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<p>In vitro fertilization is a costly, precisely timed process that takes two to three months per cycle. Covid-19 shut down fertility clinics and halted these cycles. What happens now?</p>

The pandemic disrupted tens of thousands of IVF cycles





  
      <p>When a diminutive 4-pound helicopter lifted off over a red landscape on Monday morning, it became the first craft to achieve controlled, powered flight on a planet beyond Earth.</p><p>At approximately 6:15 a.m. EDT on Monday, NASA’s Ingenuity Mars helicopter team—along with eager viewers from across the globe—watched live as data from the red planet arrived to Mission Control via a <a href="https://www.nasa.gov/directorates/heo/scan/services/networks/deep_space_network/about/">Deep Space Network antenna</a>. The data signified that Ingenuity’s flight, which occurred approximately four hours earlier, had been a success.</p><p>“Sometimes we have to do something just to show that we can do it,” NASA’s Associate Administrator for Science Thomas Zurbuchen said during <a href="https://www.youtube.com/watch?v=p1KolyCqICI">NASA’s livestream</a> of the event. “When the Wright brothers flew for the first time, they flew an experimental aircraft. And in the same way, the Mars helicopter is designed to show that we can fly a powered helicopter flight in the Martian atmosphere.”</p>
  

  
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      <p><a href="https://www.pbs.org/wgbh/nova/article/nasa-ingenuity-mars-helicopter-first-flight/">Getting Ingenuity to fly</a>, Ingenuity Project Manager MiMi Aung added, “was the unwavering dream of our team since day one.”</p><p>On Monday, downlink lead Michael Starch, clad in an orange Ingenuity team polo, studied his computer screen in the helicopter control room. “This is downlink. Early indications,” he said, looking up from the monitor. “Data products look nominal.”</p><p>Sitting close by was Aung, who visibly grinned under her mask.</p><p>“This is downlink,” Starch repeated. “We’ve pulled in data products from Mars 2020.” He pauses for 39 seconds. The room was silent. “This is downlink,” he said again. “Confirming we received Mars 2020 telemetry. Confirming we received Mars 2020 event. Confirming we received helicopter data products.” Starch nodded his head up and down.</p><p>Silence once again fell over the control room. Aung twiddled her fingers. Some teammates nodded. Others glanced at their laptops and then back at their anxiously-awaiting colleagues.</p><p>“This is downlink,” Starch said. “Confirming we have helicopter data products, helicopter telemetry, helicopter event… battery data has been received.”</p>
            <figure class="richtext-image full-width"><img alt="NASA JPL&amp;#x27;s Ingenuity Mars helicopter team" class="richtext-image full-width" height="533" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/25819_4-PIA24585-web.width-800.jpg"/><figcaption><p>Members of NASA’s Ingenuity helicopter team, including MiMi Aung (front), in NASA JPL’s Space Flight Operations Facility prepare to receive the data downlink showing whether the helicopter completed its first flight on April 19, 2021. Image credit: NASA/JPL-Caltech</p><div class="credit"></div></figcaption>
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            <p>Starch handed it off to Flight Control, which gave its announcement: “Ingenuity is reporting having performed spin-up, takeoff, climb, hover, descent, landing, touchdown and spin-down.”</p><p>Aung gave two thumbs up and then waved her fists. The control room erupted with clapping, originating from both mask-wearing team members in person and those watching over Zoom.</p><p>“Altimeter data confirmed,” Flight Control said. Cheers exploded from the control room. The altimeter plot of the flight, mechanical engineer Taryn Bailey explained during NASA’s livestream, indicates a peak. It starts off with a flat line, showing that Ingenuity is grounded, has a steep incline, indicating that the helicopter has spun up and risen, a dwell, showing that Ingenuity is hovering, and then another steep decline to the ground representing Ingenuity’s touchdown.</p><p>“Confirmed that Ingenuity has performed its first flight of a powered aircraft on another planet,” Flight Control said.</p>
  

  
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      <p>As the cheers and fist pumps continued, the team received its first picture from the mission: a black and white photo that Ingenuity snapped while hovering over the Martian surface, its shadow—four rotors, four legs, and a tissue box-like body—cast beneath it.</p><p>Getting Ingenuity to fly on Mars was no easy feat. This first flight, initially scheduled for Sunday, Apr. 11, was delayed after team engineers identified a potential problem. (The team decided to update Ingenuity’s flight control software before attempting a maiden flight.) And years of preparation back on Earth was necessary.</p><p>Starting in 2014, before testing Ingenuity, the team used helicopter models to simulate flight on Mars. These models were the precursors to Ingenuity and “went through extensive environmental and aerodynamic testing,” Bailey said.</p><p>To properly test these models and then Ingenuity beginning in 2019, “We had to simulate a Mars-like atmosphere,” which is 1% the density of Earth’s, Bailey explained. The team did this by using NASA’s Jet Propulsion Laboratory’s 25-foot space simulator thermal vacuum chamber, which allowed the team to control temperature and pressure to simulate Mars’ atmospheric density. The team also used a gravity off-load system to compensate for the difference in gravity between Earth and Mars, Bailey said.</p><p>After these tests “We said, ‘The next time we fly it’ll be on Mars,’” Aung said during a press conference on Apr. 9.</p>
            <figure class="richtext-image full-width"><img alt="The Ingenuity Mars helicopter, photographed by Perseverance" class="richtext-image full-width" height="594" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/25816_PIA24550-1200.width-800.jpg"/><figcaption><p>The first flight of NASA’s Ingenuity Mars Helicopter was captured in this image from Mastcam-Z, a pair of zoomable cameras aboard NASA’s Perseverance Mars rover on April 19, 2021. Image credit: NASA/JPL-Caltech</p><div class="credit"></div></figcaption>
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            <p>At four pounds, Ingenuity was built to be both light and fast, bolstering its ability to soar in Mars’ incredibly thin atmosphere. Despite its small size, the helicopter’s wingspan is 4 feet tip-to-tip: “super large for something that’s essentially carrying [a vehicle] the size of a tissue box,” Bailey said.</p><p>Each of its four blades is made of a lightweight but strong composite material and weighs less than 2 ounces—the equivalent of four empty soda cans. To generate lift in an incredibly-thin atmosphere with few molecules to push around, Ingenuity’s blades move at an average speed of 2,500 rotations per minute. (Helicopters used on Earth typically operate at 450 to 500 rpm.)</p><p>While Ingenuity’s first flight was modest—a 10-foot hover above the red planet’s surface and a touchdown—its upcoming four flights will increase in technical difficulty. The team hopes to eventually explore parts of Mars’ terrain that it can’t navigate with terrestrial rovers like <a href="https://www.pbs.org/wgbh/nova/article/nasa-perseverance-mars-rover-landing-success/">Perseverance</a>. “The rover has to navigate around a lot of obstacles on the ground that the helicopter can fly around,” Bailey said.</p><p>“We’ve sent five rovers to Mars and now we have an aerial dimension, which...elevates the next stage of space exploration,” she added. Ingenuity and its eventual successors may also allow for more collaboration and eventually open the doorway for human exploration of other worlds, Bailey said.</p><p>Though the Ingenuity team already received still images of the helicopter’s maiden flight from both Ingenuity and Perseverance, it expects to get video footage and more high-resolution images in the next couple of days. You can view these on <a href="https://mars.nasa.gov/mars2020/multimedia/raw-images/">NASA’s website here</a>.</p>
  

  
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Ingenuity’s first black-and-white picture from the air. Image credit: NASA/JPL-Caltech

<p>The 4-pound helicopter just became the first craft to achieve controlled, powered flight on a planet beyond Earth.</p>

Victory! Ingenuity conducts its first powered flight on Mars

Stanley Andrisse holds an MBA and Ph.D. His nonprofit organization From Prison Cells to PhD offers education counseling, mentoring, and support to 100+ currently and formerly incarcerated people annually. Image Credit: Tchad at Free Star Media

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      <p>NASA has delayed the first flight of its Ingenuity Mars helicopter, announcing that it expects to set a new date next week.</p><p>The helicopter, which arrived on the red planet tucked inside <a href="https://www.pbs.org/wgbh/nova/article/nasa-perseverance-mars-rover-landing-success/">the Perseverance rover</a> in February, was initially set to fly on Sunday, securing its position as the first rotorcraft to lift off on another world. Late on Friday night, however, a high-speed test of Ingenuity’s rotors <a href="https://mars.nasa.gov/technology/helicopter/status/291/mars-helicopter-flight-delayed-to-no-earlier-than-april-14/">ended early</a>: As the helicopter’s command sequence tried to transition the flight computer from “preflight” to “flight” mode, engineers were alerted to a potential problem. The team has decided to update Ingenuity’s flight control software before attempting a maiden flight.</p><p>During this first flight, the Ingenuity Mars helicopter will lift off, hover 10 feet above the Martian surface, take pictures, and touch back down—all in a period of about 40 seconds. Meanwhile, some 200 feet away, the Perseverance rover will snap pictures and videos of its companion’s brief voyage.</p>
  

  
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      <p>This first flight will be a modest beginning of a much more ambitious task: In the next 30 days, the Ingenuity team at NASA’s <a href="https://www.jpl.nasa.gov/">Jet Propulsion Laboratory</a> will attempt a total of five flights, each longer and more technical than the last.</p><p>“Each world only gets one first flight,” Ingenuity Project Manager MiMi Aung said during a press conference on Friday. It’s a “historic moment that has analogues in 1903,” NASA’s Associate Administrator for Science Thomas Zurbuchen added, referring to the year the <a href="https://www.pbs.org/wgbh/nova/article/unlikely-inventors/">Wright brothers</a> became the first in the world to fly a motor-operated airplane—after two failed liftoffs.</p><p>“History tells us that Orville and Wilbur took this setback like true engineers,” confirming that their fundamental understanding of flight was correct and going back and making subtle changes, Aung said during Friday’s press conference. Aung believes she and her team have become similarly well-versed in the unique challenges of flying a hovercraft on another planet and are aware that despite years of preparation, something could go wrong when it’s time for the first attempt. “I want to be conservative,” Aung said on Friday, adding the Ingenuity team had yet to celebrate the Mars helicopter’s achievements.</p><p>Perhaps the greatest challenge the team will face is the <a href="https://www.pbs.org/wgbh/nova/video/mars-facts-red-planet/">Martian atmosphere</a>. Made up of mostly carbon dioxide, Mars’ atmosphere is a mere 1% as thick as our own planet’s, which is primarily nitrogen. Its thinness makes it the equivalent of flying at three times the height of Mount Everest, Ingenuity chamber test engineer Amelia Quon said on Friday.</p><p>Rotorcrafts, including helicopters, fly by generating lift. As their blades spin, they push the air and this lifts the craft up, Aung explains. In a thin atmosphere, she says, there are fewer molecules to push, “so you need to spin much faster to get lift,” she says. While the blades of most Earthly helicopters operate at around 450 to 500 revolutions per minute, Ingenuity’s will move at 2,400 rpm.</p><p>Ingenuity’s rotors “are not something off the shelf; they’re really fine-tuned to maximize lift in a really thin atmosphere,” Aung said. Weighing in at about 35 grams, the rotors have a foam core for lightweightedness and are covered in carbon fiber, laid out in a grid, for optimal stiffness and strength.</p><p>Like its blades, the body of the Mars helicopter is also lightweight, at less than four pounds. “We couldn’t make this happen” with technology that existed 10 or 15 years ago, Aung said.</p><p>Mars’ strong winds also pose a challenge. If gusts become too strong before Ingenuity is scheduled to fly, there’s no way of automatically postponing or canceling the flight through Perseverance, Ingenuity Operations Lead Tim Canham explained during Friday’s press conference. This is because the Perseverance rover’s weather-determining system has no connection to Ingenuity. And Ingenuity has no way to right itself; if it fails to land right-side-up during any of its flights, its mission on Mars would end.</p>
  

  
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      <p>But there’s good news: Martian weather is easy to predict. “Weather on Mars tends to stay the same over a period of sols,” Canham explains. (At 24 hours, 39 minutes, and 35 seconds, a Martian sol is slightly longer than a day on Earth.) The Ingenuity team initially chose 12:30 p.m. Martian time Sunday, the equivalent of 11:00 p.m. EDT, for a potential first liftoff because the team calculated that’s when Ingenuity would have the most charged battery and Mars would have the calmest skies.</p><p>The team started testing in 2014 whether Ingenuity could successfully fly on another planet. We “made Mars on Earth,” Quon said, referring to NASA’s Jet Propulsion Laboratory’s 25-foot space simulator thermal vacuum chamber, which Voyager 1 and 2 were tested in before making their way into space and out of our solar system.</p><p>First, the team used a flight model to illustrate that lift is possible—picture a couple of hops and a crash landing—in a Martian-like environment. Then, in 2018, the team had the model spin up three feet in the air and turn. In 2019, NASA scientists took data from previous tests and applied them to testing the actual Ingenuity Mars helicopter.</p><p>If all goes well, during its first sol after taking to the sky, Ingenuity will transmit its black-and-white photos and flight summary data to Perseverance, which will transmit the data to scientists on Earth. In the following days, scientists expect to receive color imagery and more complex data from the flight.</p>
            <figure class="richtext-image full-width"><img alt="Perseverance_Selfie.jpg" class="richtext-image full-width" height="450" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/Perseverance_Selfie.width-800.jpg"/><figcaption><p>NASA’s Perseverance Mars rover took a selfie with the Ingenuity helicopter, seen here about 13 feet (3.9 meters) from the rover in this image taken April 6, 2021, the 46th Martian day, or sol, of the mission. Image credit: NASA/JPL-Caltech/MSSS</p><div class="credit"></div></figcaption>
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            <p>Canham is also eager to hear the sound of Ingenuity’s liftoff: Perseverance is equipped with a microphone specifically designed to survive on Mars—and capture the <a href="https://www.scientificamerican.com/article/perseverance-mars-rover-records-sound-of-rock-zapping-laser1/">snaps, crackles and pops of its sizzling stones</a>. It’s possible for the microphone to capture Ingenuity’s liftoff, but given its somewhat significant distance (more than 200 feet) from the helicopter, there are no guarantees. It’s “very touch and go on whether we’ll get anything,” Canham said on Friday. “But who knows.”</p><p>What’s more certain is that Perseverance will capture its own photos of Ingenuity’s first flight.</p><p>Before, during, and after Ingenuity’s 40-second airtime, Perseverance will snap six to seven photos a second using its onboard <a href="https://mars.nasa.gov/mars2020/spacecraft/instruments/mastcam-z/">Mastcam-Z cameras</a>, one with zoomed-in perspective and the other a zoomed-out perspective. (You can view images as they come in on <a href="http://go.nasa.gov/perseverance-raw-images">NASA’s website here</a>.)</p><p>The Ingenuity team expects its second flight to happen four days after its initial flight. And if that one goes well—the goal being to have the helicopter fly up to 15 feet—the team will move to an every-three-day flight cadence.</p><p>“We want to have fun” with the fourth and fifth flights, Aung said, suggesting that the team may venture at least 150 feet out and back from the helicopter’s takeoff site, possibly into never-before-seen territory. “This is all about the future. This is all about being a pathfinder,” she said, explaining that Ingenuity can inform how future space helicopters, which will be bigger and heavier, should function.</p><p>Like NASA’s <a href="https://www.nasa.gov/mission_pages/mars-pathfinder">first Mars rover</a>—the modest 23-pound microwave-sized Sojourner, which touched down on the red planet in 1997—Ingenuity is a “tech demonstration,” explained Zurbuchen, NASA’s Associate Administrator for Science. Similar to Sojourner’s brief mission on Mars, Zurbuchen believes, decades from now, we’ll look back on Ingenuity’s month of flight with awe and fondness.</p><p>“Ingenuity’s month will be an aggressive demonstration of what it can possibly do,” he said. And, teammate Elsa Jensen added, “Big Sister”—Perseverance—“will be watching.”</p>
  

  
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A close-up of Ingenuity taken on April 5 by Mastcam-Z, a pair of zoomable cameras aboard the Perseverance rover. Credit: NASA/JPL-Caltech/ASU.

<p>Want to fly a rotorcraft on another planet? Here’s what it takes.</p>

What to expect during NASA’s first-ever Mars helicopter flight





  
      <p>You’ve seen the images: floating islands of plastic in the ocean, marine life entangled in nets and lines. Whether in the ocean or on land, <a href="https://www.pbs.org/wgbh/nova/article/bacteria-plastic-biodegradable-pha-recycling/">plastic pollutants</a>—and their effects—are often visible.</p><p>But not all pollutants are.</p><p>“What most people don’t realize is that there has been pollution for a long time,” says Desiree Plata, an environmental engineer and chemist at the Massachusetts Institute of Technology (MIT). “Most of it we just can’t see.”</p><p>Enter methane, a colorless, odorless chemical that, like carbon dioxide and other greenhouse gases, contributes to climate change by collecting in our atmosphere and trapping radiation from the sun. Methane is emitted into the air by many sources, including <a href="https://www.nature.com/articles/d41586-021-00659-y">melting permafrost</a>, gassy cows, and oil and gas drilling sites. And it’s about <a href="https://www.scientificamerican.com/article/how-bad-of-a-greenhouse-gas-is-methane/">86 times more potent</a> than carbon dioxide, according to the Intergovernmental Panel on Climate Change.</p>
  

  
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      <p>Methane is the main ingredient in natural gas, which powers 48% of homes in the United States. Commercial natural gas is scented with odorants to make a potential gas leak detectable, alerting a resident to shut off their stove or track down the leak.</p><p>“I like to call methane ‘the elephant in the atmosphere,’” Plata says. “It’s the gas everyone should be talking about, but few people know about.”</p><p>But now, a team at MIT is producing sensors to allow people to “see” methane, and ultimately track down its sources and mitigate its harmful effects.</p><h3>Sensor technology: by chemicals, for chemicals</h3><p>These methane sensors, developed by chemist Tim Swager <a href="https://www.c2sense.com/gas-sensors">and his team</a> at MIT, vary in size depending on how large of an area a user would like to monitor. The sensors could be big, shaped like a laptop briefcase for easy carrying. Or they could be small, about the size of a sticker, and shaped like the flat chip in your credit card.</p><p>The sensors are inexpensive, low-power devices that can detect methane emissions in nature and at industrial sites, Swager said in an email. The company C2Sense is working with his team’s technology, which could be on the market within a few years.</p><p>Though they’re not yet licensed for commercial use, Swager’s methane sensors have the potential to be as widely used as the carbon monoxide detectors we have in our homes. Methane is present in natural, industrial, and agricultural environments, and sometimes leaches into drinking water through the ground <a href="https://www.health.state.mn.us/communities/environment/water/wells/waterquality/methane.html">in the form of tiny gas bubbles</a>, meaning that anyone—from a farmer to an engineer to a homeowner—could use a sensor to get a better idea of the chemical’s presence in their air or water.</p><p>All of Swager’s team’s sensors are powered by the same thing: chemical elements. Platinum and oxygen naturally react with methane, so they can be used in the sensors to detect methane in an environment, Swager explains.</p>
            <figure class="richtext-image full-width"><img alt="Methane_Bubbles.jpg" class="richtext-image full-width" height="450" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/Methane_Bubbles.width-800.jpg"/><figcaption><p>Ice-rich permafrost thaws in Alaska. The carbon stored in the formerly frozen ground is consumed by microbes, which release methane gas. Image credit: USGS</p><div class="credit"></div></figcaption>
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            <p>Here’s how: The platinum in the sensor reacts with oxygen in the atmosphere, bonding to create a chemical compound. This compound then reacts with any methane present in the surrounding environment. “Basically, you’re oxidizing the methane,” Swager says. This reaction between the platinum-oxygen compound and methane sets off the sensor, which sends a notification to a specialized device (for an industrial-use sensor) or a cell phone (for a personal-use sensor).</p><p>The sensor’s platinum and electrode sensing component “is very tiny—and that means that you could put it into lots of different structures,” says Plata, who’s not involved in Swager’s work. Unlike some other machinery that’s weighed down by the bulky essential technology within it, C2Sense’s sensors rely on very little to work, so they can be easily integrated into homes, barns, drilling sites, and other environments where methane is present.</p><p>Gas sensors that can detect volatile organic compounds, including methane, already exist. But they’re not tailored to detect methane alone, Swager said in an email, and require temperatures higher than 570 F to operate. This makes them both costly and potentially dangerous around high concentrations of methane, a flammable gas.</p><p>Conversely, Swager&#x27;s sensors can operate in ambient conditions and have low power requirements—they can run at <i>submicrowatts</i>—making them inexpensive to operate. And unlike existing sensors on the market, which generally need a battery pack or wiring to work, Swager&#x27;s sensors can be powered wirelessly and read by a smartphone.</p><p>Some of the smaller prototype methane sensors are 0.08 inch (2mm) cubes, approximately as thick as a nickel. They can potentially help pinpoint leaks in homes or wells, attaching physically to an area where methane may spew from. The sensors can also attach to a cell phone for on-the-go sensing, reporting the changes in air or water quality right to a “mobile-friendly sensor platform” on the phone, Swager explains.</p><p>That said, personal-use sensors may be a ways off, Swager cautions. Currently, odorants added to methane-containing gas serve as the main indicator for gas leaks in homes. Unfortunately, scent is only useful if you’re present and able to smell it. “Houses can blow up if there’s too much natural gas,” Swager says. When someone is away from their home or is unable to smell a leak, it’s harder to protect against a possible gas fire—<a href="https://www.nytimes.com/2020/02/26/us/columbia-gas-massachusetts.html">or worse, explosion</a>.</p>
  

  
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      <p>Another possible application for the sensors, Swager says, is to test well water, which <a href="https://www.usgs.gov/mission-areas/water-resources/science/domestic-private-supply-wells?qt-science_center_objects=0#qt-science_center_objects">millions of people</a> in the U.S. rely on. When methane is drilled underground, the gas sometimes escapes from the pipe it’s being pumped into, travels through the porous earth, and rises from the ground. “In the process of drilling down, you&#x27;ve created another pathway for the methane to reach the surface. It could come up 100 yards from the well pad depending on the location, even get into the groundwater,” Swager says. Because the gas is considered nontoxic by several state departments of public health, methane doesn’t have a <a href="https://www.rcap.org/resource/natural-gas-and-your-drinking-water-system/">Safe Drinking Water Act maximum contaminant level</a>. (Although the U.S. Department of the Interior suggests a <a href="https://extension.psu.edu/methane-gas-and-its-removal-from-water-wells">specific methane level</a> at which homeowners should vent their wells.)</p><p>Larger sensors can sense transient leaks (leaks that start and stop) over large swaths of land. Intended for use by engineers, park rangers, and other professionals, industrial-use sensors could identify methane leaks at natural gas drilling sites, where methane comes up from the earth; forests, where <a href="https://www.nationalgeographic.com/environment/article/trees-release-methane-what-it-means-climate-change">raging fires can emit</a> the chemical; or large farms, where <a href="https://www.smithsonianmag.com/smart-news/seaweed-fed-cows-burp-less-planet-warming-methane-180977296/">methane-emitting livestock</a> live.</p><p>Cattle farming is the <a href="https://www.epa.gov/ghgemissions/overview-greenhouse-gases#methane">leading cause of methane emissions</a> in the U.S., with nearly <a href="https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emissions#agriculture">2% of total greenhouse gas</a> emissions annually coming from the methane cows burp and fart (and the U.S. is the <a href="https://www.usda.gov/topics/animals/animal-production">world’s largest producer of beef</a>). Scientists have looked for ways to lower methane emissions from cattle farming, going so far as to put <a href="https://www.wired.co.uk/article/cows-climate-change-methane-stop">masks on cows to catch their burps</a>.</p><h3>Addressing the elephant in the room</h3><p>As methane and other greenhouse gases collect in the atmosphere, they “work as a blanket,” says Andra Garner, a climate scientist at Rowan University in New Jersey. “Methane is a much thicker and heavier blanket than carbon dioxide and if you add too many blankets, we start to get way too warm,” she explains.</p><p>Beyond climate change and immediate safety risks of methane, the health effects of being exposed to high levels of methane over a prolonged period of time are also a concern, but haven’t been thoroughly investigated. Communities that have dealt with large amounts of methane leaking into their air—like the residents of Belmont County, Ohio, where one of the <a href="https://www.nytimes.com/2019/12/16/climate/methane-leak-satellite.html">biggest methane leaks ever recorded</a> in the U.S. happened in 2018—have reported respiratory problems and dizziness after being exposed to methane gas. In-home methane sensors could notify residents of leaks when their noses can’t, just like carbon monoxide and smoke detectors do.</p><p>“You probably hear headlines all the time, ‘Everywhere we look for plastics in the environment, we find them,’” Plata says. “The same is true of most industrial chemicals, but the problem is I can’t pull out my cell phone and take a picture of [them]. Tim’s sensors are helping to close that gap.”</p><p>Being able to see where methane comes from is the first step to controlling its effects on our planet. “Any time we have more data, that’s better; we get a better handle on where these emissions are coming from,” Garner says. After all, Plata says, “Getting chemicals out of the environmental system is a bigger challenge than trying to keep them from getting there in the first place.”</p>
  

  
      

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Water flowing from a Weatherford, Texas resident's well ignites when he puts a flame to the well spigot. The U.S. Environmental Protection Agency had evidence a gas company's drilling operation contaminated his drinking water with explosive methane,  but withdrew its enforcement action, leaving the family with no useable water supply, according to a report obtained by The Associated Press. Image credit: Lm Otero/AP/Shutterstock

<p>Methane is a greenhouse gas 86 times as potent as carbon dioxide. What if we could see methane emissions in real time?</p>

Could tiny sensors keep methane out of our atmosphere—and homes?





  
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      <p>We are outraged and heartbroken by the murders of eight people in Georgia, including six women of Asian descent. Anti-Asian racism has deep roots in our country’s history, but should have no place in our country’s future. In these challenging times, with anti-Asian sentiment on the rise nationwide, we believe that silence itself can be a form of violence. As leaders in public media, we feel it is imperative for us to clearly state our opposition to misogyny, hatred and racism in all forms. And we join our chief executive, Jon Abbott, in extending heartfelt support for our Asian American/Pacific Islander friends and family, colleagues, staff and the communities we serve.</p>
  

  
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      <p>John Bredar, VP for National Programming, GBH</p><p>Raney Aronson-Rath, Executive Producer, FRONTLINE</p><p>Marsha Bemko, Executive Producer, ANTIQUES ROADSHOW</p><p>Julia Cort, Co-Executive Producer, NOVA</p><p>Denise DiIanni, Senior Executive in Charge, GBH STUDIO SIX</p><p>Laurie Donnelly, Executive Producer, GBH STUDIO SIX</p><p>Cameo George, Executive Producer, AMERICAN EXPERIENCE</p><p>Chris Schmidt, Co-Executive Producer, NOVA</p><p>Susanne Simpson, Executive Producer, MASTERPIECE</p><p>Judith Vecchione, Executive Producer, GBH STUDIO SIX</p>
  

  
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NOVA GBH Joint Anti-Racism Statement Hero

<p>This week’s tragic killings in Atlanta are a continuation of the anti-Asian racism the country has seen for the past year. The attached letter is a joint statement reflecting our collective stand against this racism and for a commitment to fostering inclusivity in our country.</p>

Joint statement against anti-AAPI racism





  
      <p>Despite the efforts of recycling programs and environmental education, it’s still hard for many of us to grasp just how much plastic humans produce. We are on track to produce a billion tons of plastic a year by 2050. Cumulatively, we’ve already produced more than 8.3 billion metric tons since 1950. That’s 20 times the weight of all human beings alive right now. </p><p>The systems we’ve developed for recycling that plastic are full of logistical, political, and economic obstacles, and the numbers show it. By 2015, three quarters of those <a href="https://www.pbs.org/wgbh/nova/article/76-of-all-plastic-ever-made-has-already-been-discarded/">8 billion metric tons of plastic were already out of use</a>, with 9% of it having been recycled and 12% incinerated. A whopping 79% wound up in landfills or the natural environment, destined to sit virtually unchanged for hundreds, if not thousands, of years.</p>
  

  
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      <p>It doesn’t have to be this way. “Plastic” is a category that encompasses a huge diversity of materials with one thing in common: They’re made of repeating chains of molecules known as “polymers” and can be molded or extruded while soft to take particular shapes. Until recently, we&#x27;ve only looked to petrochemicals (made from crude oil and natural gas) to create plastics with the properties we find so useful: the rigidity of takeout utensils, the flexibility of plastic films, the moisture barrier that contains greasy food. Although some less-common petroplastics are indeed biodegradable, bioplastics—which are often made from plant materials like sugar cane pulp, corn, or cassava and in many cases biodegrade after relatively short periods—may also be able to help address our big plastic problem.</p><p>Enter <i>polyhydroxyalkanoates,</i> also known as PHAs, polymers used to make biodegradable bioplastics from an unlikely source: bacteria guts. PHAs and other bioplastics seek to challenge our assumptions about what plastic can be, and companies like Danimer in Georgia and Mango Materials in California are betting big that their products can help make a dent in our plastic waste numbers. Danimer’s partnership with Bacardi will see that company unveiling PHA bottles in all of its liquor lines by 2023; it also has partnerships in the works with <a href="https://www.fastcompany.com/90569273/pepsi-nestle-and-bacardi-are-all-using-this-new-plastic-like-packaging-thats-compostable-anywhere">Nestle, Pepsico, and other giants</a> of single-use plastic. Meanwhile, Mango is making inroads into other plastic-reliant industries, like apparel. (Yes, your workout clothes have plastic in them.)</p><p>But PHAs aren’t new. They’ve been around for 35 years, and doubters like to point to Metabolix, a PHA company that seemed promising, grew quickly, and then collapsed in 2016. Metabolix and other would-be innovators have lived and died trying to “make PHAs happen.” Is now the time for this bioplastic to break through?</p>
  

  
      

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      <p><br/>You might not think plastic and beer have much in common, but in the case of PHAs, there’s some surprising overlap. The bio-based plastic is derived from what amounts to bacteria guts, a polymer the microorganisms use to turn food into energy stored away for a rainy day. To make that polymer into something usable for humans, PHA scientists and entrepreneurs grow the bacteria in big vats under specific conditions, feeding them with vegetable oil, sugar, or methane gas and waiting to harvest the results. So far, kinda like beer.</p><p>Here’s where it gets a little different. When the bacteria have gotten so full and roly-poly that they’re barely bacteria anymore—when their cells have gone from around 3% polymer to upwards of 95%—they’re subject to a purification process that bursts their membranes and brings the polymer out of solution. The resulting white powder is combined in pellets that then can be made into straws and takeout containers. Voila: plastic that’s not just made without fossil fuels but is also fully compostable, biodegrading in both your backyard and the ocean.</p><p>We’ve known about bacteria’s capacity to manufacture plastic since the 1920s. But it took until 1983 to figure out how to get the polymers from inside the bacteria into human hands and until quite recently for that to happen on a scale that could be commercialized. “If you think of what we knew in the early 20th century about bacteria, microscopy, evolution, all those things have rapidly evolved,” says Mango Materials CEO Molly Morse. Only in the last decade have we had the tool set to <a href="https://link.springer.com/chapter/10.1007/978-3-642-03287-5_2">make PHAs a reality</a>.</p>
            <figure class="richtext-image full-width"><img alt="small white plastic pellets" class="richtext-image full-width" height="600" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/biopolymer_pellets.width-800.jpg"/><figcaption><p>Pellets made from PHA biopolymers. Photo courtesy of Mango Materials</p><div class="credit"></div></figcaption>
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            <p>Now, there are over 150 types of PHAs, which differ based on the length of their molecules, how they’re structured, which microorganisms are producing them, and what those microorganisms are fed. The longer the molecule chains, the more flexible and stretchable the plastic is; the shorter they are, the more brittle the material becomes. PHAs melt and flow like petroplastics and they can be turned into sheets or molded into many forms. That makes them great for all kinds of applications with one thing in common: whether in backyard compost, in industrial composting facilities, or in the ocean, they’ll completely biodegrade within six months. </p><p>The big difference is that petroplastics are synthetic, and while bacteria may attempt to break them down, those organisms lack enzymes to break the plastics’ carbon-carbon bonds, making full degradation impossible. But since bacteria already use PHAs to store energy, they have built-in ways to both recognize and break them down. That’s what makes PHAs uniquely biodegradable—but only in specific settings. To understand why this is possible, “think about wood,” says Danimer Chief Technology Officer Phil Van Trump. If you build your desk out of wood, it won’t just disappear out of your house one day; it needs the right environment for that. “But in your yard, it’s a different story. Put it back in that environment, and bacteria and fungi will recognize it as food and start in on it.”</p>
  

  
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      <p>Of course, there are some drawbacks. In plastic-nerd parlance, PHAs have a “narrow processing window,” which means that their melting point and the point at which heat transforms them chemically into something else are only 10 degrees apart. That limits the ways they can be processed to stand in for petroplastics—for example, in materials that are subjected to very high heat or need very high mechanical strength, like airplane windshields, car bumpers, or bulletproof vests. But PHAs&#x27; biggest drawback is cost. Production is relatively expensive, especially the part of the process that draws the polymer out of the bacteria, says Amar Mohanty, a polymer and plastics engineer at the University of Guelph in Canada. Though there are different techniques for doing so, they often require large amounts of expensive chemicals like acetone or chloroform. “And to get a really purified polymer, you need to repeat the steps two or three times,” adds his colleague, fellow engineer Manjusri Misra.</p><p>PHAs, like other bioplastics, also release methane when they degrade under anaerobic conditions (like in landfills). Since methane is a major contributor to greenhouse gas emissions, some critics worry that if PHA products grow popular and then are improperly disposed of, they may end up contributing to the climate crisis. In response, Van Trump and Mohanty stress the importance of developing proper waste-disposal infrastructure along with PHA technology, including industrial composting and digesters. “There’s growing we need to do as a society with how much we stick in landfills,” Van Trump says. </p><p>In her work at Mango Materials, Morse has taken the methane release issue in a different direction, since Mango’s PHA bacteria actually feed on methane to grow their polymer. Mango has even partnered with Silicon Valley Clean Water in Redwood City, California, to build a digester on site and harness the methane coming off the city’s waste. At just that single location, Mango could produce up to 10 million pounds of PHA plastic per year.</p><p>And then there’s the question of toxicity. In a <a href="https://www.sciencedirect.com/science/article/pii/S0160412020320213">recent study</a>, Lisa Zimmerman, a biologist at Goethe University in Germany, tested 40 different bioplastics, including one PHA product, and found they were not on average any less toxic than regular plastics. And when chemicals from the bioplastics leached into an environment where Zimmerman was raising microorganisms, many of them (including those from the PHA product) exhibited the potential to simulate hormones and interrupt the organisms’ metabolisms. Since some of the products she tested were <i>not</i> toxic, Zimmerman sees her result as an impetus to increase industry transparency. “The problem is that the product composition is not made openly available, so it’s really hard for other producers to integrate those less harmful chemicals,” she says. “To scale up, it would really help if it was openly communicated what is in the product.” </p>
            <figure class="richtext-image full-width"><img alt="2 plastic caps and roll of plastic film" class="richtext-image full-width" height="396" width="800"
            src="https://www.pbs.org/wgbh/nova/media/images/Bioplastic_products.width-800.png"/><figcaption><p>Plastic caps (left) and film (right) produced from PHA biopolymers. Photos courtesy of Mango Materials</p><div class="credit"></div></figcaption>
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            <p>Still, all the people interviewed for this article see the current moment as a time with enormous potential for bioplastics. As recently as 2014, when Mango applied for funding through the National Science Foundation to work on marine plastic pollution, their application was denied because the foundation “didn’t believe <a href="https://www.iucn.org/resources/issues-briefs/marine-plastics">plastics in the ocean were a problem</a>,” Morse says. She’s seen huge societal change since then, even noticing a difference just within the period of the COVID-19 pandemic. “People are at home staring at their trash cans wondering where all this stuff is going,” she says. “We’ve seen interest in the past 12 months like never before.”</p>
  

  
      <p>Van Trump also sees a major change in the attitudes of the corporations Danimer is partnering with, like Pepsi, Nestle, and Bacardi, which now seem more willing to invest in solutions to the plastics problem. “We’re growing like a weed,” he says of Danimer, which just opened new facilities in Georgia and Kentucky. And Van Trump and Morse both point out that price and scale are intimately connected. Bioplastics like PHAs are competing against a petroplastics industry producing in simply enormous volumes, with some single plants producing a billion pounds a year—and economies of scale make it possible for petroplastics companies to keep their prices low. “The industry has had 70 to 80 years to optimize and build capacity,” Van Trump says. He holds out hope, though, that “when we get to the scales of the ‘traditional’ polymers, then costs will come down dramatically.”</p><p>In fact, Mohanty says the current problem for PHAs is the opposite of what it was in the days of Metabolix: too much demand and not enough production capacity. He expects the industry will grow into that demand in the coming decade, <a href="https://www.nytimes.com/2020/08/30/climate/oil-kenya-africa-plastics-trade.html">especially as widespread single-use petroplastic bans go into effect</a>. The key, in the meantime, is to educate consumers about their options and to build enough infrastructure that all those new PHA containers and films and straws <i>don’t</i> end up in landfills. Of our voracious plastic appetite, he says, “If we cannot stay away from it, we have to find ways to handle it.”</p>
  

  
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Drinking straws are one of many single-use plastic products that could potentially be produced using biopolymers. Image Credit: Phichai, Shutterstock

<p>Bioplastics called PHAs grow like beer and biodegrade like wood. And they may be able to help with our plastic waste problem.</p>

Brand: NOVA Next

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