Will China’s new laser satellite become the ‘Death Star’ for submarines?
The team has come up with an innovative approach
that has not been tried before.
The device is designed to generate high-power
laser beam pulses in different colours, or frequencies, that allow
sensitive receivers to pick up more information from various depths.
The main target for the satellite was the thermocline – a
thin layer of water where the temperature changes abruptly. The thermocline is known to be
important for submarine captains because it can reflect active sonar and
other acoustic signals. That means a vessel could potentially avoid
detection in the thermocline, but not by a laser beam.
New spy satellite 'Project Guanlan' could use lasers to spot submarines up to 1,600ft (500m) below the ocean's surface.
These
lasers will be so powerful they will make the upper layer of the sea
'more or less transparent', according to scientists involved in the
project.
Researchers claim these artificial laser beams could be one billion times brighter than the sun.
However,
some experts say this type of deep-sea surveillance is 'mission
impossible' as lasers are fundamentally unable to penetrate that deep.
China's new Project Guanlan
satellite uses lasers to spot objects deep under water. In theory when a
laser hits an object - such as a submarine - pulses bounce back and are
picked up by sensors, which can determine the size, shape and location
of the object
Project Guanlan, meaning “watching the big waves”, was officially
launched in May at the Pilot National Laboratory for Marine Science and
Technology in Qingdao, Shandong.
Its components are being developed by more than 20 universities across the country.
For
more than half a century naval researchers have been attempting to
create a laser using Lidar (a portmanteau of 'light and radar.').
In
theory when a laser hits an object - such as a submarine - pulses will
bounce back and be picked up by sensors, which will be able to determine
its shape.
Scientists are working on a device they hope will be able to reveal the
location of a target as far as 500 metres below the ocean surface.
Experiments carried out by the United States and
former Soviet Union achieved maximum detection depths of less than 100
metres, according to openly available information.
That range has been extended in recent years by
the US in research funded by Nasa and the Defence Advanced Research
Projects Agency (DARPA). A device developed by DARPA, for example, was
mounted on a spy plane and achieved reliable results at a depth of 200
metres, detecting targets as small as sea mines.
According to researchers, this high-powered laser beam is so powerful it would be
able to scan an area as wide as 62 miles (100km) on land, or concentrate on
one spot just 1km wide.
It will be used in conjunction with a microwave radar, also mounted on the satellite, to better identify targets.
Although the radar cannot penetrate water, it
can measure the surface movement with extremely high accuracy – so when a
moving submarine creates small disturbances on the surface, for
example, the radar will tell the satellite where to throw the laser
beam.
Lidar uses ultraviolet, visible, or near infrared light to image objects.
It
can be used with a wide range of targets, including non-metallic
objects, rocks, rain, chemical compounds, aerosols, clouds and even
single molecules.
China's new spy satellite 'Project
Guanlan' could use lasers to spot submarines up to 1,600ft (500m) below
the ocean's surface. This high-powered laser beam will be so powerful it
would be able to scan an area as wide as 62 miles (100km) on land
(stock image)
However, it is negatively affected by fog, murky water and marine life.
It also works less well in water as light scatters when it hits the surface.
Researchers say the aim of the project is to strengthen Chinese surveillance.
Song Xiaoquan, who is involved in the project, said it will make the upper layers of the ocean 'more or less transparent'.
He said it 'will change almost everything'.
Dr Xuaiquan said he did not know when the satellite would be ready.
“Five hundred metres is ‘mission impossible’,” said a lidar scientist
with the Shanghai Institute of Optics and Fine Mechanics at the Chinese
Academy of Sciences, who is not involved in the project.
'They
[project researchers] won't be able to break through the darkness
guarded by Mother Nature – unless of course they are Tom Cruise, armed
with some secret weapons,' one anonymous researcher from the Shanghai
Institute of Optics and Fine Mechanics at the Chinese Academy of
Sciences told SCMP.
WHAT IS LIDAR TECHNOLOGY AND HOW DOES IT WORK?
Lidar
is a remote sensing technology that measures distance by shooting a
laser at a target and analysing the light that is reflected back.
The technology was developed in the early 1960s and uses laser imaging with radar technology that can calculate distances.
It was first used in meteorology to measure clouds by the National Center for Atmospheric Research.
The term lidar is a portmanteau of 'light and 'radar.'
Lidar
uses ultraviolet, visible, or near infrared light to image objects and
can be used with a wide range of targets, including non-metallic
objects, rocks, rain, chemical compounds, aerosols, clouds and even
single molecules.
A narrow laser beam can be used to map physical features with very high resolution.
This
new technique allowed researchers to map outlines of what they describe
as dozens of newly discovered Maya cities hidden under thick jungle
foliage centuries after they were abandoned by their original
inhabitants.
Aircraft with a LiDAR
scanner produced three-dimensional maps of the surface by using light in
the form of pulsed laser linked to a GPS system.
The technology helped researchers discover sites much faster than using traditional archaeological methods.