5 October 2019 | New Scientist | 27climate could swiftly revert to the
icy conditions that had prevailed
during previous advances of an
ongoing ice age.
From time to time, there
was some discussion about the
possible impact of industrial air
pollution on climate, but this
wasn’t a formal part of the course,
and it certainly didn’t seem to
dominate the thinking of my
lecturers at the time.
Far from supporting climate
deniers, as Stern suggests it does,
I think the fact that this former
interpretation of the prevailing
climate has been so unequivocally
rejected only adds to the strength
of the scientific consensus about
anthropogenic climate change.
Not everyone benefits
when drivers become safer
7 September, p 20
From David Holdsworth,
Settle, North Yorkshire, UK
You give figures for road traffic
casualties, without distinguishing
between those who were in a
vehicle and other victims. You
also report a claim that advanced
driver assistance systems could
have the same kind of effect on
fatality rates as the introduction
of seat belts. But for whom? Some
suggest that the UK’s introduction
of seat belts increased the risk to
cyclists and pedestrians.
We suspect we’re addicted
to reading and writing
14 September, p 42
From Hilary Gee,
Grange-over-Sands, Cumbria, UK
I sometimes joke about being
a print addict, and now I see
disturbing similarities between
my reading habit and the
behavioural addictions that Moya
Sarner discusses. I look up and
find I am somehow still reading
at 4 am. I experience a “flow state”
and am uneasy if deprived.
Reading blanks out unhappiness,
pain, misery and illness.
I feel compelled to read any
print – yes, including cereal
packets. While reading, I am
almost totally unaware of
anything outside of the story.
I have a house full of books and
keep a spare e-reader handy.
Of course, pursuing an
academic career has allowed me
to use this tendency quite a bit.
And no, I don’t plan to go to rehab.From Brian Horton, West
Launceston, Tasmania, Australia
Reading about addictions
to behaviours, I realise I have
become addicted to writing letters
to New Scientist. I scan each issue,
looking for some topic that I
can pretend to be an expert in.
As your article points out,
unpredictable rewards strongly
increase the addiction, and you
contribute to this by only rarely
accepting my letters. When each
issue arrives, I scan it quickly to
see if I have been published, then
get grouchy and irritable when no
letter is there or euphoric on the
occasions when my letter appears.
I could possibly fix this
addiction by cancelling my
subscription, but I can’t because
the rest of my family is addicted
to reading New Scientist.^ ❚For the record
❚ The earliest of our photos of the
Mer de Glace glacier was taken in
1919 (21 September, p 8).
❚ The United Nations definition
of “extreme poverty” is an income
of US$1.90 per person per day
adjusted to 2011 purchasing
power parity (7 September, p 46).
❚ Flaming hell. Harold Gasson
was employed by the Great
Western Railway to stoke fires,
not extinguish them (Feedback,
14 September).20 years ago, New Scientist
reported on NASA’s embarrassing
loss of a Mars orbiter“TO LOSE one Martian
orbiter may be regarded as
a misfortune,” we wrote on
2 October 1999, trotting out the
old Oscar Wilde quote. “To lose a
second looks like carelessness.”
The barb was prompted by
NASA’s second loss of a probe at
the doorstep of Mars in six years.
“The Mars Climate Orbiter was
supposed to enter an orbit that would have brought it
no closer than 155 kilometres from the surface, after
a course-altering rocket burn on 15 September,” we
reported. “The burn went according to plan. Yet the
craft descended to within 57 kilometres of the planet’s
surface, where it could not withstand the friction
caused by the Martian atmosphere.” The agency had
previously lost contact with its $1 billion Mars Observer
probe three days before orbital insertion in 1993.
We speculated that the two events might be
connected. The loss of the Mars Observer had helped
drive a switch to cheaper, more frequent missions.
“We’ve been saying all along they were going to lose
one of these things,” said an unnamed NASA scientist
after the second incident. Peter Smith at the University
of Arizona, principal investigator for the Mars Polar
Lander, agreed. “With ‘faster, better, cheaper’ you
work your people to death,” he said.
Such fears were underlined in our 9 October
1999 issue, which revealed the exact reason for
the Climate Orbiter fiasco. It was “a result of a
mistake that would shame a first-year physics
student – failing to convert Imperial units to metric”,
we wrote. Behind this was a clash between spacecraft
engineers and navigation specialists, according to
NASA spokesperson Mary Hardin. “Propulsion people
talk in pound-seconds of thrust and navigators
talk in newton-seconds,” she said.
The result was erroneous data from the orbiter’s
attitude-control system, which was crucial for guiding
the rocket burn. Stressed mission controllers had failed
to notice the discrepancy. “Everyone on NASA projects
is incredibly overworked, and mistakes are happening
not just because we’re faster, but because we’re
working nights and weekends,” said Jonathan
McDowell, an astronomer at the Harvard-Smithsonian
Center for Astrophysics in Cambridge, Massachusetts.
Fortunately, subsequent Mars orbiters have made it
the final few kilometres. Simon IngsTo find more from the archives, visit
newscientist.com/old-scientistViews From the archives
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