Micro stories - small news bits too small to have their own thread

[Dubious]

what are you trying to do??

Study

Well my study is on European berries I got bored and told my supervisor I wanted Pakistani strawberries to be included and he was like sure if you can get me some we can discuss it...Now I am in search for some ...No one is cooperative to answer my mails...

That is if you do not mind sharing!

I will address you to explore my thread on fragaria ...It kind of explains what I am trying to do

 

[Fenrir]

Scientists Can Turn Human Cells Into Working Lasers

How about this for a bright idea: A team of researchers from Harvard Medical School has developed three different ways to turn individual cells into functioning lasers that emit light when they’re excited.

As New Scientist reports, the team have demonstrated that particles and droplets in skin can be exploited to emit light. In one example, they injected tiny oil droplets, later filled with fluorescent dye, into human cells; when a light pulse hit the droplet, the dye atoms emitted light in a tightly focused beam. In a second example, 10-micron polystyrene beads were ingested by cells known as macrophages — a type of white blood cell — and ultimately served the same purpose as the oil drops.

And in a final example, the team even managed to show that existing fatty droplets inside cells could be used to the same ends. In pig skin — though the same technique should work in human skin — light injected into the skin caused fatty cells tagged with a fluorescent dye to emit laser light in just the same way. “We are all made of lasers,” said Matjaž Humar, one of the researchers, to New Scientist. The results are published in Nature Photonics and Nano Letters.

While the work may seem frivolous, the researchers reckon that the techniques could be used to track and monitor tumor cells, perhaps even giving different types of cells different laser signatures.

Hey what is this with you and strawberries man? what are you trying to do?? That is if you do not mind sharing!
And about messing with genes, they are, my Mamu is a Post Doc Research Scientist working there am there almost once every week

lolz...not really

Faisalabad? Can I get some info on Strawberry??

We went from Mangoes to Strawberries - a tangent. Kindly restrict the discussions or move them to the "Whatever" thread, they disrupt the flow of the thread.

Discussions are fine, but please restrict them in size and avoid tangents, I believe @SvenSvensonov already had this discussion with Armstrong a few pages back.

Thanks

 

[Fenrir]

This Material Wouldn't Melt, Even at the Center of the Earth

Researchers have discovered a material that could break the record for the highest melting point of any substance.

A team of Brown University engineers found that a combination of hafnium, nitrogen, and carbon, in just the right amounts, could withstand 4,400 kelvins, or around 7,460 degrees Fahrenheit. To give you an idea, that’s two-thirds the temperature of the sun’s surface. The outer core of the Earth can hit 4,300 kelvins, for further mind-blowing reference.

The team figured this out through a series of computer simulations that “[infer] melting points by simulating physical processes at the atomic level.” The results were published in the journal Physical Review B.

Possible uses — other than a ship that bores into the Earth’s core — include high performance heat shields.

According to a release from Brown:

The work could ultimately point toward new high-performance materials for a variety of uses, from plating for gas turbines to heat shields on high-speed aircraft. But whether the HfN0.38C0.51 compound itself will be a useful material isn’t clear.

The next step, which scientists are already tackling: Actually synthesizing the material and experimenting in a lab. Journey to the center of the Earth TBD.

 

[Arsalan]

Study

Well my study is on European berries I got bored and told my supervisor I wanted Pakistani strawberries to be included and he was like sure if you can get me some we can discuss it...Now I am in search for some ...No one is cooperative to answer my mails...


I will address you to explore my thread on fragaria ...It kind of explains what I am trying to do

you must have chosen Mango or Orange and then see how much response you get.. Strawberries are not very common in Pakistan. Still there are a lot of wild strawberries that you can find, perhaps you should consider visiting Muree and go for hiking in Galiyat, Auybia, Khansepur areas, all these have excellent access and accommodations facilities. If that is too much you can try Islamabad and stroll on the margalle hills, plenty of tracks there as well. If you want to up the game, go to Kaghan valley. Members from that area may be able to help as well. As for the AARI, i do not think anyone would be working on Strawberries here, again, that is not a very common crop. It have been only 7 8 years that we have started seeing on road side stand.
If you want to visit commercial farms, you can find some around Punjab University New campus in Lahore.

 

[Fenrir]

you must have chosen Mango or Orange and then see how much response you get.. Strawberries are not very common in Pakistan. Still there are a lot of wild strawberries that you can find, perhaps you should consider visiting Muree and go for hiking in Galiyat, Auybia, Khansepur areas, all these have excellent access and accommodations facilities. If that is too much you can try Islamabad and stroll on the margalle hills, plenty of tracks there as well. If you want to up the game, go to Kaghan valley. Members from that area may be able to help as well. As for the AARI, i do not think anyone would be working on Strawberries here, again, that is not a very common crop. It have been only 7 8 years that we have started seeing on road side stand.
If you want to visit commercial farms, you can find some around Punjab University New campus in Lahore.

Would you be so kind as to move your discussion here:

Whatever | Page 4007

This isn't a discussion thread. I welcome any contribution you have, but would rather it stick to the thread structure and spirit. Discussions disrupt the flow of information.

Thank you

NASA Continues Crashing Airplanes For Science

NASA doesn’t just crash rockets — sometimes, it crashes cheaper aircraft too. This week, it’s the turn of a Cessna 172, being gratuitously destroyed to help improve airplane’s black boxes.

The Emergency Location Transmitters (ELTs) in aircraft are supposed to send a distress signal in the event of a crash, but thanks to the forces at work when ground meets plane, things don’t always go to plan (see: MH370).

In an attempt to make better ELTs, NASA has been crash-testing the popular Cessna 172, to get more data on how ELTs perform in a real-world scenario. Earlier this month, the agency dropped a 172 onto tarmac; this time around, it crashed one into a patch of dirt, producing a more severe crash since the plane doesn’t slide along the ground, just dig in.

NASA’s focus isn’t on making ELTs indestructible. Rather, it’s on making sure that the ELTs work in crashes that are severe, but survivable — the kind of crash where you really want the rescue mission to find you ASAP. A 100-foot fall onto dirt looks quite traumatic, but there’s a fair chance that some of the occupants might have survived.

More importantly, the crash was covered by all manner of cameras from all sorts of angles. If you’ve ever wondered what a light aircraft accident looks like, now’s your chance.

 

[Arsalan]

Would you be so king as to move your discussion here:

Whatever | Page 4007

You are right, should not have continued with the discussion here.
Anyway, have already moved to the appropriate thread.

Sorry for inconvenience.

 

[Fenrir]

This Globe Holds Some Of The First Detailed Photographs Of Mars

Mariner 6 (top two rows) and Mariner 7 (center to down right and south pole) pictures printed and assembled on a Mars globe on March 20, 1970. Image credit: JPL

How do you organize photographs of an alien world in the era before computers? By printing them out and sticking them to a globe of the planet!

The Mariner flybys past Mars were our first up close and personal view of the red planet. After the quick glance of the planet provided by Mariner 4 in 1965, Mariner 6 and 7 arrived in 1969 for a more extensive survey of Mars.

Mars experienced its first dual flyby with the arrival of Mariner 6 and Mariner 7 in 1969. Image credit: NASA/JPL

Mariner 6 and Mariner 7 were a matched set of identical spacecraft, sent to fly past Mars as the first dual encounter with the planet in 1969. Mariner 6 made the first flyby with Mariner 7 tagging along just five days later. The experience of manoeuvring the first probe was used to improve instructions for the flyby for the second probe, programming the 11.8-kilogram Control Computer and Sequencer for autonomous control during the flyby.

They carried identical payloads with both near and far resolution cameras, infrared and ultraviolet spectrometers, an infrared radiometer, a celestial mechanics experiment, and an S-band occultation experiment.

Artist's concept of the Mariner 6 and 7 spacecraft. Image credit: NASA/JPL

Both probes carried identical television cameras: Camera A, a wide-area lens covering 1,000 kilometers x 1,000 kilometers with a 3 kilometer resolution, and Camera B, a telephoto lens covering 100 kilometers x 100 kilometers with a 300 meter resolution. The cameras alternated taking pictures so a new photo was taken every 42 seconds. Mariner 6 sent home a total of 75 images during its flyby (49 far, 26 near) and Mariner 7 sent home another 126 images (93 far, 33 near), a massive improvement over the measly 21 images returned by Mariner 4 five years earlier. The probe pair sent home 800 million bits of data during the two flybys.

Narrow angle images from Mariner 6. Image credit: NASA/JPL reprocessed by Ted Stryk

Fifty hours before closest approach to Mars on July 29th, 1969, Mariner 6 flipped on its scientific instruments and started scanning the planet. A cooling system failure knocked the infrared spectrometer out of service, but otherwise the mission succeeded as planned. Based on the mission findings, Mariner 7 was rerouted farther south than originally intended, prioritizing near-encounter photographs on the light side of the planet. In the global model of the planet, Mariner 6 took the two two rows of photographs, while photographs from Mariner 7 extend from the center to the bottom right and across the Martian pole.

Global view of Mars as seen by Mariner 7 during its approach. Image credit: NASA/JPL

While the photographs finally cleared up that the long dark features were not canals, both probes managed to find entirely cratered regions. Despite photographing 20% of the planet's surface, both probes missed the epic volcanoes and canyons that fascinate us today. In addition, the probes identified a predominantly carbon dioxide atmosphere (98%!) with a surface pressure of 6 to 7 millibars, about the same as about 30.5 kilometers altitude on Earth. The probes also found a polar icecap composed of frozen carbon dioxide, and nocturnal surface temperatures as low as -73°C at the equator and -125°C at the south pole. The spacecraft also further refined estimates of the mass, radius, and shape of Mars.

When Mariner 9 arrived at Mars in 1972, they quickly acquired far too many images for this technique to work. Instead, Mariner 9 was all about the Mars mosaics. ...assembled the hard way by hand-trimming photographs with scissors.

 

[Fenrir]

Incredible Robotic Water Strider Jumps Like the Real Thing

Researchers from South Korea have created a robotic insect that’s capable of jumping and landing on an aquatic surface, a unique mode of transportation found only in specialized animals.

To reproduce this jumping ability in a robot, Je-Sung Koh and colleagues from Seoul National University studied the way water striders do it. The resulting bio-inspired robots demonstrate that this extraordinary insectoid capability can be replicated in an artificial system. The results of this team’s work now appears in the latest edition of Science.

Water striders, a semi-aquatic arthropod, are specially evolved for the task. They feature an exceptionally low body mass and superhydrophobic, i.e. water repelling, legs. What’s more, water striders support themselves on their trasi—the center segment of their foot—by surface tension alone. When making their dramatic leaps, these insects can generate enough vertical force to jump from the water surface, which is an action that typically requires high momentum.

A water strider doing what it does best (Credit: Seoul National University)

By analyzing high-speed images, the researchers discovered that water striders rotate the curved tips of their legs inward with a force just below that which is required to break the water surface. The authors determined this degree of force — exactly 144 milli-Newtons/meter—by using a theoretical model of a flexible cylinder floating on liquid.

Also, the researchers observed that the water strider’s long legs accelerate gradually such that the water surface doesn’t retreat too quickly and lose contact with the legs. Remarkably, water striders can jump on water as high was when they jump on ground.

Water strider together with a robotic insect that can jump on water. (Credit: Seoul National University)

Armed with this knowledge, the researchers set about the task of creating a robotic analogue. The resulting at-scale jumping robot, which weighs in at a mere 68-milligrams, perfectly recreates the controlled acceleration of their biological counterparts. The researchers used a “torque reversal catapult” mechanism to produce the required small burst of initial torque.

“What was very important for us while building the jumping water robot was to make sure that the maximum force does not exceed the maximum surface tension force,” noted Je-Sung Koh in an accompanying video demonstration.

And like the water strider, the robotic insect maximizes its overall lift off force by sweeping its legs inward to maximize the time its legs can push against the surface of the water.

Thus, by combining all these critical factors—light weight, long limbs, and similar physical mechanisms—the researchers were able to create their robotic water strider.

 

[Fenrir]

The Lexus Hoverboard Is Real And I Rode It

Of all the future tech that has been immortalized in Hollywood films over the decades, nothing seems to captured sci-fi geeks’ (of which I am one) imaginations like the hoverboard. The concept seems simple enough yet a working model as remained tantalizingly out of reach. Until now. The Lexus hoverboard is a real thing and I rode it.

Most famously appearing in Robert Zemeckis’s 1989 Back to the Future II, the concept hoverboard is probably less simple than it seems. To make it work you’ve got to have technology that involves some form of anti-gravity device cost-effectively miniaturized to fit on a skateboard. In the same period of time that we’ve gone from the Motorola DynaTAC 8000X to the iPhone 6, we’ve only gone from leg-powered skateboards to a few electric-powered options.

There have been several attempts at creating a working hoverboard that have met with varying degrees of success. Notably, the Hendo Hoverboard is somewhere on that line between proof-of-concept and hoax.

From all reports the Hendo board looked like it was built in a basement and was noisy and almost unridable, even if it did levitate. The Lexus board I rode is a far cry from that. Whisper quiet and smooth as glass, the Lexus hoverboard is a fully polished piece of kit. If the Hendo board is a Model T Ford the Lexus board is, well… a Lexus.

Lexus actually isn’t really breaking any new ground here with their board. All they’re doing is applying existing technology: superconducting magnetic levitation. If you can supercool a superconductor you can get it to react in predictable but sort of amazing way to a magnetic field.

There are videos of people doing this with very small magnets so what Lexus and their scientific partners did was scale up the concept.

So what’s it like to ride? Unbelievably difficult yet at the same time unbelievably cool, both because you’re levitating and because the board is filled with magnets more than 300 degrees below zero.

First, the difficult part. As you can see in the video the board is set to a static, unladen ride height of about 3 or 4 inches. When Lexus’ pro skateboarder, er, hoverboarder Ross McGouran gets on, his weight compresses the boards ride height to about 2 inches. However, as I’m about 100 pounds heavier than Mr. McGouran, when I get on the ride height compresses to a scant one inch.

At one inch the board is still hovering just fine, however, as there are two magnets in each end of the board balancing on it, like walking a tightrope (which apparently I’m not much good at).

As my weight shifts off center, the one-inch ride height simply isn’t enough to prevent the edges of the board from touching the ground. On a device whose primary design is based on being frictionless, adding even the smallest bit of friction is enough to bring the party to a screeching halt (with me being the one doing the screeching).

As the day wore on I managed to pry Ross away to give me a few pointers. He basically said the best way to ride it is to cowboy up and just get a running start and use momentum to overcome any friction when the board touches down.

Unfortunately that method didn’t go quite as well as we expected (more screeching was involved) so my best effort ended up being a half kick push coast deal. But it worked! I actually managed to hover off the ground for a good 30 feet and that was the cool part.

In day-to-day life you don’t stop to realize that everything you do requires a certain level of friction and the resulting feedback that brings. With the hoverboard, all of that goes away and for a brief moment you feel nothing.

I wish I could explain it better than that, but the feeling is so unique that I have nothing else I can compare it to. The closest feeling that comes to it is ice skating, but even that’s like comparing the finest silk to 300 grit sandpaper.

Is this finally Marty McFly’s hoverboard fully realized, the one fans have been desperately waiting decades to see? Unfortunately not. The Lexus hoverboard requires you fill it with liquid nitrogen every 10 minutes or so, and only works if your local skate park has several hundred thousand dollars worth of magnets built into its surface. It’s also probably the most expensive vehicle Lexus currently produces, making its chances of hitting the store shelves anytime soon almost nil.

None of that is the point.

The point is that a car company has been pushing the boundaries of styling (love it or hate it) for the past few years is now pushing the boundaries of modern technology. By spending cubic dollars on an ad campaign they may have inadvertently helped advance a technology that makes the modern automobile obsolete.

Like someone else once said: “Roads? Where we’re going, we don’t need roads.”

 

[Fenrir]

Uh Oh, MIT Developed a Way To Make Robotic Hands Way More Like Our Own

Robotic arms have been around for decades now—but even though we humans like to compare these machines to our own bodies, robotic arms and hands are very, very limited when it comes to dexterity. According to a pair of MIT engineers, the key to making robotic hands more like our own is teaching them how to improvise.

Say you’re walking into the office, holding a coffee, a bag, your keys, and your phone. The coffee starts to slip. You might naturally use a wall or table to steady the coffee, while your pinky might loop the keys. Then your thumb and forefinger use the tabletop to get a better grip on the coffee, and your other hand might use a nearby chair to adjust its grip on the bag and phone. As if by magic you don’t drop anything.

You don’t actually think about any of this; your hands naturally use the environment to better adapt to challenges. It’s almost as if our hands have their own embedded intelligence—what MIT engineers call “intrinsic dexterity.”

Robotic hands, obviously, don’t have that natural dexterity—wry MIT nerds go a bit further, callings them “fairly ham-handed”—which means that they must be carefully programmed to carry out each task, since they can’t adapt and improvise the way our own hands and arms can. Sure, there are more complex robotic hands and arms out there, but what if you could teach a simplistic robotic one to use its environment for tasks. An MIT mechanical engineering professor named Alberto Rodriguez and a graduate student Nikhil Chavan-Dafle are doing just that.

The duo are developing a method to teach simple robotic hands to recognize the environment around it, and exploit that environment to become more dexterous. Let’s look at one of their examples from a new video about their work. In one example, the hand does something that seems unbelievably obvious to us, but is unbelievably complex for a robot: It uses a flat surface to roll an object to get a better grip on it.

In another example, it uses a “wall” to steady the object and readjust its handle on it.

It might seem stupidly obvious to us, but robots, obviously, aren’t the best improvisors. Rodriguez and Chavan-Dafle are trying to make them better at thinking holistically about tasks, utilizing everything around them to carry out their work. That means teaching the machine to anticipate the pressure and force it will need to interact with the environment—no easy task.

“Exploiting the environment is, and will be, important for robots and the research community,” says Rodriguez in an MIT story about their work. “Any applications where you have limitations in terms of payload or cost or complexity, areas like manufacturing, or surgery, or field operations, or even space exploration — whenever you have a gripper that is not dexterous like a human hand, this [method] gives you some of that dexterity.”

It’s an interesting, and thoroughly unsettling idea: Even simple robots can be taught to use the world around them to carry out tasks in far more complex ways than those for which they were designed.

 

[Fenrir]

This Is What They're Doing With Their Expired Food in Sweden

We waste an incredible amount of food—and a lot of it is because we just don’t like the way it looks. Here’s one way they’re dealing with that problem in Sweden.

These food powders (or FoPo, as they’ve named them) are the work of students at Sweden’s Lund University in their food product program, and are made by a fairly old process—essentially freeze-drying and powdering food that is on the verge of being thrown out.

Of course, an all-powdered food diet is an unappealing and not particularly healthy way to live—but the point of the project is not to introduce a new diet, it’s to find a way to get some use out of food that would otherwise be thrown away. And, as a supplement or a flavoring it’s a good way to solve one of the basic problems of food waste: How do you get people to eat fruits and vegetables that, while absolutely edible, don’t look how we expect them to?

 

[Fenrir]

This Flamethrowing Helicopter Is Helping Fight California's Wildfires

Water-bombing aircraft are pretty standard wildfire-fighting equipment. Helicopters that spew fire onto the forest? Not so much.

Although flying around an already-burning forest with a flaming propane tank might seem counterintuitive, there is logic to the Apocalypse Now madness. Think back to your fire triangle: by burning tinder that’s in the path of the advancing wildfire, firefighters can deny the fire fuel, helping bring it under control.

Controlled burns are normally achieved by deploying wilderness firefighters, who use hand tools to prepare the burn. The helicopter flamethrower — really just a propane or gasoline tank, suspended underneath a heli — lets firefighters ignite a burn in hard-to-reach or dangerous areas. Plus, it lets the pilots fly around with a flaming propane tank, which I’m guessing is the best thing anyone’s ever been paid to do.

CAL-FIRE has deployed a helicopter to help stem the advance of the Rocky Fire, which is burning virtually out of control in the Northern Bay Area. Footage of the helicopter doesn’t seem to be available, but this video (from 2009) should scratch that flaming-heli itch quite nicely.

 

[Fenrir]

Deep Sea Electricity May Have Kickstarted Life On Our Planet

Researchers created “chemical gardens” — chimney-like structures normally found at bubbling vents on the seafloor — in the laboratory. Via NASA/JPL-Caltech

Curious about how life got started on Earth 3.8 billion years ago? Here’s a thought: Why not recreate ancient hydrothermal vents in the lab, and see if they produce enough juice to power a lightbulb? That, at least, is what a bunch of scientists at the Jet Propulsion Lab decided to do—and the electrifying results are helping unravel life’s origin story.

Every living thing on Earth needs electricity, which is basically just the flow of charged particles across a gradient. In fact, our bodies are pulsing with electricity right now: Every time your heart beats or a synapse in your brain fires, tiny electric currents race through you. Some scientists believe life got its start by channeling free electricity from ‘chemical gardens’ at the bottom of the ocean. These chimney-shaped structures bubble up from the seafloor, producing natural electrochemical gradients, which could have helped the first strands of DNA assemble, or provided free energy to early microorganisms.

An alkali hydrothermal vent at the bottom of the Atlantic ocean known as the “Lost City.” Image via D. Kelley and M. Elend/University of Washington

But if deep sea chimneys jumpstarted life, they’d have needed to produce a meaningful amount of electricity. We can’t travel back 3.8 billion years to see if this was the case, but we can create artificial chimneys in the lab that mimic what we think was happening on the ancient Earth. So that’s what scientists did. They built a tiny, alkali chimney using iron sulfide and iron hydroxide, geologic materials that can conduct electricity. This miniaturized lab experiment produced just under a volt of juice — enough to turn on an LED light. Which the scientists, ever quick with the puns, found quite shocking.

“These chimneys can act like electrical wires on the seafloor,” said Laurie Barge of NASA’s Jet Propulsion Laboratory, lead author of a new paper on the findings. “We’re harnessing energy as the first life on Earth might have.”

So, little alkali iron chimneys, at least, might have produced enough power to stitch together the first DNA strands and proteins. Next up, the scientists plan on tinkering with the recipe, building chimneys out of other materials that were probably more common in Earth’s early oceans, such as molybdenum, nickel, hydrogen and CO2. They might start building chimneys that mimic conditions on ancient Mars, or in warm liquid oceans beneath Europa’s icy surface.

It’s crazy to imagine, but before we even get to Europa, we might have a pretty good idea whether there’s a free energy source for deep sea aliens to tap into. Just another day in science.

 

[Fenrir]

Flight Campaign Studies Radar Detection of Ice Crystal Icing

Flight Campaign Studies Radar Detection of Ice Crystal Icing | NASA

Understanding the capability of radar to detect high altitude icing is the goal of a NASA flight campaign about to begin in Fort Lauderdale, Florida. For the next three weeks, NASA researchers will be flying a DC-8 research plane, outfitted with state-of the-art radar and sophisticated meteorological probes to detect ice crystal icing conditions.

Current weather radar can detect rain, hail or ice particles, but is limited in its ability to discern which types and sizes of ice crystals are in the atmosphere. When ice crystals hit warm aircraft engines, they start to melt and evaporate, cooling the engine core surfaces to temperatures below freezing. This enables the melted ice crystal water to refreeze, causing ice to accumulate inside the engine core. Ice in this location may cause temporary power loss or engine blade damage.

The Florida flight campaign is the first NASA mission and the third in a series of investigations by industry and government researchers to develop a better understanding of ice crystal icing conditions. “We are collecting radar signatures of the icing environment while the meteorological probes measure the actual ice water content and sizes of the ice crystals that the plane flies through,” says Steve Harrah, principal investigator. “The goal is to develop design requirements for a new radar process that can detect ice crystal icing and discern these conditions from non-hazardous clouds and low ice particle concentrations. With this new information, pilots should be able to avoid danger in the future.”

Data collected from NASA’s research will define requirements for future commercial radar products, provide the avionics industry with good scientific principles and measures for the detection of ice crystal icing conditions, and add additional data for engine icing standards updated earlier this year.

Photo credit: NASA/Peter Merlin

 

[Fenrir]

Why are Drought Balls Black Instead of White?

Los Angeles has coated its reservoirs in millions of black plastic balls. But why are they a heat-absorbing black instead of light-reflecting white? Because they’re shade balls, and their purpose has nothing to do with the drought.

Switch between wearing a dark shirt and a light shirt on a sunny day and you’ll quickly be reminded that dark colours absorb light and heat up faster than lighter colours that reflect light. So why are those shade balls in the Los Angeles reservoirs black instead of white? Because their purpose is to be a cheap, durable, safe way of providing shade, but not to keep the reservoirs cool.

The balls are coated in carbon black, a food-safe pigment with an albedo near zero. Both these characteristics are vital for explaining why the balls are designed to be a dull light-absorbing black instead of a shiny light-reflecting white, and are a lot more important than a bit of heat.

The purpose of shade balls is to provide shade, not to prevent evaporation. The primary purpose of the shade balls is to block sunlight so the ultraviolet light doesn’t catalyze nasty chemical reactions. Chlorine can breakdown into bromate when exposed to UV light, which is a carcinogen that really should violate drinking water standards instead of merely being a thing it’s nice to minimize. It is a secondary benefit that the shade also reduces evaporation, a small but important smidgeon of water savings during the ongoing extreme drought.

A small portion of the 90 million black plastic balls added to the Los Angeles Reservoir on August 12, 2015. Image credit: AP/Damian Dovarganes

Carbon black is nearly-pure elemental carbon produced by burning hydrocarbons in an air-poor environment. It’s mainly used in rubbers (like car tires), but about 9% of it is used as a pigment in plastics and paints. Carbon black can pose a health risk when it’s a powder by irritating lungs, but as a pigment it’s locked safely away. It is used worldwide in food packaging, and meets the NSF/ANSI 61 standards for materials that come in contact with drinking water. This means the balls won’t do anything nasty to the water supply they are protecting.

Carbon black has an albedo near zero, which means it is incredibly dark and reflects almost no light. That in turn means that any sunlight is absorbed by the ball, not reflected or refracted. For thin plastics, black is opaque while white is translucent. Cheap, thin-walled black balls still provide actual shade while lighter colours permit sunlight to penetrate into the water. Blocking as much sunlight as possible is the name of the game for shade balls, so black is the better colour. In an interview with Mashable, a spokesperson from the ball-manufacturing company XavierC explains that this theory is backed up by their testing, “After decades of testing, black has been deemed the color that provides the best protection.”

Black will also help the balls survive longer. Ultraviolet light, the component of sunlight that gives us sunburns, is very effective at breaking down plastics. This is problematic by reducing the lifespan of the balls, and thus increasing the expense of replacing them. Carbon black will prevent the plastic from breaking down in UV light, giving them a multi-decade lifespan.

Floating plastic balls cast shade to protect water quality; any reduction in evaporation is just a bonus. Image credit: AP/Damian Dovarganes

Black balls will heat up more than white balls would, and might even bump the temperature in the reservoir. They also might not. Sunlight heats an uncovered reservoir not by directly heating individual water molecules, but by heating the bottom and that heat transferring to water through conduction. The warm, less-dense water on the bottom rises, and fresh, cooler, water sinks down to be heated in turn. In a covered reservoir, sunlight heats the top surface of floating balls instead. Water is still heated by conduction, but it stays at the top instead of circulating. That might slow down heat transfer. But either way, it isn’t very important.

As a final bonus, while black heats up faster than white, it also cools down faster. Anything that absorbs light readily emits it equally-readily, so when the sun sets a reservoir coated in black balls is going to cool down rapidly as heat is radiated into the night.

Top image: Four inch diameter black plastic shade ball. Credit: AP/Damian Dovarganes