Today, you can buy a pair of sneakers partially made from carbon dioxide pulled out of the atmosphere. But measuring the carbon-reduction benefits of making that pair of sneakers with CO2 is complex. There’s the fossil fuel that stayed in the ground, a definite carbon savings. But what about the energy cost of cooling the CO2 into liquid form and transporting it to a production facility? And what about when your kid outgrows the shoes in six months and they can’t be recycled into a new product because those systems aren’t in place yet?

As companies try to reduce their carbon footprint, many are doing life cycle assessments to quantify the full carbon cost of products, from procurement of materials to energy use in manufacturing to product transport to user behavior and end-of-life disposal. It’s a mind-bogglingly difficult metric, but such bean-counting is needed to hold the planet to a livable temperature, says low-carbon systems expert Andrea Ramirez Ramirez of the Delft University of Technology in the Netherlands.
Carbon accounting is easy to get wrong, she says. Differences in starting points for determining a product’s “lifetime” or assumptions about the energy sources can all affect the math.

Carbon use can be reduced at many points along the production chain—by using renewable energy in the manufacturing process, for instance, or by adding atmospheric CO2 to the product. But if other points along the chain are energy-intensive or emit CO2, she notes, the final tally may show a positive rather than a negative number.

A product is carbon negative only when its production actually removes carbon from the environment, temporarily or permanently. The Global CO2 Initiative, with European and American universities, has created a set of LCA guidelines to standardize measurement so that carbon accounting is consistent and terms such as “carbon neutral” or “carbon negative” have a verifiable meaning.
In the rush to create products that can be touted as fighting climate change, however, some firms have been accused of “greenwashing” – making products or companies appear more environmentally friendly than they really are. Examples of greenwashing, according to a March 2022 analysis by mechanical engineers Grant Faber and Volker Sick of the University of Michigan in Ann Arbor include labeling plastic garbage bags as recyclable when their whole purpose is to be thrown away; using labels such as “eco-friendly” or “100% Natural” without official certification; and claiming a better carbon footprint without acknowledging the existence of even better choices. An example would be “fuel-efficient” sport utility vehicles, which are only fuel efficient when compared with other SUVs rather than with smaller cars, public transit or bicycles.

Good LCA analysis, Sick says, can distinguish companies that are carbon-friendly in name only, from those that are truly helping the world clear the air.

The James Webb Space Telescope has gotten the first sniff of carbon dioxide in the atmosphere of a planet in another solar system.

“It’s incontrovertible. It’s there. It’s definitely there,” says planetary scientist and study coauthor Peter Gao of the Carnegie Institution for Science in Washington, D.C. “There have been hints of carbon dioxide in previous observations, but never confirmed to such an extent.”

The finding, submitted to arXiv.org on August 24, marks the first detailed scientific result published from the new telescope. It also points the way to finding the same greenhouse gas in the atmospheres of smaller, rockier planets that are more like Earth.
The planet, dubbed WASP-39b, is huge and puffy. It’s a bit wider than Jupiter and about as massive as Saturn. And it orbits its star every four Earth days, making it scorching hot. Those features make it a terrible place to search for evidence of extraterrestrial life (SN: 4/19/16). But that combination of puffy atmosphere and frequent passes in front of its star makes it easy to observe, a perfect planet to put the new telescope through its paces.

James Webb, or JWST, launched in December 2021 and released its first images in July 2022 (SN: 7/11/22). For about eight hours in July, the telescope observed starlight that filtered through the planet’s thick atmosphere as the planet crossed between its star and JWST. As it did, molecules of carbon dioxide in the atmosphere absorbed specific wavelengths of that starlight.

Previous observations of WASP-39b with NASA’s now-defunct Spitzer Space Telescope had detected just a whiff of absorption at that same wavelength. But it wasn’t enough to convince astronomers that carbon dioxide was really there.

“I would not have bet more than a beer, at most a six pack, on that weird tentative hint of carbon dioxide from Spitzer,” says astronomer Nicolas Cowan of McGill University in Montreal, who was not involved with the new study. The JWST detection, on the other hand, “is rock solid,” he says. “I wouldn’t bet my firstborn because I love him too much. But I would bet a nice vacation.”

The JWST data also showed an extra bit of absorption at wavelengths close to those absorbed by carbon dioxide. “It’s a mystery molecule,” says astronomer Natalie Batalha of the University of California, Santa Cruz, who led the team behind the observation. “We have several suspects that we are interrogating.”
The amount of carbon dioxide in an exoplanet’s atmosphere can reveal details about how the planet formed (SN: 5/11/18). If the planet was bombarded with asteroids, that could have brought in more carbon and enriched the atmosphere with carbon dioxide. If radiation from the star stripped away some of the planet atmosphere’s lighter elements, that could make it appear richer in carbon dioxide too.

Despite needing a telescope as powerful as JWST to detect it, carbon dioxide might be in atmospheres all over the galaxy, hiding in plain sight. “Carbon dioxide is one of the few molecules that is present in the atmospheres of all solar system planets that have atmospheres,” Batalha says. “It’s your front-line molecule.”

Eventually, astronomers hope to use JWST to find carbon dioxide and other molecules in the atmospheres of small rocky planets, like the ones orbiting the star TRAPPIST-1 (SN: 12/13/17). Some of those planets, at just the right distances from their star to sustain liquid water, might be good places to look for signs of life. It’s yet to be seen whether JWST will detect those signs of life, but it will be able to detect carbon dioxide.

“My first thought when I saw these data was, ‘Wow, this is gonna work,’” Batalha says.

Sitting alone in the cockpit of a small biplane, Martin Wikelski listens for the pings of a machine by his side. The sonic beacons help the ecologist stalk death’s-head hawkmoths (Acherontia atropos) fluttering across the dark skies above Konstanz, Germany — about 80 kilometers north of the Swiss Alps.

The moths, nicknamed for the skull-and-crossbones pattern on their backs, migrate thousands of kilometers between northern Africa and the Alps during the spring and fall. Many migratory insects go where the wind takes them, says Ring Carde, an entomologist at the University of California, Riverside who is not a member of Wikelski’s team. Death’s-head hawkmoths appear to be anything but typical.

“When I follow them with a plane, I use very little gas,” says Wikelski, of the Max Planck Institute of Animal Behavior in Munich. “That shows me that they are supposedly choosing directions or areas that are probably supported by a little bit of updraft.”
A new analysis of data collected from 14 death’s-head hawkmoths suggest that these insects indeed pilot themselves, possibly relying in part on an internal compass attuned to Earth’s magnetic field. The moths not only fly along a straight path, they also stay the course even when winds change, Wikelski and colleagues report August 11 in Science.

The findings could help predict how the moths’ flight paths might shift as the globe continues warming, Wikelski says. Like many animals, death’s-head hawkmoths will probably move north in search of cooler temperatures, he suspects.

To keep tabs on the moths, Wikelski’s team glued radio transmitters to their backs, which is easier to do than one might expect. “Death’s-head hawkmoths are totally cool,” Wikelski says. They’re also huge. Weighing as much as three jellybeans, the moths are the largest in Europe. That makes attaching the tiny tags a cinch, though the moths don’t like it very much. “They talk to you, they shout at you a little bit,” he says.
Once the researchers set the newly tagged and slightly annoyed moths free, Wikelski took off after them in a plane. As the insects flew south toward the Alps, a device onboard pinged the transmitters at a frequency related to the moths’ distance from the plane.

While detailed tracking of eight of the moths allowed him to follow the insects for about 63 kilometers on average, he pursued one for just under 90 kilometers. That’s the longest distance that an insect has been continuously tracked, he says. “It’s outrageously crazy work,” he says of the night flights at low altitude. “It’s also a little dangerous and it’s just showing it’s possible.”

Once is apparently enough for male dark fishing spiders. After delivering only half of their available sperm to a single female, males curl up and wait for death.

In the considerable annals of spider sex ending badly, male Dolomedes tenebrosus suffer a fate not described before, says behavioral ecologist Steven K. Schwartz of the University of Nebraska-Lincoln. Males of this widespread North American species prepare sperm for two matings but spontaneously fall into a spidery version of a coma during the first one. Their legs crumple and their bodies hang terminally motionless without any sign of the female having injured them, Schwartz and his colleagues report June 18 in Biology Letters.
Male spiders deliver sperm via a pair of boxing-glove shaped projections, or pedipalps. Male dark fishing spiders load both pedipalps with sperm, but in lab and outdoor matings, males used only one before curling into a deathlike posture. Even when protected from any female attack, males’ hearts stopped beating about two hours after mating, Schwartz says.

If females eat the inert male, his death may gain him especially abundant or healthy offspring, Schwartz speculates. Or a recently fed female may be less likely to mate with the next suitor that comes along.

As dark male fishing spiders prepare to mate, the male (smaller than the female) rocks the female’s body. When he finally inserts one of his sperm-delivery organs into one of her reproductive openings, he suddenly collapses. He no longer responds when researchers pick up or poke at him.
Credit: S.K. Schwartz

A mysterious gap in a star’s dusty shell of debris could be the signature of a young planet circling its sun at twice the distance of Pluto’s orbit. If it does exist, the far-flung planet’s birth may be hard for astronomers to explain.

“If this is a planet, it is extremely challenging for existing planet formation theories,” says Katherine Kretke, an astronomer at the Southwest Research Institute in Boulder, Colo.

Most planets are thought to begin their lives as small clumps of hot, rapidly moving dust and gas within vast disks of debris that orbit newborn stars. As a planet grows it behaves like a snow plow, scooping up some material to bulk up while flinging other material away, until it has cleared a smooth orbital path.
John Debes, an astronomer at the Space Telescope Science Institute in Baltimore, used the Hubble Space Telescope to study a disk around TW Hydrae, a 10-million-year-old star located about 176 light-years from Earth.

Hubble images revealed an unmistakable gap 12 billion kilometers from the star, 80 times farther than Earth is from the sun. “It’s very striking,” says Phil Armitage, an astrophysicist at the University of Colorado Boulder. “It looks like what you’d expect from a forming planet.”

If the planet’s existence is confirmed, astronomers have their work cut out for them explaining how it got there. Compared with particles in tighter orbits, ones near that gap are less densely packed and move much more slowly, Kretke says. As a result, it would be difficult for a potential planet to accrue enough material to clear its own orbit.

An alternative theory of planet formation posits that clumps of gas within a disk can rapidly collapse together in a process similar to the one that forms stars. That could account for the outer bulky planets recently discovered around the star HR 8799 (SN Online: 12/3/10). But Kretke says that process is capable only of building worlds more massive than Jupiter, while this potential planet would be the size of Neptune or a large Earth.

“No matter how you look at it, if there’s a planet there it’s going to change theories of how planets form,” Debes says. His team’s results appear June 14 in the Astrophysical Journal.

The next step is to find the planet, Debes says, which will be no easy task. Just identifying the gap in TW Hydrae’s disk was akin to seeing a groove in an LP record from six kilometers away; now astronomers hope to find a speck hidden within that groove.

Debes notes that the Hubble photos were taken by a nearly 20-year-old instrument; he is confident that next-generation telescopes will see the planet if it exists.

Two drugs already on the market for other purposes can halt Ebola virus in mice. The findings open the way for further testing of the drugs, clomiphene and toremifene, against the deadly virus.

Scientists screened more than 2,000 drugs against Ebola, a process that required the highest level of safety precautions because the virus is so lethal. Several drugs called selective estrogen receptor modulators showed promise, including clomiphene, marketed as Clomid and prescribed to treat infertility, and toremifene, used to treat advanced breast cancer.
In the June 19 Science Translational Medicine, researchers report that each drug prevented Ebola virus from commandeering cells in lab-dish experiments. The researchers also injected mice with one form of the Ebola virus, and nine of 10 mice given clomiphene one hour after exposure survived a month-long observation period. Five of 10 mice getting toremifene died within 10 days, but the other five survived the month. All mice given the virus without the drugs died within a week.

The drugs bottled up Ebola in a cell compartment called an endosome, which the virus uses as a way station when it invades a cell. How the drugs thwart the virus there is unclear, says study coauthor Gene Olinger, a virologist at the U.S. Army Medical Research Institute of Infectious Diseases in Frederick, Md. But the results suggest that the drugs might stop other versions of the Ebola virus and the related Marburg virus, another deadly pathogen. In theory, the drugs would be given to patients and health care workers in an outbreak, he says.

“This is an interesting study, and it’s the way one wants to go with these viruses,” says Stephan Becker, a virologist at Philipps University in Marburg, Germany. Ebola burst on the scene in 1976 with deadly outbreaks in Zaire and Sudan. But it has been a sporadic menace, racking up about 2,300 victims worldwide. Despite a stunning mortality rate, Becker says, the small numbers suggest that the best strategy against Ebola is to repurpose drugs already cleared for other uses.

While testing an established drug for a new use is faster than starting from scratch, Olinger says, approval of these drugs for Ebola might still take five to 10 years. There is currently no cure for an Ebola infection.

Stone Age people may have carried land snails on a voyage from the Pyrenees to Ireland, an examination of the snails’ DNA reveals.

Scientists have struggled to explain why Ireland shares some plant and animal species with the Iberian Peninsula, but not with the rest of Europe or the British Isles. For example, Cepaea nemoralis land snails on Ireland’s western coast and in the southern Pyrenees share unique white-lipped shells.

To find out if the two populations of white-lipped snails are related, Angus Davison and Adele Grindon of the University of Nottingham in England took DNA samples from the species all over Europe. The researchers found that snails in Ireland and the Pyrenees share a variation in one gene that distinguishes them from other European specimens.

The simplest explanation, Davison and Grindon report June 19 in PLOS ONE, is that humans journeying to Ireland about 8,000 years ago brought along escargot as a food source. “Other explanations get quite convoluted,” Davison says.

A new, deadly respiratory virus spreads easily in hospital settings, a team of investigators has found.

The virus, called the Middle East respiratory syndrome coronavirus, or MERS, reminds Johns Hopkins University epidemiologist Trish Perl of SARS. “The cases are eerily similar,” she says. Perl and two colleagues investigated a SARS outbreak in Toronto 10 years ago. This spring, they helped unravel the chain of infection of a MERS outbreak in Saudi Arabia.

By examining medical records and carefully tracking where patients and hospital personnel had been, Perl’s team discovered that dialysis clinics played an important role in the outbreak. One man, designated Patient C, infected seven others, six of whom had undergone dialysis at the same time he did, the team reports June 19 in the New England Journal of Medicine. Patient C caught MERS from patient A, who was staying in the hospital room next door. Patient A ended up transmitting the virus to three people in total.
Once a person has been infected, it takes an average of 5.2 days for symptoms to appear and 7.6 days for MERS to spread to the next victim, the researchers calculate. MERS seems to spread earlier in the infection than SARS did. It is also more deadly.

SARS infected 8,098 people and killed 9.5 percent of them, or 774 people, between November 2002 and July 2003. To date, MERS has infected 64 people worldwide, killing 38, or about 59 percent. In the Saudi outbreak, 65 percent of the 23 people confirmed to have caught the virus died; most were elderly and had other health problems.

Laser pulses beamed from a low-flying airplane into northwestern Cambodia’s dense jungles have revealed ancient remnants of extensive, carefully planned settlements of rice farmers. These settlements were part of Angkor, the capital of the region’s Khmer empire.

Angkor flourished from around 900 to 1500, but forests now obscure much of the city’s urban sprawl. Laser technology called lidar has now seen through the jungle to the ground. It shows that, starting around 1100, roadways and canals formed rectangular grids — much like modern city blocks — around Angkor’s central temples and royal palaces, say archaeologist Damian Evans of the University of Sydney and his colleagues. Similar grids containing villages, ponds and small temples spread out far into the countryside over the next few centuries, covering as many as 1,000 square kilometers, the researchers report June 17 in the Proceedings of the National Academy of Sciences.

New probes of Angkor’s landscape support an increasingly popular idea: The city grew so large that its canals and reservoirs could not provide enough water when severe droughts hit around 1400. Residents may have gradually abandoned Angkor for cities built near rivers, in the region of today’s Phnom Penh.

Cabbages with jet lag are less nutritious and more vulnerable to insect pests.
Fruits and vegetables have an internal clock that can be reset by a daily cycle of light and dark, but storing produce in darkened refrigerators could disrupt this natural rhythm, researchers report June 20 in Current Biology.

Plants, even after being cropped from the stalk, are much more responsive to their external environment than we give them credit for, says Janet Braam, a plant biologist at Rice University. “When we harvest them they’re still metabolizing,” she says. “They’re still alive.”
Braam normally studies circadian rhythms in plants that are growing, but an offhand comment by her son inspired her to turn to the grocery store for new research subjects.

She and her colleagues had previously found that the plant Arabidopsis thaliana schedules production of insect-repelling chemical defenses to match caterpillar feeding peaks. These defenses include compounds called glucosinolates, which are thought to have anticancer and antimicrobial properties in addition to their caterpillar-discouraging ones.

When Braam told her son about these experiments, he joked that now he knew the best time to eat his vegetables. She realized that cabbages — which also produce glucosinolates — might have similar daily cycles even after being picked, packed and shipped.

“So we went to the grocery store, bought some cabbage and put them under dark/light cycles that were either in phase or out of phase with our insects, and then asked whether the insects could tell the difference,” says Braam.

Like Arabidopsis, the cabbage leaves had daily glucosinolate cycles if the vegetables were exposed to alternating 12-hour periods of light and dark. Caterpillars on a cycle offset by 12 hours to the cabbages’ (so the cabbages’ dawn was the caterpillars’ dusk) ate about 20 times more than did caterpillars on a schedule synchronized to their food. Caterpillars also ate twice as much cabbage if the vegetable had been kept either in constant light or constant darkness.

It’s not just cabbages that adjust daily rhythm to better fend off caterpillars; the team found similar results for spinach, zucchini, sweet potatoes, carrots and blueberries. These fruits and vegetables don’t produce glucosinolates, so they must make some other kind of defenses on a daily cycle, says Braam.

The researchers suggest that we might improve the health benefits and pest resistance of fruits and vegetables by storing them under lighting conditions that mimic day and night. But Cathie Martin, a plant biologist at the John Innes Centre in England, is skeptical. She says most postharvest vegetable losses are from fungal infections, not the insects that eat vegetables in the field. And cabbages are sometimes cold-stored for months in the dark before being sold. Cabbages lose the clock-regulated pest resistance about a week after harvesting, the new study shows.

“But maybe I’ll be proven completely wrong,” says Martin. “Maybe one day we’ll all have little LEDs in the fridge.”