecasts
can be assessed only by making
the forecasts in real time, and
comparing the outcomes with
the real world. Many forecasts
will be wrong, to a large or small
degree, but avoiding making
them avoids the opportunity to
learn how to improve them.
One of the lessons that has
come out of scientific riskassessment of natural hazards
so far is that rare events happen.
In 1981 Mt St Helens erupted in a
powerful lateral blast caused by
a landslip that took observers by
surprise, not because it had not
been forecast, but because it was
given a probability of just 5% by
A big part of the problem
is the gap between careful
scientific assessment of risk,
and the public dissemination
of that assessment. Better
communication about the
problems involved from everyone
in this process – scientists, the
public, local and national officials
– would be a good first step.
[email protected]
L’Aquila verdict poses risk for science
The conviction of six Italian seismologists for manslaughter following the L’Aquila earthquake has
been met with concern by scientific
bodies around the world.
The scientists may appeal, but the
case raises issues around the assessment and communication of risk that
may seriously affect seismologists,
volcanologists and those working in
space weather, among others.
In a statement, the Royal Astronomical Society deplores the sentences and offers support to all
those involved: “The victims of the
L’Aquila earthquake, and their families, deserve a thorough investigation of all measures taken before the
earthquake. Such an investigation
would also be of immense value to
other communities exposed to seismic hazard in Italy. Instead, the draconian sentences – which have been
handed down to scientists and civil
defence personnel alike – trivialize
the multifaceted problem of identifying, communicating and mitigating seismic hazard, and make future
progress more difficult.”
The risk is that scientists will
choose not to be involved in areas
where real-time evaluation of a
changing situation, and prediction
of future events, is expected by civil
authorities and industrial clients, for
The European Geosciences Union
stressed the potential danger of this
approach: “If scientists stop actively
engaging with the public to demonstrate the importance of their work,
if they refuse to work in hazardevaluation panels, or if they are afraid
of offering scientific advice to the best
of their ability, the prime foundations of science – sharing and openly
HARPS spots nearby exo-Earth
Citizen science
finds planet
precision achieved using this method.
“Alpha Centauri Bb is the first
planet with a mass similar to Earth
ever found around a star like the
Sun. Its orbit is very close to its star
and it must be much too hot for life
as we know it,” said Stéphane Udry
(Geneva Observatory), a co-author
of the paper and member of the team,
“but it may well be just one planet
in a system of several. Our other
HARPS results, and new findings
from Kepler, both show clearly that
the majority of low-mass planets are
found in such systems.”
The discovery was published in
Nature by Xavier Dumusque of
Geneva Observatory and co-authors
and brought congratulations from
NASA, among many others.
● M artin Beech reviews the Alpha
Centauri system on pages 6.10–6.16
of this issue.
The citizen science project Planet
Hunters has discovered the first
planet found in a four-star system.
An international team of astronomers together with volunteers using
the website identified and confirmed the discovery of
this circumbinary planet (PH1) in
a four-star system. The volunteers,
Kian Jek of San Francisco and Robert Gagliano of Cottonwood, Arizona, spotted faint dips in starlight
as the planet made transits.
Meg Schwamb, a Yale postdoctoral
researcher, led the team of professional astronomers that confirmed
the discovery and characterized the
planet, using data from the Keck telescopes on Mauna Kea, Hawaii. PH1
is a gas giant with a radius about 6.2
times that of Earth (a bit bigger than
Neptune) and orbits outside a pair of
eclipsing stars that are 1.5 and 0.41
times the mass of the Sun. It revolves
around its host stars roughly every
138 days. Beyond the planet’s orbit
at about 1000 au is a second pair of
stars orbiting the planetary system.
“Circumbinary planets are the
extremes of planet formation,” said
Schwamb at the annual meeting of
the Division for Planetary Sciences of
the American Astronomical Society
in Reno, Nevada. “The discovery of
these systems is forcing us to go back
to the drawing board to understand
how such planets can assemble and
evolve in these dynamically challenging environments.” The paper has
been submitted to The Astrophysical Journal.
An artist’s impression of the newly discovered planet Alpha Centauri Bb.
(ESO/L Calçada/N Risinger [])
European astronomers have found
a planet with about the mass of the
Earth orbiting a star in the Alpha
Centauri system. The planet, the
lightest exoplanet discovered
around a star like the Sun, was
detected using the HARPS instrument on the 3.6 m telescope at
ESO’s La Silla Observatory in Chile.
Alpha Centauri is a triple star system
only 4.3 light-years away from the
solar system, comprising two stars
similar to the Sun orbiting close to
each other, Alpha Centauri A and B,
and a more distant and faint red component known as Proxima Centauri.
The European team used the
HARPS instrument to detect slight
variations in movement of the star
Alpha Centauri B arising from the
gravitational tug of the planet – the
star moves back and forth by no
more than 51 cm s –1, about the speed
of a baby crawling. This is the highest
discussing research and increasing
knowledge – are no longer met.”
The situation in the case of the
L’Aquila case is complex and
involves both scientific understanding of earthquake risk and the way
in which all those involved communicated that risk to the people who
live and work in the affected region.
The RAS argues for “a sustained
programme of education at all levels of society – the general public,
local authorities, and policy makers
– communicating the nature of the
hazard, the risk to which communities are exposed, and the measures
that can be taken to reduce that risk.
Without such education, advice at a
moment of crisis may well be misunderstood and, in the aftermath of
a disaster, that same advice may be
turned against those who gave it.”
A&G • December 2012 • Vol. 53