New Scientist - 02.18.2020

(C. Jardin) #1

14 | New Scientist | 8 February 2020

A GROUP of astronomers has
called for legal action to stop
the launch of vast numbers of
satellites designed to beam
high-speed internet around the
world, until their impact on the
night sky can be assessed.
US firm SpaceX has already
launched 240 satellites as part of
its planned Starlink constellation
of up to 42,000 satellites. Others,
such as the UK company OneWeb,
plan to launch hundreds of their
own. There are currently 1500
active satellites orbiting Earth.
Starlink satellites have created
bright streaks in some telescope
images, affecting astronomical
observations. Some worry that the
thousands of bright points of light
could alter the sky for the public
and astronomers forever.
“The ideal thing would be
to stop the deployment of these
kind of satellites until the problem
is very well studied. We have to
understand what the impact is
on the sky,” says Michele Maris at
the Astronomical Observatory of
Trieste in Italy, part of the group
calling for legal action.
To halt mega constellations,

the group says that a case could be
brought to the International Court
of Justice to argue that the night
sky is a shared human right under
the World Heritage Convention.
“The harm here is damage to our
cultural heritage, the night sky,
and monetary damages due to
the loss of radio and other types
of astronomy,” the scientists write
Alternatively, the group says

a case could be filed against
the Federal Communications
Commission (FCC) in the US for
licensing Starlink, which the
astronomers say may have
been in breach of the National
Environmental Policy Act (NEPA).
“It would be desirable to
adopt contingent and limiting
resolutions to be ratified as
shared international rules,” the
astronomers write. They also
suggest that, in the meantime, all
mega constellations should be put
on hold. An associated petition to
temporarily halt further launches

has more than 1400 signatures.
Chris Johnson, a space law
adviser at the Colorado-based
pressure group the Secure World
Foundation, says that the chances
of legal action being successful are
slim, but there is an argument that
could be made.
“It’s time for the larger space
community to think what means
more: ground-based astronomy
and traditional views of the night
sky or cheaper internet from
space,” he says.
The FCC said in a statement it
“strongly reject[ed]” any claims it
has violated NEPA and its approval
of Starlink was “entirely lawful”.
SpaceX has attempted to ease
concerns by testing a Starlink
satellite coated in a darker material
so that it won’t reflect as much
light. However, launches are
ongoing, with SpaceX set to send
up 1500 Starlink satellites in 2020.
“If it is not possible to leave
a better planet for future
generations, we can at least try
not to make it worse,” says group
member Stefano Gallozzi at the
Astronomical Observatory of
Rome in Italy. ❚






SpaceX launched more
Starlink satellites on
29 January

“ When the local
temperature rose, the
pores would simply open
and close on their own”


3D-printed robots
can sweat to cool
themselves down

ROBOTS are becoming more
human-like every day, and
now they can sweat.
Thomas Wallin at Cornell
University in New York and
his colleagues have created soft
robotic grippers that are capable
of sweating to cool down.
The grippers can achieve a
cooling capacity of 107 watts
per kilogram, making them more
efficient sweaters than mammals.

By comparison, humans and horses
have a maximum cooling capacity
of about 35 watts per kilogram.
Each gripper consists of three
finger-like parts that bend
simultaneously to grasp small
objects. The 3D-printed grippers
are made from hydrogels, polymer
materials that can store large
amounts of water. Each finger
has an underlayer with an internal
channel to let fluid flow and
is capped with a surface layer
containing micropores.
At cold temperatures, the pores
close. At temperatures higher than
30°C, the surface layer expands,

dilating the pores and enabling
pressurised fluid from the
underlayer to sweat out. The
material responds spontaneously
to temperature changes without
the need for external sensors
(Science Robotics,
“Sweating takes advantage of
evaporative water loss to rapidly
dissipate heat,” says Wallin. Unlike
convection or radiation, sweating
lowers the temperature of a body

below that of its environment.
“When the local temperature rose
above the transition [temperature],
the pores would simply open and
close on their own,” he says. When
blown by wind from a fan, the
sweating robots cooled at a rate
of 39.1°C per minute, about six
times as fast as similar devices
that are unable to sweat.
However, there is currently no
means to replenish the robot’s fluid
stores after sweating. This means
“the robots would have to also be
able to drink”, says team member
Robert Shepherd, also at Cornell. ❚
Donna Lu


Jonathan O’Callaghan

Astronomers want to halt Starlink

Legal action may be pursued to stop thousands of satellites clogging up the sky

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