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Life performs many astonishing feats of chemistry, building complex molecules that can take us years to figure out how to synthesize. And the thermodynamics of these reactions are often fascinating—in many cases, life lives on the edge, at risk of seeing critical reactions bog down and run in reverse.
Now, some researchers have figured out a way to force bacteria to run a chemical reaction in reverse. Rather than breaking down a simple molecule into carbon dioxide, the bacteria will ingest carbon dioxide and spit out formic acid, a chemical that already has lots of uses—and could be used as fuel or to sequester carbon. The secret? Force-feed the bacteria the raw ingredients for the chemical reaction.Enzymes and catalysis
The proteins that act as enzymes are nothing more than catalysts. The complex three-dimensional shapes of these proteins stabilize intermediate states of chemical reactions, lowering the energy required to reach them. This essentially lowers the energetic hill that has to be climbed to get between a set of reactants and a set of products. But if the overall energy of the reactants and products isn't very different, then that smaller hill will also let things run in the opposite direction: the enzyme will happily form a reaction intermediate from the product and spit out the original reactants.
Conspiracy theories, like the world being flat or the Moon landings faked, have proven notoriously difficult to stomp out. Add a partisan twist to the issue, and the challenge becomes even harder. Even near the end of his second term, barely a quarter of Republicans were willing to state that President Obama was born in the US.
If we're seeking to have an informed electorate, then this poses a bit of a problem. But a recent study suggests a very simple solution helps limit the appeal of conspiracy theories: news media literacy. This isn't knowledge of the news, per se, but knowledge of the companies and processes that help create the news. While the study doesn't identify how the two are connected, its authors suggest that an understanding of the media landscape helps foster a healthy skepticism.Literate
News media literacy is the catch-all term for understanding how bias, unconscious or otherwise, influences the creation and consumption of news. This includes an awareness of the priorities of news organizations as businesses and the influence that ownership can have on the slant of news articles. But it also comes down to issues like recognizing that we bring our own biases in to the news we consume, allowing two people to come away from the same article with very different information.
Science is rarely kind to "crypto-zoology," which posits the existence of "hidden" creatures such as yeti, chupacabra, and Korean unicorns. It used to be that you could return from the weekend in the woods to regale your Sasquatch-hunting friends with tales of mysterious nocturnal sounds, a chase in the darkness, and—dramatically pulling a bag from your pocket—a tuft of the unseen creature's hair that had caught on a tree branch! Maybe your friends believed; maybe they did not. But, in the end, who could say exactly what you might have found?
And then scientists came along, science-ing these kinds of wonderful stories into scientific oblivion using science-y mitochondrial and nuclear DNA testing of purported Sasquatch bits. Such results have never been kind to crypto-zoology, often turning up possum and human DNA rather than anything Sasquatch-y.
But, if I'm remembering my Alexander Pope correctly, humans love to keep looking for mysteries:
How can we, as WEIRD (Western, Educated, Industrialized, Rich, and Democratic) individuals, mitigate our catastrophic effects on the environment? Pretty much all recommendations start with this: eat less meat.
Like the other top recommendations—drive less and fly less—this is not super appealing to most of us. But beef production in the US uses more land, water, and fertilizer than any other form of agriculture, no matter which way you cut it. Whether you measure by calories or grams of protein generated, cows are the elephant in the room.
As of now, cattle eat not only local pasture, but also grains, hay, and grass that is grown elsewhere and stored. A recent analysis by an international team of researchers looked into what would change if the US switched to sustainable ranching, in which cattle eat only from local grasslands and agricultural byproducts.
Part of our fascination with cold-and-dry Mars is its warm-and-wet past. What was Mars like when it had liquid water? Did any life swim in it? And where did the water go?
The most obvious explanation for that last question is that Mars’ water slowly diffused into outer space. Because Mars is considerably smaller than the Earth, its interior cooled much more quickly. When the Red Planet’s magnetic field petered out around 4 billion years ago, the loss of this atmosphere-protecting shield would have allowed water vapor to escape.
But that’s not necessarily the whole story. Estimates of Mars’ initial store of water are generally larger than estimates of how much would have escaped to space in this way. What didn’t go up may have gone down—beneath the Martian surface.
As the adage goes, the dose makes the poison. But the same can be said for our foods—a morbid morsel to chew on during your holiday noshing.
While still safe to eat, our favorite dishes have a dark side—a striking amount are laced with toxic and deadly substances. In fact, we flirt with intriguingly dangerous ingredients not just during the holidays, but daily. Potentially poisonous substances arrive in our foods through contamination and hazardous production conditions, and toxins are also naturally present in many plants. Nearly all are present at such low amounts that they pose little risk. But, in large enough quantities or if safety monitoring fails, some of our favorite dishes could easily turn against us.
This leaves the Food and Drug Administration with the tricky task of keeping our foods safe—and knowing when they slip into the realm of poisons.
The weird thing about volcanic activity in the Western United States is that it’s actually quite difficult to explain. The Cascade volcanoes of the Pacific Northwest are one thing—standard tectonic plate boundary volcanoes like the rest of the Pacific Ring of Fire—but they are far from alone.
There is Yellowstone, of course, which has a history of frighteningly massive eruptions stretching across Idaho and into Wyoming. And neighboring the Cascades, a fair share of Washington and Oregon are blanketed by tremendous lava flows that erupted around 15 million years ago, while southeastern Oregon is home to Newberry Caldera and a line of related volcanoes. Nevada, meanwhile, is dotted by a string of smaller eruptions. (And we’re leaving out the Sierra Nevada Mountains and the Southwest entirely.)
There’s a lot of talk about a plume of hot mantle rock rising up beneath Yellowstone, which is what explains volcanic chains like the Hawaiian Islands. (The mantle plume stays in one place while the tectonic plate slides overhead.) But there is actually real disagreement about Yellowstone. Ultimately, this is because the last 50 million years in this region have been geologically wild, from the building of the Rocky Mountains to the stretching out of Nevada like an inhaling accordion and the creation of the San Andreas Fault. It’s… complicated.
‘Tis the season to be frisky. According to a new study this week in Scientific Reports, Christmas in the US often sees a spike in Google searches for sexy time topics and a surge in Tweets dripping with language denoting happy, care-free moods. The online frolicking is followed by a seasonal uptick in births about nine months later in September. And the US isn’t alone in this trend: the study shows other majority-Christian countries see similar climaxes in Internet romping around celebrations of the birth of Jesus. And majority-Muslim countries see them around Eid-Al-Fitr, a joyous religious celebration marking the end of Ramadan.
The authors of the study suggest that the online data may show, once and for all, that cultural factors—i.e. happy holidays—explain the yearly cyclical patterns of human reproduction. For decades, researchers have debated whether we’re seduced en masse by such cultural factors or whether collective moods are swayed by biological factors—responses to changes in daylight, temperature, and so on—or if it’s actually some mix of the two.
Global explanations for baby boom cycles have been tricky to figure out. Many countries have spotty data on births, and the study authors note it’s difficult to glean conclusions from things like condom sales and upticks in sexually transmitted diseases. But the advent of Google and Twitter data, they say, is a gift to human reproductive studies.
Our "The Greatest Leap" series is all about the triumph of humankind's first lunar landing, but putting the events surrounding Apollo into the right historical context necessarily requires a peek at what NASA is doing today and how the agency's modern approach to leaving low-Earth orbit mirrors—and differs from—what we did fifty years ago. Perhaps surprisingly to some, the near future of human space flight belongs not to orbiters and space planes, but to the old tried and true space capsule.
There are many reasons for this, but they tend to come down to the fact that at least with the current state of the art in materials science and aeronautics, the design attributes for the "plane" part tend to make it a terrible vehicle for atmospheric re-entry, and the attributes that make it a better re-entry vehicle tend to make it a terrible plane. Capsules, on the other hand, are essentially perfect space vehicles, sacrificing a spaceplane's "land almost anywhere if the runway is long enough" convenience for massively increased safety and predictability during re-entry (capsules are self-righting in the atmosphere, for example, while the Space Shuttle required constant active control as it returned to Earth).
The Georgia Public Service Commission (PSC) wants to keep two under-construction reactors at the Vogtle nuclear plant alive. According to a proposal offered by Commissioner Tim Echols and unanimously supported by the rest of the PSC, the plant will allow majority-owner Georgia Power to place some of the financial burden of completing the project on rate payers (that is, utility customers).
Vogtle is the only nuclear plant currently under construction in the US, and when it comes online it will be the first new nuclear plant to do so in three decades.
With some incentives for completion included in the PSC’s proposal, the reactors are now anticipated to come online in 2021 and 2022.
A central conceit of George R.R. Martin’s A Song of Ice and Fire books (and the popular HBO series Game of Thrones based on them) is that the seasons of the planet where they take place are not as predictable as the Earth’s annual cycle. Somehow the phrase “winter is coming” wouldn’t seem as foreboding if you could reply, “Yes, that usually happens in December through February.”
But how could a planet have unruly seasons? Earth’s seasons are due to the tilt of its axis. During one part of Earth’s orbit, the Northern Hemisphere is tilted away from the Sun, with the resulting indirect sunlight spread thin over the surface of the hemisphere, causing winter. On the opposite side of its orbit, summer comes as this hemisphere is tilted toward direct sunlight. There isn’t much room in such clockwork for randomness.
Well, if you’ve ever wanted to debate fan theories, here’s an excellent new resource for you to draw from: a real climate model simulation of Westeros and Essos.
The EECOM console—that is, the mission control console responsible for the electrical, environmental, and (initially) communications of the Apollo command and service module—wound up being home to an outsized number of famous names. Perhaps most famous is John Aaron, the "super EECOM" responsible for, among other things, the "SCE to aux" call that likely saved Apollo 12 from a mission-terminating launch abort. But equally skilled among EECOMs is T. Rodney ("Rod") Loe, who was kind enough to offer us an hour of his time to talk about his Apollo memories.
Loe would have been the EECOM sitting on the console during the Apollo 1 fire, if not for a simple coincidence: his wedding anniversary falls on January 27, the day of the fire, and on that day in 1967 Loe had swapped shifts with John Aaron so that he could celebrate with his wife Tina (she had arranged a celebratory poker game at their home for some friends).
We enjoy the life of plenty when it comes to technology. We like the speed at which information flows to us, carried on the back of hard-working photons. We wax lyrical, if a bit amateurishly, about the color and clarity of OLED televisions. Without our technological mastery of light, our society would be a good deal poorer.
That mastery, though, didn't appear out of thin air. It usually takes decades to go from the first "Wait, did that just glow?" to a technology being taken for granted.
So, what is the next big thing? No one really knows for sure, but I'm going to put in a good word for light-emitting metal-organic frameworks (MOFs). Light-emitting MOFs combine all the good things that we associate with organic light emitters with the best things about inorganic light emitters. If it all pans out, engineers will have a platform that has flexibility in design, simplicity in fabrication, and robustness in use. Before today, I wondered why I had not seen many results on light-emitting MOFs. And, now I realize that, like every other light-emitting technology, we are still in the "decade or more of work" phase with them.
If you’re a frequent Ars reader, you’ve likely heard of Kerbal Space Program, the space flight/space crashing/space explosion simulator that lets you create your own vehicles, then fly them into orbit and perhaps even to other planets. Though silly and fun, KSP also works as a reasonably solid and wonderfully interactive demonstration of the vagaries of orbital mechanics—and that, dear readers, gave us an idea.
Astronaut Scott Kelly is most famous for spending an uncomfortably long time on the International Space Station, and he’s currently touring to promote his book about the experience. We got to talk to him briefly when he was at the office back in October, but I wanted to take things a little further. What if we could sit down with Scott—a real astronaut who has flown the space shuttle and everything—and get him to talk us through a (somewhat realistic, somewhat silly) launch in KSP?
When the object 1I/2017 U1 ‘Oumuamua was first picked up by telescopes in October, there was no question that it was an odd duck—and that’s saying a lot considering that we recently explored a comet that looks like a duck. ‘Oumuamua seems to be a momentary visitor from another star system, punching through the plane of our Solar System from “above” like it hadn’t read our traffic signs. Oh, and it’s shaped like a cigar.
The list doesn’t end there. While it’s incredible to identify something that isn’t from our Solar System, it’s not a shock that such wanderers exist. Models of star and planet formation show that the growth of gas giants from the rotating disk of rubble that makes up an infant star system could easily fling some objects out into interstellar space. And since gas giants form beyond the “snow line”—the distance from the star at which water can begin to exist as ice—most of these exiles should be comets, which are composed primarily of ice and dust rather than solid rock.
But while ‘Oumuamua passed fairly close to the Sun, it showed no signs of the long tail that comets usually sport as warm sunlight turns ice to vapor. And that means there’s no ice on its surface. So what is it?
The Food and Drug Administration on Monday released a draft guidance (PDF) that will boost enforcement of manufacturing, marketing, and safety regulations for homeopathic products. The agency plans to specifically target what it considers high-risk products, such as those known to contain dangerous substances or are intended to be used for treating serious or life-threatening conditions.
Homeopaths, meanwhile, told Ars in a relatively subdued statement that they welcome the FDA’s efforts but are “hopeful that this action will not impede access.”
The FDA’s move follows a string of high-profile safety issues with homeopathic products. That includes a years-long investigation by the agency that linked illnesses in 400 infants and the deaths of 10 babies to improperly manufactured homeopathic teething products. In that case, FDA investigators confirmed that the products contained variable and sometimes high levels of toxic belladonna, aka deadly nightshade, which can have harmful and unpredictable effects in infants. With strong-arming, the FDA got the manufacturer, Hyland’s, to recall the products earlier this year.
A vast, gray expanse loomed just a few hundred meters below as Neil Armstrong peered out his tiny window. From inside the spidery lunar lander, a fragile cocoon with walls only about as thick as construction paper, the Apollo 11 commander finally had a clear view of where the on-board computer had directed him to land.
He did not like what he saw there. A big crater. Boulders strewn all around. A death trap.
Sea-level rise is one of the more challenging effects of climate change to project. It’s not that the direction of the change is unclear—sea level will rise as the planet warms—but it’s extraordinarily difficult to know when which sections of which glaciers will slide into the sea. Many factors are involved besides temperatures, including ocean currents and the topography of the bedrock below ice sheets.
As a result, the projections of sea-level rise presented to entities like the Intergovernmental Panel on Climate Change (IPCC) have been heavily caveated and have changed significantly over time. The 2013 IPCC report, for example, projected considerably higher sea-level rise than the 2007 report, which explained that it was leaving out important ice-sheet processes that needed more research. And the recent 2017 US National Climate Assessment again increased projections of sea-level rise based on the current state of the science.
A new study from a group of researchers led by Rutgers’ Bob Kopp has made for splashy headlines in recent days, some of which claimed the study showed that sea-level rise will be “worse than thought” or that the study confidently predicted how many people would be inundated by rising seas this century. Neither description is really true, as there is nothing new about the sea-level rise scenarios shown. In fact, Kopp also helped put together the sea-level chapter of the US National Climate Assessment, and the numbers in the new study obviously match those in the report.
The director of the Centers for Disease Control and Prevention fired off a series of tweets Sunday to try to quell fierce backlash from a Friday night report that the Trump administration had banned the agency from using certain terms in budget documents, including “science-based” and “diversity.”
“I want to assure you there are no banned words at CDC,” Director Dr. Brenda Fitzgerald tweeted at the top of a thread Sunday morning, which is currently pinned.
Instead, several sources have tried to clarify that the language changes were merely suggestions to help make the agency’s budget more palatable to some Republicans and ease its passage.
The story explaining the incredible flooding in Houston during Hurricane Harvey has many chapters, ranging from meteorology to the history of groundwater use and development zoning. The chapter on climate change has already had a few pages filled in, thanks to a study quickly published by MIT hurricane scientist Kerry Emanuel. This week, two complementary studies flesh the chapter out a little more.
The first paper comes from a group of scientists who have worked to rapidly analyze a number of extreme weather events over the past few years, including flooding in Europe and Louisiana last year. The general strategy for this type of undertaking is not entirely dissimilar from tracking the home run hitting of steroid-using baseball players. You can’t really know if an individual home run would have occurred sans steroids, but that’s not the point. Instead, you work out whether home runs like the one you just witnessed are generally being juiced.
In this case, the researchers were able to build on their analysis of the nearby Louisiana deluge from 2016. As in that study, they analyzed the history of rainfall measurements in the region to work out just how unusual the incredible rainfall totals from Harvey were—and whether the chances of an event like that have changed over time.