19 March 2022 | New Scientist | 19THE reason for the bubblegum
pink colour of a remote lake in
Western Australia has long been
a mystery, but new research
suggests it is caused by a mix
of colourful microbes.
Lake Hillier on Middle Island in
Australia is about eight times saltier
than the ocean. Scott Tighe at the
University of Vermont in Burlington
and his colleagues analysed water
and sediment samples using
metagenomics to sequences all the
DNA in the environmental samples.
They found that the lake
contains almost 500 types of
extremophiles – organisms that
thrive in extreme environments –
including bacteria, archaea, algae
and viruses (bioRxiv, doi.org/hkmh).
Many of them produce purple,
red and orange pigments known
as carotenoids, which may
provide some protection against
extreme saltiness and provide
the water’s colour, says Tighe. ❚
Microbiology
Alice Klein
Pink lake mystery solved
DNA sequencing identifies microbes that colour Australian landmark
TOURISMWEST
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IANews
Technology
Crash-avoiding drones can fly in mines
PROTOTYPE drones that are
capable of navigating dangerous
and unpredictable environments
could prove to be valuable for
search-and-rescue teams.
RMF-Owl, a drone created by
Paolo De Petris at the Norwegian
University of Science and
Technology and his colleagues,
made its debut while winning
a competition hosted by the
US Defense Advanced Research
Projects Agency. This involved
navigating around a mine and
performing rescue-related tasks.
The drone, which dodges
collisions by using laser mapping
and onboard algorithms, can
also work with other flying and
walking robots as part of a team.
“If the robot crashes in the
middle of a passage, which is
really [narrow], then all the other
robots that come afterwards will
be blocked and cannot proceed
in their navigation, so we wanted
to avoid that,” says De Petris.
The flying drone weighs about
1.5 kilograms and has a resilient
carbon-foam frame in case its
collision-avoidance system
fails. However, no such failure
occurred during its tests
(arxiv. org/abs/2202.11055).
“It’s an impressive capability,”
says Raphael Zufferey at the Swiss
Federal Institute of Technology
in Lausanne. “They travel quite
a long distance inside of a mine
without having any collisionsand by generating their own map
and moving within their map.”
Ricardo de Azambuja at
Montreal Polytechnic in Canada
and his colleagues, meanwhile,
have taken a different approach
to avoiding drone crashes.Inspired by the flexible
exoskeletons of insects, they
designed the CogniFly, a small,
autonomous drone weighing
around 250 grams that can survive
repeated high-impact collisions
(arxiv.org/abs/2103.04423).
“We were doing experiments
and mostly we were crashing
[the drone] against the floor,
so we needed something to
absorb the crash landings,”
says Azambuja.
The team has designed a shell
that absorbs landing impacts like
a cricket’s legs, with the drone
being built from 3D-printed parts
and having flexible joints. It could
be used in cave exploration. ❚
Alex WilkinsThe RMF-Owl uses laser
mapping and algorithms
to dodge collisionsDEPETR
IS^ ET^ AL.