Monday, May 3, 2021

Thousands of barrels of suspected toxic DDT found dumped in California ocean

Barrels and targets of interest were found in nearly all areas of the 36,000 acres surveyed and extended beyond dumpsite limits, which is roughly 12 miles offshore Los Angeles, and eight miles from Catalina Island. Credit: Scripps Institution of Oceanography at UC San Diego.
 
A heat map showing concentrations of targets detected in the San Pedro Basin.
There are several distinct track-line patterns in the surveyed area, suggesting that the dumping was repeatedly done from an underway platform such as a moving ship or barge.
Credit: Scripps Institution of Oceanography at UC San Diego. 
 
From The Guardian by AP
 
Extent of possible toxic waste site near Catalina Island ‘staggering’, says chief scientist on sea survey
 
 
In this 2011 image provided by the University of California Santa Barbara, a barrel sits on the seafloor near the coast of Catalina Island.
Photograph: David Valentine/AP
 
Marine scientists say they have found what they believe to be as many as 25,000 barrels possibly containing DDT dumped off the southern California coast near Catalina Island, where a massive underwater toxic waste site dating back to the second world war has long been suspected.

The 27,345 “barrel-like’” images were captured by researchers at the University of California San Diego’s Scripps Institution of Oceanography.
They mapped more than 36,000 acres of seafloor between Santa Catalina Island and the Los Angeles coast in a region previously found to contain high levels of the toxic chemical in sediments and in the ecosystem.

Historical shipping logs show that industrial companies in southern California used the basin as a dumping ground until 1972, when the Marine Protection, Research and Sanctuaries Act, also known as the Ocean Dumping Act, was enacted.

Resting deep in the ocean, the exact location and extent of the dumping was not known until now.

The territory covered was “staggering”, said Eric Terrill, chief scientist of the expedition and director of the Marine Physical Laboratory at Scripps Institution of Oceanography.

Underwater drones using sonar technology captured high-resolution images of barrels resting 900 metres (3,000ft) below the surface all along the steep seafloor that was surveyed.
They also were seen beyond the dumpsite limits.

“It really was a surprise to everybody who’s worked with the data and who sailed at sea,” he told reporters on Monday.

The survey provides “a wide-area map” of the barrels, though it would be up to others to confirm through sediment sampling that the containers held DDT, Terrill said.
It is estimated between 320 and 640 tonnes of DDT were dumped in the area, 12 miles from Los Angeles, and 8 miles from Catalina Island.

The long-term impact on marine life and humans was still unknown, said Scripps chemical oceanographer and professor of geosciences Lihini Aluwihare, who in 2015 co-authored a study that found high amounts of DDT and other man-made chemicals in the blubber of bottlenose dolphins that died of natural causes.

“These results also raise questions about the continued exposure and potential impacts on marine mammal health, especially in light of how DDT has been shown to have multi-generational impacts in humans,” said Aluwihare, who was not part of the survey expedition.

Diana Aga, a chemistry professor at University at Buffalo who is not affiliated with the study, said the findings were shocking if the barrels were proven to contain the toxic chemical. 
“That’s a lot of DDT at the bottom of the ocean,” she said.

If the barrels had not leaked, they could be moved to a place where disposal was safer, Aga said.
If they leaked, scientists could take samples from the water, sediment and other marine life to gauge the damage.
 
Researchers on the research vessel Sally Ride deploy an autonomous underwater vehicle near Santa Catalina Island. Photograph: AP
 
Scientists conducted the survey from 10-24 March following a Los Angeles Times report last year about evidence that DDT was dumped into the ocean.
Terrill said: “Unfortunately, the basin offshore Los Angeles had been a dumping ground for industrial waste for several decades, beginning in the 1930s. We found an extensive debris field in the wide area survey.”

Scientists started the search where University of California Santa Barbara professor David Valentine had discovered concentrated accumulations of DDT in the sediments and spotted 60 barrels about a decade ago.

High levels of DDT have been detected in the area’s marine mammals, and the chemical has been linked to cancer in sea lions.

Scripps researchers say they hope their survey will support clean-up efforts.
The expedition on the Sally Ride research vessel included a team of 31 scientists, engineers, and crew conducting 24-hour operations and two autonomous underwater vehicles.

Links :

Sunday, May 2, 2021

Image of the week : Isles of Scilly LIDAR picture

courtesy of @HughGraham (LIDAR DEM 1m)
 
visualization with the GeoGarage platform and Google Maps imagery (SHOM nautical raster chart)
 

Saturday, May 1, 2021

Ocean currents, visualized by hundreds of GPS-tracked buoys

 

 
 Animated map shows the movements of hundreds of GPS-tracked buoys.
This gives us an idea of how ocean currents work.
Source: The National Oceanic & Atmospheric Administration's Global Drifter Program Global Drifter Program. 
Only buoys released within 5° latitude and longitude of a coast were included in the visual.

 

Friday, April 30, 2021

The Arctic silk road: Belt and road in North dimension. Fight for the North



From ModernDiplomacy by Maria Smotrytska
 
Today the Arctic is one of the world’s key regions both economically and in terms of military security.
The melting of glaciers opens up not only previously inaccessible territories, but also prospects for global economic and geopolitical rivalry in the Northern hemisphere with the main players of North Europe (Norway, Finland, Denmark), Russia, the United States, and China.
Article emphasized that the development of the Arctic opens up new trade routes, new zones of influence and billions of dollars in profits.
It is the warming of the planet that is largely responsible for this change in thinking, and with polar ice diminishing at a record rate, greater arctic activity could be upon us very soon.
But as there are multiple national claims on polar territory, there are also numerous legal issues to be worked out.
The author underlines that the favorable geographical significance and resource potential of the region make the Arctic one of the key maritime links of the Chinese Belt and Road initiative, as well as titbit for Russia’s ambitious on building Arctic infrastructure and important part of world’s North transshipment waterways.


The Arctic represents much more than a new transportation frontier, however; it is also rich with hydrocarbons and a variety of mineable ores.
It is therefore no surprise that at least five northern nations are laying claim to the area.
The author examines the economic issues that motivate much of this new interest in the most remote northern region on earth.
Main opportunities and challenges in inter-states cooperation in the region are analyzed.

Arctic Territorial Claims
 
Today the Arctic is a theatre of four major areas with contradicting and overlapping claims.
Each of the disputed areas is holding large resource deposits (be it marine biota, hydrocarbons, other minerals and precious metals, on land or offshore seabed) and has also extensive geopolitical meaning to the parties (including control of possible transport routes).
Generally, the Arctic Five (Russia, USA, Canada, Sweden, Norway) have preliminarily agreed on the demarcation lines, by establishing more than half of potential EEZ.
However, the remaining area, including the geographic North Pole, is still under dispute and no agreement has been reached so far.
Besides the considerable territorial gain, having the Pole within its national borders holds an intangible value for its prestige.

Analysing Chinese position towards “Arctic issue”, it is important to remember, that China currently does not have access to the Arctic ocean.
Thus, with no physical access to the Arctic, Chinese strategists have long been concerned about the country’s chances of becoming an Arctic power.
Despite this, in June 2017, the state Committee for development and reform and the State Oceanographic administration of China named the Arctic as one of the directions of the “One belt, One road” project.
The “Concept of cooperation at sea within the framework of the BRI” refers to the need to involve Chinese companies in the commercial use of Arctic transport routes.

Soon after Russia has signed a Memorandum of Understanding with the Chinese Oceanographic authority, aimed at expanding international cooperation in the field of Arctic and Antarctic researches.
The same documents were signed with China by Norway, the United States, Germany, Chile and Argentina.

There are three potential routes across the Arctic: the Northeast passage around Eurasia, the Northwest passage around North America and the Central Arctic ocean route.
For China, they offer a shorter and cheaper alternative to current shipping routes, which reach major markets in Europe via the Indian ocean and the Suez canal.

In practice, Yong Sheng, owned by COSCO Shipping, was the firstChinese cargo ship to master the Northern sea route (Northeast passage) in 2013.
After a trial voyage, the Chinese carrier COSCO showed interest in further using this project.
However, analysts expressed doubts about its profitability.
The main problems were that when traveling along the Northern sea route, ships of lower cargo capacity have to be used, the route is seasonal, and the travel conditions are extreme.

In the summer of 2017, another six Chinese vessels took this route.
In September, the Chinese research vessel Xue Long made its first Northwest passage voyage along the Northern coast of Canada, reducing the travel time from New – York to Shanghai by seven days compared to the route through the Panama canal.

It should be borne in mind that China’s position is quite convenient in geopolitical terms : it is one of the observer States of the Arctic Council.
In total, there are eight countries in the region (Canada, the United States, Denmark, which has access to the Arctic via Greenland, Norway, Russia, Iceland, Sweden and Finland) and 13 other countries that do not have access to the Arctic, but whose using the function of monitoring the relations of the countries in the region.
Thus, China is actively using its status with the development of the Arctic programme.

It should be empathized that Beijing’s position on the development of the Arctic route supports the view that both routes contain potentially very profitable transit points that can shorten the path between Asia and Europe, not to mention between Asia and parts of North America.

In January 2018, the state Council of China published the first “White paper on China’s Arctic policy”, which states that Beijing is interested party in Arctic Affairs.
It wasnoted that China intends to create,jointly with other States, the sea trade routes in the Arctic region within the framework of the “Polar Silk Road initiative”.
Thus, it was decided that the Polar Silk Road will be part of the broader Chinese “Belt and Road” program, creating sea trade routes and strengthening trade relations with different countries in the region.

Due to the fact that other Trans – Eurasian sea transportations may be extremely unstable in the long term, especially in terms of security, the Chinese authorities have shown interest in the Northern, alternative sea route.

Analyzing the logistics of the existing route through the Suez canal and the Mediterranean sea, even taking into account the planned expansion, it is easy to see that it is already overloaded.
Secondly, the middle East is still a zone of instability and its infrastructure requires large financial investments.

Another potential route, through Central America – the Panama or Nicaraguan canal – is also not entirely rational in terms of reconstruction and big amount of investments.
It makes sense to use it for Asian – American trade, which is also planned to be improved in terms of logistics and infrastructure.

Based on this, it can be noted that the two remaining Polar routes have begun to arouse real strategic and long-term interest on the Chinese side.

The first of these routes is the American Northwest corridor (Northwest passage), first passed by water by Roald Amundsenat the beginning of the last century, but it also retains certain problems.
First of all – with Canada, which believes that the Northwest Passage passes through its territorial (internal) waters.
The second problem is the US position: the country’s authorities do not want to have a trade highway under the control of such strategic competitor as China.

The second alternative is the Northern sea route, which runs North of the Russian Federation.
Due to China’s increasing interest in developing the logistics of the Northern route, the Russian government has set a high bar for a large-scale Arctic project running along the coast of the new sea route, which is becoming more accessible to navigation as a result of climate warming and ice melting.
The head of state outlined a large-scale task: to reach the level of 80 million tons per year by 2025.

In addition to the development of the construction of a new port in Russia’s Arkhangelsk (the capital of the region on the White sea is one of cities in the Far North), construction of a new port and a railway line has begun, which should connect with one of the branches of the Chinese BRI.

Thus, it can be noted that today the Arctic opens up new prospects for trade between Europe and Asia.
The North, which has huge reserves of hydrocarbons, is of interest not only to Western countries, but also to China.
The use of sea routes and natural resources in the Arctic can have a huge impact on the energy strategy and economic development of China, which is one of the world’s leaders in foreign trade and is the largest consumer of energy in the world.
For example, the Northern sea route will allow China to deliver cargo to Europe by sea faster than the 48 days (that it takes on average) to travel from the Northern ports of China to Rotterdam via the Suez canal.
Last year, the Russian Arctic gas tanker “Christophe de Margerie” reached South Koreafrom Norway without an icebreaker escort, and the journey took only 15 days.

Thus, the Northern sea route will allow China to deliver cargo to Europe faster by sea, reduce the route by 20 – 30%, and save on fuel and human resources.
Given that 90% of Chinese goods are delivered by sea, the development of the Arctic silk road promises Beijing serious savings and profit growth .

In addition to gaining possible economic advantages, China hopes to increase its energy securitythrough Arctic trade routes.
Currently, most of the fuel imported by the Asian giant crosses the Strait of Malacca, which connects the Indian ocean with the South China sea.

Thus, it can be traced that China is interested in Arctics Arctic natural resources.
This region contains a fifth of the Earth’s natural resources.
However, even if this is the case, China’s interest in Arctic underground storerooms is rather long-term and the calculation is made for the remote future.
The problem is that China is still dependent on foreign technologies for offshore drilling, even in the warm seas surrounding it.
Technologies for extracting natural resources in Arctic waters are much more complex, and China does not have enough sufficient experience in this area.

Also, analysing the logistics of BRI routes, it can be seen why China is getting more interested in developing alternative North corridors :

The transport routes of the “Silk Road Economic Belt” project cross the Eurasian continent in the middle, the route of the “Maritime Silk Road of the XXI century” project runs along the South and there is no Northern water route yet.
The main value of the Arctic sea route is that the regions through which it passes are relatively calm and stable.
It should be noted that the “Economic Belt” crosses many countries with high conflict and crisis potential (Central Asia, Middle East, East Europe).
The “Maritime Silk Road of the XXI century” runs through the South China sea, South – East Asia, and the Indian ocean – the region which has similar problems.
Also in terms of infrastructure development these roads may cause certain risks, connected with big number of participants, different level of infrastructure capacities of countries and different legislative obstacles.
Thus, the Northern route may act as a more stable alternative that it can become a serious incentive that will contribute to the Eurasian economic integration.

The economic component of Arctic direction of the BRI is no less important.
The Chinese expert reminded that the routes through The Northwest passage and the Northern sea route would save Chinese companies time and money on their way to Western countries.
Taking into account the melting of ice in the Arctic ocean, the Northern sea route can become an alternative to the main transcontinental route that runs through the southern seas of Eurasia and further to Africa via Suez canal.
Thus, the passage of a cargo ship from Shanghai to Hamburg along the North sea route is 2.8 thousand miles shorter than the route through Suez canal.

Studying in details Arctic direction of the BRI, the main projects can be considered :
China–Russia Yamal LNG

This project is considered the world’s largest liquefied natural gas (Hereinafter LNG – Auth.) initiative, this is China and Russia’s first joint Arctic Silk Road venture.
Partners in the project include Russia’s Novatek, the China National Petroleum Corporation (CNPC), French firm Total, and China’s Silk Road Fund.
Together, CNPC and the Silk Road Fund hold a 30% stake.

Chinese shipping firms handle LNG cargos bound for China.
In July 2018, seven months after operations started, the first shipment of LNG from Yamal arrived in Jiangsu province’s Nantong.
A second phase of the project is now being constructed on the Gydan peninsula, to the east of Yamal, and due to begin operating in 2023.Current status: Production commenced December 2017.
Payakha oilfield

In June 2019, the China National Chemical Engineering Group and Russian firm Neftegaz holding signed a deal on developing the Payakha oilfield, promising investment of US$5 billion over four years.

This is Russia and China’s second Arctic Silk Road energy project after Yamal.
Payakha lies on the Taymyr peninsula in the region of Krasnoyarsk.
According to reports, the project includes the construction of six crude oil processing facilities, a crude oil port capable of handling 50 million tonnes a year, 410 kilometres of pressurized oil pipelines, a 750-megawatt power station and an oil storage facility.
Current status : Deal signed.
Zarubino port

Located just southwest of Vladivostok and close to the Chinese border, the port of Zarubino is ice free year-round.
In 2014, the government of Jilin province, the China Merchants Group and Russia’s largest port operator signed a framework deal to develop Zarubino into the biggest port in northeast Asia over 18 years, with capacity to handle 60 million tonnes of goods a year.
Railways linking the port with inland regions of China will also be built.

In September 2018, as the first stage of this project, a shipping route started running from Hunchun on the Tumen river in Jilin to Zarubino and then on to Zhoushan in Zhejiang province.
The new Zarubino port will strengthen links between northeast China and the rest of the world, and aid development in Russia’s far east.
It will also be a key link on the northeast passage trade route to Europe.
Current status: Deal signed, progressing.
Arkhangelsk deepwater port

Arkhangelsk is the largest city on Russia’s northern coast, situated on the country’s European side close to Finland.
The new deepwater port has been planned for over a decade.
It will be located 55 kilometres from Arkhangelsk on the island of Mud’yug, which lies in the Dvina river delta close to existing port infrastructure.
Linking up with Russia’s railway network, the port will help develop a combined sea–land transportation system, and improve links to Siberia.

The local government predicts the new port and associated railways will create 40,000 jobs in the region.
According to one expert, the China Poly Group signed an agreement of intent in 2016, earmarking investment of 550 million yuan (US$79 million).
The China Ocean Shipping Company has also made its interest in the project clear.
Current status: Planning.
China–Finland Arctic Monitoring and Research Centre

In April 2018, China’s Institute of Remote Sensing and Digital Earth signed an agreement with Finland’s Arctic Space Centre to establish a new monitoring and research centre for the polar region.
The facility, based in northern Finland’s Sodankylä, will collect, process and share satellite data, providing an open international platform to support climate research, environmental monitoring and Arctic navigation.

The centre will contribute to China’s “Digital Silk Road” plan, which aims to create a spatial information system for regions covered by the BRI.
It will also promote the Chinese Academy of Sciences’ “Global Three Poles Environment” project, which aims to better understand global climate change.
The project was inaugurated in October 2018.
Current status: Deal signed.
China–Iceland Arctic Science Observatory

In October 2018, the China–Iceland Arctic Science Observatory was officially opened in the city of Karholl in northern Iceland.

Set up to monitor climate and environmental change in the Arctic, the observatory is managed by the Polar Research Institute of China and Iceland’s Institute of Research Centres.
It can accommodate 15 people and will also be open to researchers from third countries.

The partnership started in 2012 when the two governments signed a deal on Arctic cooperation.
That year also saw a memorandum of understanding signed between organisations from the two countries on a joint aurora observatory.
Plans were expanded in 2017, with work at the observatory now covering the atmosphere, the oceans, glaciers, geophysics, remote sensing and biology.
Current status: Operating since late 2018.

Thus the modern logistics projects such as “Arctic Silk road” and“Maritime Silk Road of the XXI century” connect China with other countries of South – East Asia, the Middle East, East Africa and some EU countries through sea trade routes, such as such in the Red sea.
Thus, it can seen that three new transport corridors will connect Europe with the Russian Federation, Central Asia, China, India, Pakistan, Iran, Korea, Japan, Vietnam and Thailand.
Analysing“Maritime Silk Road” logistics it becomes clear that the project is designed to connect three continents into a single transport system: Europe, Asia and Africa.
It is no secret that many of these countries have a lot of political differences, but the benefits that the implementation of this large-scale project promises can make them forget about old claims to each other.

One of the long-term prospects for the development of the BRI project is the creation of free trade zones with countries participating in the initiative.
The result of such multi-countries collaboration may be the emergence of a large-scale free trade zone from the North – Western provinces of China, Central Asia, to Europe and Africa.
About three billion people live on the project’s path.
In this case, we are talking about the “mega – market”, and, of course, about the“mega – potential”.

Analysing the development of new Chinese silk road in the north, we should understand, it is worth recalling that the Arctic is one of the few places on the planet that has yet to be “fully registered with residence”.
After all, initially the resources of the Arctic were not clearly divided between countries.
At least five countries now claim the Arctic zones: Russia, Norway, Denmark, Canada and the United States.
All of them have direct access to the coast of the Arctic ocean.
We also need to mention at least two another “Arctic powers”, which don’t have a physic access to Arctic land, but have a lot of influence in the worlds politics : China and India.
National claims may be supported by various arguments in the future, but it is clear that the main one are practical, that is, the country’s real readiness to actively develop the North.

Thus, it can be seen that contradictions between interested countries in the Arctic may well lead to an increase in international tension in general and the likelihood of local international conflicts in particular.
After all, this region is worth to fight for and conflict situations can really arise.

Links :

Thursday, April 29, 2021

The U.S. Navy’s new unhackable GPS alternative: the stars

From PopularMechanics by David Hambling

GPS is a world-changing technology. It’s also incredibly fragile, easily spoofable, and consistently hackable.
That’s why the U.S. Navy and Marine Corps are looking to the stars for a navigational Plan B.

Twenty-five years ago, in 1995, the U.S. Air Force reached a milestone: Its satellite Global Positioning System became fully operational.Today, GPS directs our world, from supertankers to pizza deliveries. But before the creation of this modern navigational marvel, humans looked to the heavens to find their way.

For centuries, using a sextant, a sailor could mark a ship’s location by making a few calculations to determine a star’s position relative to the horizon.
Now a high-tech version of this maritime tradition is finding its way back into practice.

GPS is indispensable these days—but it’s still incredibly fragile.
It can be spoofed with a fake satellite signal, hacked by an adversary, or simply destroyed. Spoofing, hacking, or destroying the stars? Not happening.

GPS may have revolutionized the way we navigate, but for years celestial navigation has been undergoing a quiet revolution of its own.

DON’T CALL IT A COMEBACK
 
The U.S. Navy became less reliant on the traditional sextant back in WWII with the advent of radio navigation tools, but the heavens have remained an important map for sailors and especially pilots. WWII bombers like the B-17 Flying Fortress had an ‘astrodome,’ a transparent hemisphere that allowed the navigator to take star sightings. 

The astrodome, found on the nose of the B-17G in front of the cockpit window, helped navigators find their way using the stars.
SMITHSONIAN INSTITUTIONWIKIMEDIA COMMONS
 
After the war and the birth of the rocket engine, scientists set about giving missiles the same kind of celestial smarts.

The SM-62 Snark cruise missile, developed in the 1950s, featured the first automated celestial navigation system, a mechanical-electrical device that weighed almost a ton.
The Snark’s navigator had a small telescope mounted on three gimbals that rotated to point it to a given area of the sky.
An early photosensor located the stars in the field of view and measured their angles, identifying them from a star catalog.
The makers claimed that the Snark was able to navigate to within about three kilometers, but it never worked that well in practice.

Then again, you don’t need much navigation finesse when you’re delivering a 3.8-megaton nuclear warhead.

How a Sextant Works

Getty Images

It may look daunting, but a sextant simply measures the angle between a heavenly body—star, planet, moon, or sun—and the horizon.

Key components of a sextant are a miniature telescope, a half-silvered mirror (through which the telescope looks), and an index mirror on a moving arm.
Looking at a celestial body through the telescope, you rotate the index mirror until it appears to be on the horizon.
You then note the angle of the arm that corresponds to the angle of the celestial body from the horizon.
Measuring the angle from one heavenly body tells navigators that they are somewhere on a circle on the Earth’s surface, known as the position circle.
For example, at any given moment there are a range of positions from which the sun is at exactly 35 degrees, lying on a circle about 3,000 miles in diameter.
Navigators can plot this circle on the map if they have the relevant charts and know the exact time.
Because the circle is so large, it appears as a straight line on a local map.
Plotting two such circles for two celestial objects gives two lines, and where they intersect is your location—in theory.
Careful navigators usually take three or more sightings, because the lines do not necessarily meet at a single point.
Three lines enclose a triangular area of possible positions traditionally known as a ‘cocked hat.'

Decades later, engineers built modernized celestial navigators, now about the size of a microwave oven, into the B-2 bomber and Trident missile.
An observatory at Boeing’s Guidance Repair Center in Heath, Ohio, checks the location of the North Star every few days, and uses the measurements to calibrate military navigation and guidance systems. In modern missiles, celestial guidance is used in conjunction with an inertial navigation system (INS).

While celestial navigation survived in niche applications like missiles, GPS has edged out the competition because it’s accurate and cheap.
But GPS works only when there’s a good satellite signal, and adversaries are very much aware of that weakness.
 
GPS: REVOLUTIONARY…WHEN IT WORKS
 
In 2018, Russian GPS jamming disrupted a NATO exercise in Scandinavia, and Chinese GPS spoofing signals can cause ships in many coastal areas to see false locations.
Modern military GPS systems feature a range of electronic guards to prevent jamming and spoofing, including directional antennas and a special M-code military satellite signal.

Even with these safeguards, a GPS signal may simply not be there: There are concerns about whether the satellite system might be hacked, or the satellites themselves knocked out by an enemy or a massive solar storm. 
This has focused military minds on alternatives.
 
A soldier checks a map during NATO’s Trident Juncture exercise in October 2018.
Participants accused the Russian government of GPS jamming during the exercise.
LEON NEALGETTY IMAGES 
 
The Navy’s Automated Celestial Navigation System would replace manual shipboard measurements with something more accurate, while Special Operations Command experts are developing a handheld device for commandos.
Both pieces of tech are aiming for GPS-level precision.

“The best accuracy for celestial navigation with certainty is within a couple of meters,” says Benjamin Lane of the Advanced Position, Navigation & Timing Instrumentation unit at Draper Laboratory in Cambridge, Massachusetts.
“In practice, we are within a factor of a few of that.”

SPOOFING, HACKING, OR DESTROYING THE STARS? NOT HAPPENING.
 
The new systems use infrared rather than visible light for locating stars, allowing daytime navigation.
The stars shine just as brightly in the day sky as they do at night, but their light is masked by sunlight scattered by the atmosphere.
The scattering is strongest at short wavelengths.
If you’ve ever glimpsed the sky, you know that blue light is scattered the most.
But glimpse that same sky with a filter that allows only infrared light, and the sky suddenly becomes dark—and filled with stars.

“Twenty years ago, these infrared sensors were quite expensive,” says George Kaplan, a consultant for the U.S. Naval Observatory. 
“Since then, costs have been going down and the pixel count is getting higher.”

The rise of celestial navigation is also helped along with another piece of tech called a “phased optical array,” which does not need to be pointed at a section of the sky like a telescope does.
This type of sensor does not have a lens to focus, but instead has an array of tiny meta-material antennas to capture light.
A processing unit can phase-shift the signal from each antenna to achieve the same effect as a movable, focusing lens.

Lane and his team have already demonstrated a working prototype of such a sensor.
 
A view of SpaceX’s Starlink constellation at night.
YURI SMITYUK / GETTY IMAGES

TWINKLE, TWINKLE, LITTLE SATELLITE

But the biggest development, being pursued by both Draper Laboratories and Trex Enterprises, is an approach that overcomes one of the biggest limits to accuracy.
Traditional celestial navigation requires measuring the angle of a star or planet in the sky.
To do this you need to precisely locate the horizon or, alternatively, the azimuth or true vertical.

That sounds simple, but it isn't.

“Trex has tried infrared detection of the horizon,” says Kaplan. 
“The problem is that the horizon is refractive; it’s very sensitive to temperature differences. You get all sorts of odd reflections, including mirage.”

Others have sensed the azimuth by the polarization of the sky, or by the refraction of starlight, or even angular motion sensors detecting the Earth’s rotation.
None of them comes close to GPS accuracy. But this new approach takes readings from human-made satellites rather than stars, sidestepping the horizon altogether.

A Military History of Celestial Navigation


Longines Weems A-11 Aviators Watch
The precise time is vital for celestial navigation: an uncertainty of 30 seconds means a distance error of ten kilometers.
The Dutch aviator Capt. PVH Weems developed a watch with a second hand that could be set exactly to radio time signal broadcasts, which the U.S. Navy started in 1904, reducing errors
 The U.S. Army Air Corps commissioned its own version of the watch in 1937, the A-11, and issued one to every new aviator.
 
Plexiglas Astrodome
Introduced just in time for WWII bombers, the astrodome was a wonder of materials technology: Plexiglas, a rugged transparent plastic, formed into a dome giving a clear 360-degree view of the night sky. 
The astrodome included a hanging point for a sextant so navigators would not have to hold the weighty instrument.
 
 
Fairchild-Maxson Mark I Line of Position Computer
Calculating position from star readings was a time-consuming and demanding task—there was no ‘app for that’ in pre-electronic days.
The USAAF automated the process with this 1938 mechanical calculating device.
The navigator dialed in the angle readings and the time, and the 20-pound computer did the rest. Several dozen were built and used by the Air Corps and the Navy, but the design proved too expensive.
 
U-2 Driftsight
The dashboard of the U-2 spy plane was dominated by the driftsight, a downward-looking periscope to follow roads and other landmarks for navigation.
When the ground was invisible, flipping a mirror converted the driftsight into a sextant with a view of the sky through a glass bubble on the plane’s nose.
This was helpful in areas like the Arctic with no terrain features and where magnetic compasses were useless.

Nortronics NAS-14V2 Navigation System
Affectionately known as R2-D2, the celestial navigator in the SR-71 Blackbird occupied a position immediately behind the pilot.
Measuring 48 x 46 x 31 in. and weighing 300 pounds, it performed the vital function of keeping the Blackbird on track even at Mach 3, ensuring that the plane’s cameras photographed the right area of interest in the ground.
It also helped keep the valuable plane on the safe side of sensitive international borders.
 
Because satellites are relatively close to the Earth’s surface, observers can calculate their own position based on the angles among different satellites.
The navigator does not need to see the horizon or know the local vertical. Instead, it’s a version of triangulation that any hiker uses when taking angle readings from two mountaintops.

Any visible satellite can be used to navigate if its position is known, and there are now plenty to choose from.
In 2010, fewer than 1,000 satellites were in orbit; that number has more than doubled and is rising fast with mass launches of small satellites. SpaceX’s Starlink constellation alone will add more than 7,000 in the next few years, so there should always be one handy to take a reading.

“Starlink’s satellites are being made less reflective but still trackable,” says Lane. 
“If they are predictable, then we can track and use them.”

The only limit is how accurately a satellite’s position is known.
While the orbital track is usually known exactly, a satellite’s position along the orbital track is affected by atmospheric drag, resulting in a deviation of arc minutes (an error of one nautical mile, or 1,952 meters.)

Fortunately, the North American Aerospace Defense Command (NORAD) tracks many of them with high-precision radar, and can supply the data to military users.

Once these celestial navigation tools are ready for combat, they’ll come in different shapes and sizes.
The B-21 Raider bomber will likely have a more compact, highly precise version of the B-2 Spirit’s R2-D2-like unit that sits behind the pilot.
On Navy ships, the Automated Celestial Navigation System will replace the old brass sextants and provide data that can be fed into shipboard computers along with other navigational sensors. Future ballistic missiles will also include advanced celestial navigation.

And with a new handheld device being developed by Special Operations Command, even the humble foot soldier could be steering by the stars.
 
CELESTIAL LIMITATIONS
 
Senior Chief Petty Officer Jonathan Myers teaches Command Master Chief April Beldo how to use a marine sextant on the USS Carl Vinson.
TRAVIS K. MENDOZA
 
While it is already possible to get a location within 20 meters or so, and devices with more accuracy are in the pipeline, celestial navigation is not quite as handy as GPS.
For one thing, it currently takes much longer to get a reading, often tens of seconds.

For another, Kaplan says that even though infrared imagers work through haze and light cloud cover, they cannot see through dense, low clouds.
Unlike GPS, celestial navigation will not be available 24/7, so it would have to work with an inertial navigation system.
Luckily, these are getting much smaller and cheaper too.

“Another ‘gotcha’ using LEO satellites is that in daytime the light is coming from above,” says Kaplan.
This means the brightest part, the solar array, is pointed away from the Earth and the satellite is much less bright than it is at night.
But the developers are confident that they can overcome these issues, unlocking celestial navigation’s true potential as a GPS substitute—without all the dedicated space hardware, risks of jamming, or vulnerability to cyberattack.

In 1980, the first portable Rockwell GPS receiver was a backpack unit that weighed 20 pounds.
It took five minutes to get a fix and cost around $30,000.
Modern GPS receivers are chip-sized, give an almost instant readout, and cost less than $50.

In 40 years, who knows where the stars might take us.

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