from the world's big
Researchers devise an effective new predictive tool for maritime first-responders.
- Predicting the locations of objects and people lost at sea is devilishly difficult.
- MIT and other institutions have developed a new algorithm that identifies floating "traps" that can attract floating craft and people.
- The new TRAPS system has just completed a successful first round of testing.
When the first pieces of Malaysian Air Flight 370 finally turned up in July 2015, they were found on Réunion Island off the eastern coast of Africa in the Indian Ocean, thousands of miles from the best-guess location of where the plane went down. Experts weren't especially surprised at the drift, given the complexities of the ocean.
Finding a missing craft or person at sea in a hurry is a nightmare for first responders, and the math involved in tracking survivors — and debris — is anything but simple, given the sea's ever-changing mix of wind, weather, and wave conditions.
Researchers at MIT, the Swiss Federal Institute of Technology (ETH), the Woods Hole Oceanographic Institution (WHOI), and Virginia Tech recently announced the first successful trials of their new "TRAPS" system, a system they hope will provide faster, more accurate insights into the floating locations of missing objects and people by identifying the watery "traps" into which they're likely to be attracted. The team's TRAPS research is published in the journal Nature Communications.
According to Thomas Peacock, professor of mechanical engineering at MIT, "This new tool we've provided can be run on various models to see where these traps are predicted to be, and thus the most likely locations for a stranded vessel or missing person." He adds that, "This method uses data in a way that it hasn't been used before, so it provides first responders with a new perspective."
A Eulerian approach
Image source: MIT
The TRAPS acronym stands for "TRansient Attracting Profiles." It's an algorithm based on a Eulerian mathematical system developed by lead study author Mattia Serra and corresponding author George Haller of ETH Zurich. It's designed to discover hidden attracting fluidic structures in an onrush of changing data.
The traps the researchers seek are regions of water that temporarily converge and pull in objects or people. "The key thing is," says Peacock, "the traps may not have any signature in the ocean current field. If you do this processing for the traps, they might pop up in very different places from where you're seeing the ocean current projecting where you might go. So you have to do this other level of processing to pull out these structures. They're not immediately visible."
The new algorithm crunches through data representing the most reliable available wave-velocity snapshots at the last-known position of the missing item, and rapidly computes the location nearby traps in which a search is likely to be productive. As velocity data is continually updated, so is TRAPS.
Comparing the new Eulerian algorithm with previous Langrangrian predictive methods, Serra says, "We can think of these 'traps' as moving magnets, attracting a set of coins thrown on a table. The Lagrangian trajectories of coins are very uncertain, yet the strongest Eulerian magnets predict the coin positions over short times."
Image source: MIT
Theory is one thing, and functioning out on the real, maddeningly complex ocean is another. "As with any new theoretical technique, it is important to test how well it works in the real ocean," says Wood Hole's Irina Rypina.
The study authors were pleased — and surprised — at how well TRAPS worked. Haller says, "We were a bit skeptical whether a mathematical theory like this would work out on a ship, in real time. We were all pleasantly surprised to see how well it repeatedly did."
The researchers tested TRAPS off Martha's vineyard in the Atlantic Ocean in 2017 and 2018. WHOI sea-going experts assisted as they attempted to track the trajectories of a range of floating objects — buoys and mannequins among them — set into the water at various locations.
One challenge is that different objects may behave in their own ways in the ocean. "These objects tend to travel differently relative to the ocean because different shapes feel the wind and currents differently," according to Peacock.
"Even so," says Peacock, "the traps are so strongly attracting and robust to uncertainties that they should overcome these differences and pull everything onto them."
In their experiments, the researchers tracked freely floating objects for hours via GPS as a way to verify the TRAPS system's predictions. "With the GPS trackers, we could see where everything was going, in real-time," says Peacock. Watching the objects move via GPS, the researchers, "saw that, in the end, they converged on these [predicted] traps."
The researchers now have sufficient faith in TRAPS that they plan on sharing it soon with the U.S. Coast Guard. Says Peacock:
"People like Coast Guard are constantly running simulations and models of what the ocean currents are doing at any particular time and they're updating them with the best data that inform that model. Using this method, they can have knowledge right now of where the traps currently are, with the data they have available. So if there's an accident in the last hour, they can immediately look and see where the sea traps are. That's important for when there's a limited time window in which they have to respond, in hopes of a successful outcome."
If you were awaiting screaming death from the skies, you can relax. For now.
- China's Long March 5 rocket core has landed safely in the Atlantic Ocean following an uncontrolled entry.
- Most of the time, returning hardware that doesn't burn up plunges into the ocean or uninhabited areas.
- There have been two larger returnees in the past, though this one was quite big.
Maybe future generations will look back on these early days of space exploration and chuckle at what we had to suffer through. We live in a time when, every now and then, word goes out that some giant chunk of uncontrolled defunct space junk is about to crash down upon us somewhere, so, um, duck? The hope during such moments is that the deadly debris will land in the ocean that covers most of the Earth's surface or in some unpopulated area, and it usually does. Usually.
Anyhow, if you've been anxiously looking up this week — either at the sky or your ceiling in quarantine — waiting for the core section of China's Long March 5 (CZ-5B) rocket to end you, you can breathe a sigh of relief. It landed safely, for humans anyway, in the ocean off the west coast of Mauritania in northwest Africa on May 11.
Long March into the sea
The CZ-5B-Y1 core stage is in a 155 x 366 km orbit, and is expected to reenter around May 11. At 17.8 tonnes, it is the most massive object to make an uncontrolled reentry since the 39-tonne Salyut-7 in 1991, unless you count OV-102 Columbia in 2003.— Jonathan McDowell (@planet4589) May 7, 2020
Though CZ-5B is one of the largest craft to come down in an uncontrolled reentry, its size is not the only thing that had astronomers like Jonathan McDowell, of the Harvard-Smithsonian Center for Astrophysics, on the edge of their seats. "I've never seen a major reentry pass directly over so many major conurbations!" he tweeted. (A conurbation is an extended urban area.)
While some debris comes down via a controlled landing, that was not the plan for CZ-5B. McDowell tells CNN, "For a large object like this, dense pieces like parts of the rocket engines could survive reentry and crash to Earth." No biggie, he says, since, "Once they reach the lower atmosphere they are traveling relatively slowly, so worst case is they could take out a house."
CZ-5B took off just a week or so ago, on May 5 for just a few days in orbit. Some of its 30-meter-long core stage burned up on reentry, and apparently none of what remained hit anyone, but there are reports of property damage in the Côte d'Ivoire village of N'guinou.
We’ve ducked debris before
A no-doubt radioactive piece of Cosmos 954
Image source: Natural Resources Canada/Wikimedia
At this point, there have been a number of well-publicized spacecraft plummeting down destination-unknown. Probably the scariest was the return of the 4.4-ton Soviet-era spy satellite Cosmos 954. What made its uncontrolled re-entry so frightening is that it was nuclear-powered and threatened to spew radioactive material all over wherever or whomever. The original plan had been to boost it high into a nuclear-safe orbit, but a separation failure doomed the craft to fall back to Earth.
In the end, Cosmos 954 did crash in Northwestern Canada, blowing radioactive debris over a wide area. Canada billed the U.S.S.R $6 million for the cleanup, of which only $3 million was eventually paid.
Probably the first widely publicized uncontrolled return, and one of the two most massive, was of Skylab in 1979. It was another case of a craft coming back earlier than intended, and though NASA couldn't control the 77-ton craft's reentry point, it could control the manner in which it tumbled on down. The nail-biting ended on July 11, 1979, when most of Skylab burned up over the Indian Ocean, though some big pieces survived the descent and landed southeast of Perth, Australia. No one got hurt. The Australian town of Esperance charged NASA $400 for littering. The U.S. also didn't pay up.
Another piece of debris larger than CZ-5B was the Soviet Salyut 7 after nine years in orbit. At the time it came down, it was docked with another spaceship, Cosmos 1686. Salyut 7 weighted in at about 22 tons, as did Cosmos 1686. The connected pair of craft reentered together, burning up and breaking apart over Argentina, with bits raining down on the town of Capitan Bermudez. Amazingly, no one was injured.
One could say we've been pretty lucky so far, though it's hard not to look forward to a time when dying spacecraft can be somehow vaporized out in space where it's safe instead putting those of us down here at absolutely-nothing-you-can-do-about-it risk.
'Operation Invisibility Cloak' was a waste: Hamburg would soon be firebombed to bits
- In 1941, the Nazis camouflaged an entire lake at the centre of Hamburg.
- A painted tarp was made to look like a bunch of city blocks from above, in the hope of misdirecting RAF bombers.
- But the Brits weren't fooled, and Hamburg would later suffer horrific firebombing.
Operation Invisibility Cloak<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjg2OTI3My9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0ODExNTUwOH0.GHMQb3Lae8r2HnqtfxuCPAnnBtW7fu45baB3FdnerBo/img.jpg?width=980" id="c29b1" class="rm-shortcode" data-rm-shortcode-id="31f3b8dafa11442479ee067d501796b4" data-rm-shortcode-name="rebelmouse-image" alt="\u200bBefore and after: the Binnenalster and Hamburg's central train station." />
Before and after: the Binnenalster and Hamburg's central train station.
Image: Reddit<p>Now you see it, now you don't: these images, taken by the Royal Air Force in 1941, show how the same part of Hamburg suddenly looked very different from above. </p><ul><li>The most notable difference is the disappearance of the <em>Binnenalster</em>, one of two artificial lakes that mark the center of Hamburg. It has been covered to look like regular city blocks from above. </li><li>Hamburg's <em>Hauptbahnhof</em>, the city's central train station, clearly visible on the top image, has also been camouflaged (although perhaps less effectively). </li><li>A fake bridge, made from wood, wire and thatch, has been slung across the lower part of the <em>Außenalster</em> - the other, larger lake in central Hamburg. By re-creating the actual, hidden <em>Lombardsbrücke</em>, the camouflage operation creates a fake Binnenalster, just north of the real one. </li></ul>This large-scale deception was meant to deceive Allied bombers into dropping their payload on strategically less important parts of the city. The Nazis called it <em>Operation Tarnkappe</em> ('Operation Invisibility Cloak'), but that name was far too optimistic.
Many attempts at deception<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjg2OTMxMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYwMjA2Mjc1MX0.-UClFxXeErMZY3YqtjD47Kd2K2GPfqpgKy6p9_KMsJ8/img.jpg?width=980" id="fe7bb" class="rm-shortcode" data-rm-shortcode-id="7970830b010cbe5338add2bd7ce3b0c9" data-rm-shortcode-name="rebelmouse-image" alt="An Avro Lancaster of No. 1 Group, Bomber Command, silhouetted against flares, smoke and explosions during the attack on Hamburg, Germany, by aircraft of Nos. 1, 5 and 8 Groups on the night of 30/31 January 1943. This raid was the first occasion on which H2S centimetric radar was used by the Pathfinder aircraft to navigate the force to the target. The pilot of the photographing aircraft (Lancaster 'ZN-Y' of No. 106 Squadron, based at Syerston) was Flt Lt D J Shannon who, as a member of No. 617 Squadron, took part in Operation CHASTISE (the "Dams Raid") during the following May." />
RAF Lancaster bomber over Hamburg during an attack on the night of 30-31 January, 1943.
Image: Imperial War Museum – public domain.<p>Firstly, because the British bombers targeting Hamburg didn't orient themselves on the Alster lakes. They were guided in by the Elbe, Hamburg's major river. </p><p>But most of all, because the Brits caught on quickly to the deception. In fact, the London papers reported on the operation soon after its completion. On July 1941, several published these 'before' and 'after' images.</p><p>Operation Tarnkappe was but one of many attempts to deflect the attention of Allied bombers from valuable targets on the ground. Just around Hamburg, the Nazis faked 80 air strips and 32 industrial and traffic installations, while they attempted to cloak real factories, military installations and even Hamburg City Hall. </p><p>When the Alster froze in the cold winter of 1940/41, the Nazis planted hundreds of pine trees on the Alster, hoping to trick Allied pilots into thinking they were flying over a forest, instead of the centre of Hamburg. <br></p><p>None of that really made a difference.</p>
Coming within range<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjg2OTMyNC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0MDg3NjI1NH0.vUBep-nMhhd6H3rQi0oj6Vtp0jCC_RAEZLZLyu3t5kg/img.jpg?width=980" id="89fbc" class="rm-shortcode" data-rm-shortcode-id="c1e1305882216fa67f92f375a97b88a4" data-rm-shortcode-name="rebelmouse-image" alt="\u200bAs the range of Allied fighter craft expanded, bombing raids deep into Germany became relatively safer for the air crews." />
As the range of Allied fighter craft expanded, bombing raids deep into Germany became relatively safer for the air crews.
Image: Reddit<p>As a major industrial center, home to shipyards and harbor for U-boats, the port city of Hamburg was an important target for Allied bombing raids throughout the war. </p><p><span></span>As British and American airplane technology advanced, Hamburg came within easier range of the Allied bombing effort.</p><p>After concentrating on the industrial Ruhrgebiet in western Germany, closer to the UK, Allied Bomber Command eventually started paying its deadly visits to Hamburg. </p><p><span></span>In July 1943, the Allies unleashed Operation Gomorrah, history's heaviest aerial bombardment yet. It created a huge firestorm that killed more than 42,000 civilians and completely destroyed 21 km2 (8 sq. mi) of the city. </p>
Payback for Coventry<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjg2OTM0Mi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxOTUwODcwN30.MCyfuCXHOqSY5x_jVPi4tkMLvwQYm2wpu8Y8w-h2EBY/img.jpg?width=980" id="d1be2" class="rm-shortcode" data-rm-shortcode-id="1798f6faae5d3a4cec903710760638b3" data-rm-shortcode-name="rebelmouse-image" alt="Royal Air Force Bomber Command, 1942-1945. Oblique aerial view of ruined residential and commercial buildings south of the Eilbektal Park (seen at upper right) in the Eilbek district of Hamburg, Germany. These were among the 16,000 multi-storeyed apartment buildings destroyed by the firestorm which developed during the raid by Bomber Command on the night of 27/28 July 1943 (Operation GOMORRAH). The road running diagonally from upper left to lower right is Eilbeker Weg, crossed by R\u00fcckertstra\u00dfe." />
The district of Eilbek, totally wiped out by the firestorm caused by Operation Gomorrah.
Image: Imperial War Museum – public domain.<p>During the worst night of the attacks, asphalted streets burst into flame, the fiery tornados swept people up into the sky, and many more died of asphyxiation in bomb shelters as the fires consumed all the oxygen in the city above. </p><p>A million people fled the city, which saw its production capacity severely handicapped for the rest of the war. After the war, the level of destruction was compared to that of Hiroshima. </p><p>Destroying further German cities by firestorm was subsequently called 'hamburgisation' by the Allies; a reply in kind to Joseph Goebbels' cynical invention of the verb 'coventrisieren' to describe the wholesale destruction of a city by aerial bombardment (in reference to the German air raid on Coventry of 14 November 1940). <br></p>
Hamburg, uncloaked<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjg2OTM2NC9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY0ODgwNDE0NX0.8Uy6eYDaj0QuducfJou0xs6-yZym41aqkP0U5Ab7eyo/img.png?width=980" id="aae13" class="rm-shortcode" data-rm-shortcode-id="bd060a159ad89893221dfd850517ac6f" data-rm-shortcode-name="rebelmouse-image" alt="Central Hamburg today, with the Au\u00dfenalster and Binnenalster - and even the train station - clearly visible." />
Central Hamburg today, with the Außenalster and Binnenalster - and even the train station - clearly visible.
Image: Google Earth
The racing plane is hoped to be the fastest electric plane in existence.
- The electric aircraft industry is just starting to get off the ground, with Siemens breaking the world record for the fastest electric aircraft in 2017.
- With ACCEL (Accelerating the Electrification of Flight), Rolls-Royce intends to beat that record in the spring of 2020.
- While these are existing developments, the field of electric aviation has significant challenges to face before we can expect to see electric long-distance passenger planes.
The age of electric flight<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjIxMjE1My9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxNTI0NjQ1NH0.hUbX0LdIKwaKDVJqN7jUsBNe1wr1YfQ_vvnJq-vibPE/img.jpg?width=980" id="10a22" class="rm-shortcode" data-rm-shortcode-id="41f59059c97fbd80be5bb3c09c353f82" data-rm-shortcode-name="rebelmouse-image" alt="ACCEL" />
Our biggest stumbling block? Batteries.<p>While reducing emissions is a nice bonus for these companies, much of this development is driven by simple economics; electricity is far, far cheaper than conventional fuel, and even after investing in all this R&D, air travel will be significantly more cost-effective.</p><p>That R&D has delivered results. Much of the technologies involved in electric aircraft and electric vehicles in general has advanced extremely rapidly, with one crucial exception: batteries.</p><p>Without a means of storing large amounts of energy more densely and more efficiently, electric aircraft's range will be significantly limited. Currently, <a href="https://www.atag.org/facts-figures.html" target="_blank">80 percent</a> of aviation CO2 emissions result from flights that travel over 1,500 km (a little less than 1,000 miles), distances that no electric aircraft is capable of covering.</p><p>Batteries can be optimized for <a href="https://qz.com/1588236/how-we-get-to-the-next-big-battery-breakthrough/" target="_blank">six different characteristics</a>: their energy density, cost, lifespan, temperature endurance, safety, and power (or the rate at which energy can be released). A smartphone's lithium-ion battery, for instance, should be cheap and endure swings in temperature, but it doesn't need to last too long or release too much energy at once. An airplane's battery system needs to excel on all six of these metrics.</p><p>Batteries are tricky, but <a href="https://newatlas.com/science/battery-breakthroughs-2019/" target="_blank">advances are being made</a> in this industry. With further advancements in electric aviation technology and battery technology, we might get to continue to visit the beautiful places that Earth has to offer without risking their disappearance in the process.</p>
Following two deadly crashes, the FAA has been engaged in a lengthy review process of the Boeing 737. With recent news that the review may continue into 2020, Boeing has opted to halt production of the plane.
- Boeing has decided to halt the production of the 737 Max after the FAA announced that its review of the plane will extend into 2020.
- After two recent and deadly crashes, the FAA has grounded all 737-model planes.
- The news spells financial trouble for Boeing, especially since another one of its major planes — the 787 Dreamliner — has been receiving significant quality complaints.
Bad news for Boeing<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjE2OTU3Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNDM2OTExMH0.x-wJElpcFafqPTGqDju4B0kxAyKpC1Wxj_GTfAOu2L0/img.jpg?width=1245&coordinates=411%2C506%2C168%2C444&height=700" id="37194" class="rm-shortcode" data-rm-shortcode-id="dba808e64269c8741c0beada88f34705" data-rm-shortcode-name="rebelmouse-image" />
Yin Liqin/China News Service/Visual China Group via Getty Images<p>Altogether, this doesn't paint a rosy future for Boeing. Without being able to deliver its planes, Boeing has not yet made any revenue from them. Additionally, the airline company will be on the hook for billions of dollars to its airline customers as compensation for the cost of the grounding, it's been involved in various lawsuits whose associated costs have not been disclosed to shareholders, and it's promised to set aside a <a href="https://www.cnn.com/2019/07/18/business/boeing-737-max-second-quarter-charge/index.html" target="_blank">$100 million fund</a> to help the families of the crash victims.</p><p>On top of this, numerous concerns have been raised about the quality of one of Boeing's other major airliners, the 787 Dreamliner. Airlines have made several private complaints to Boeing about the 787's quality control procedures as being "<a href="https://www.businessinsider.com/boeing-787-dreamliner-airline-complaints-quality-production-2019-8" target="_blank">way below acceptable standards</a>."</p><p>A former quality control manager at the plant in Charleston, South Carolina, where the 787 is manufactured <a href="https://bigthink.com/politics-current-affairs/boeing-safety-issues" target="_self">claimed</a> that management "just wanted to get the planes pushed out the door and make the cash register ring." In an interview, he cited non-working oxygen masks, metal slivers rattling about the compartment where the plane's avionics ran, and a pervasive culture of speed over quality at his plant.</p>