How sleep may boost creativity

The twilight time between fully awake and sound asleep may be packed with creative potential.

People who recently drifted off into a light sleep later had problem-solving power, scientists report December 8 in Science Advances. The results help demystify the fleeting early moments of sleep and may even point out ways to boost creativity.

Prolific inventor and catnapper Thomas Edison was rumored to chase those twilight moments. He was said to fall asleep in a chair holding two steel ball bearings over metal pans. As he drifted off, the balls would fall. The ensuing clatter would wake him, and he could rescue his inventive ideas before they were lost to the depths of sleep.

Delphine Oudiette, a cognitive neuroscientist at the Paris Brain Institute, and colleagues took inspiration from Edison’s method of cultivating creativity. She and her colleagues brought 103 healthy people to their lab to solve a tricky number problem. The volunteers were asked to convert a string of numbers into a shorter sequence, following two simple rules. What the volunteers weren’t told was that there was an easy trick: The second number in the sequence would always be the correct final number, too. Once discovered, this cheat code dramatically cut the solving time.
After doing 60 of these trials on a computer, the volunteers earned a 20-minute break in a quiet, dark room. Reclined and holding an equivalent of Edison’s “alarm clock” (a light drinking bottle in one dangling hand), participants were asked to close their eyes and rest or sleep if they desired. All the while, electrodes monitored their brain waves.

About half of the participants stayed awake. Twenty-four fell asleep and stayed in the shallow, fleeting stage of sleep called N1. Fourteen people progressed to a deeper stage of sleep called N2.

After their rest, participants returned to their number problem. The researchers saw a stark difference between the groups: People who had fallen into a shallow, early sleep were 2.7 times as likely to spot the hidden trick as people who didn’t fall asleep, and 5.8 times as likely to spot it as people who had reached the deeper N2 stage.

Such drastic differences in these types of experiments are rare, Oudiette says. “We were quite astonished by the extent of the results.” The researchers also identified a “creative cocktail of brain waves,” as Oudiette puts it, that seemed to accompany this twilight stage — a mixture of alpha brain waves that usually mark relaxation mingled with the delta waves of deeper sleep.

The study doesn’t show that the time spent in N1 actually triggered the later realization, cautions John Kounios, a cognitive neuroscientist at Drexel University in Philadelphia who cowrote the 2015 book The Eureka Factor: Aha Moments, Creative Insight, and the Brain. “It could have been possible that grappling with the problem and initiating an incubation process caused both N1 and the subsequent insight,” he says, making N1 a “by-product of the processes that caused insight rather than the cause.”

More work is needed to untangle the connection between N1 and creativity, Oudiette says. But the results raise a tantalizing possibility, one that harkens to Edison’s self-optimizations: People might be able to learn to reach that twilight stage of sleep, or to produce the cocktail of brain waves associated with creativity on demand.

It seems Edison was onto something about the creative powers of nodding off. But don’t put too much stock in his habits. He is also said to have considered sleep “a criminal waste of time.”

In 2021, COVID-19 vaccines were put to the test. Here’s what we learned

2021 was the year the COVID-19 vaccines had to prove their mettle. We started the year full of hope: With vaccines in hand in record-breaking time and their rollout ramping up, we’d get shots in arms, curb this pandemic and get life back to normal. That was too optimistic.

Roughly 200 million people in the United States — and billions globally — have now been fully vaccinated. Three vaccines — one from Pfizer and its partner BioNTech, and the other two from Moderna and Johnson & Johnson — are available in the United States. Pfizer’s is even available for children as young as 5. About two dozen other vaccines have also been deployed in other parts of the world. In some higher-income countries, the United States included, people have already queued up for booster shots.

But 2021 has also been the year of learning the limits of the vaccines’ superpowers. With the vaccines pitted against aggressive coronavirus variants, inequitable distribution, some people’s hesitancy and the natural course of waning effectiveness, there’s still a lot of work to do to bring this pandemic to an end. As if to hammer home that point, the detection of the omicron variant in late November brought new uncertainty to the pandemic’s trajectory. Here are some of the top lessons we’ve learned in the first year of the COVID-19 vaccine. — Macon Morehouse
The shots work, even against emerging variants
Many COVID-19 vaccines proved effective over the last year, particularly at preventing severe disease and death (SN: 10/9/21 & 10/23/21, p. 4). That’s true even with the emergence of more transmissible coronavirus variants.

In January, in the midst of a bleak winter surge that saw average daily cases in the United States peaking at nearly 250,000, the vaccination rollout here began in earnest. Soon after, case numbers began a steep decline.

Over the summer, though, more reports of coronavirus infections in vaccinated people began to pop up. Protection against infection becomes less robust in the months following vaccination in people who received Pfizer’s or Moderna’s mRNA vaccines, multiple studies have shown (SN Online: 9/21/21). Yet the shots’ original target — preventing hospitalization — has held steady, with an efficacy of about 80 percent to 95 percent.
A single dose of Johnson & Johnson’s vaccine is less effective at preventing symptoms or keeping people out of the hospital than the mRNA jabs. The company claims there’s not yet evidence that the protection wanes. But even if that protection is not waning, some real-world data hint that the shot may not be as effective as clinical trials suggested (SN Online: 10/19/21).

Evidence of waning or lower protection ultimately pushed the United States and some other countries to green-light COVID-19 booster shots for adults (SN: 12/4/21, p. 6).

Much of the worry over waning immunity came amid the spread of highly contagious variants, including alpha, first identified in the United Kingdom in September 2020, and delta, first detected in India in October 2020 (SN Online: 7/30/21). Today, delta is the predominant variant globally.

The good news is that vaccinated people aren’t unarmed against these mutated foes. The immune system launches a multipronged attack against invaders, so the response can handle small molecular tweaks to viruses, says Nina Luning Prak, an immunologist at the University of Pennsylvania. Dealing with variants “is what the immune system does.”
Vaccine-prompted antibodies still attack alpha and delta, though slightly less well than they tackle the original virus that emerged in Wuhan, China, two years ago. Antibodies also still recognize more immune-evasive variants such as beta, first identified in South Africa in May 2020, and gamma, identified in Brazil in November 2020. Although protection against infection dips against many of these variants, vaccinated people remain much less likely to be hospitalized compared with unvaccinated people.
Experts will continue to track how well the vaccines are doing, especially as new variants, like omicron, emerge. In late November, the World Health Organization designated the omicron variant as the latest variant of concern after researchers in South Africa and Botswana warned that it carries several worrisome mutations. Preliminary studies suggest that, so far, omicron is spreading fast in places including South Africa and the United Kingdom, and can reinfect people who have already recovered from an infection. The variant might be at least as transmissible as delta, though that’s still far from certain, according to a December 9 report from researchers with Public Health England, a U.K. health agency. How omicron may affect vaccine effectiveness is also unclear. Pfizer’s two-dose shot, for instance, may be about 30 percent effective at preventing symptoms from omicron infections while a booster could bring effectiveness back up to more than 70 percent, according to estimates from Public Health England. But those estimates are based on low case numbers and could change as omicron spreads.

“This is the first time in history that we’re basically monitoring virus mutations in real time,” says Müge Çevik, an infectious diseases physician and virologist at the University of St. Andrews in Scotland. “This is what the viruses do. It’s just that we’re seeing it because we’re looking for it.”

But it’s unlikely that any new variant will take us back to square one, Çevik says. Because of the immune system’s varied defenses, it will be difficult for a coronavirus variant to become completely resistant to vaccine-induced protection. The vaccines are giving our immune systems the tools to fight back. — Erin Garcia de Jesús

The shots are safe, with few serious side effects
With billions of doses distributed around the world, the shots have proved not only effective, but also remarkably safe, with few serious side effects.

“We have so much safety data on these vaccines,” says Kawsar Talaat, an infectious diseases physician at the Johns Hopkins Bloomberg School of Public Health. “I don’t know of any vaccines that have been scrutinized to the same extent.”

Commonly reported side effects include pain, redness or swelling at the spot of the shot, muscle aches, fatigue, fever, chills or a headache. These symptoms usually last only a day or two.
More rare and serious side effects have been noted. But none are unique to these shots; other vaccines — plus infectious diseases, including COVID-19 — also cause these complications.

One example is inflammation of the heart muscle, known as myocarditis, or of the sac around the heart, pericarditis. Current estimates are a bit squishy since existing studies have different populations and other variables (SN Online: 10/19/21). Two large studies in Israel estimated that the risk of myocarditis after an mRNA vaccine is about 4 of every 100,000 males and 0.23 to 0.46 of every 100,000 females, researchers reported in October in the New England Journal of Medicine. Yet members of Kaiser Permanente Southern California who had gotten mRNA vaccines developed myocarditis at a much lower rate: 5.8 cases for every 1 million second doses given, researchers reported, also in October, in JAMA Internal Medicine.

What all the studies have in common is that young males in their teens and 20s are at highest risk of developing the side effect, and that risk is highest after the second vaccine dose (SN Online: 6/23/21). But it’s still fairly rare, topping out at about 15 cases for every 100,000 vaccinated males ages 16 to 19, according to the larger of the two Israeli studies. Males in that age group are also at the highest risk of getting myocarditis and pericarditis from any cause, including from COVID-19.
Components of the mRNA vaccines may also cause allergic reactions, including potentially life-threatening anaphylaxis. The U.S. Centers for Disease Control and Prevention calculated that anaphylaxis happens at a rate of about 0.025 to 0.047 cases for every 10,000 vaccine doses given.

But a study of almost 65,000 health care system employees in Massachusetts suggests the rate may be as high as 2.47 per 10,000 vaccinations, researchers reported in March in JAMA. Still, that rate is low, and people with previous histories of anaphylaxis have gotten the shots without problem. Even people who developed anaphylaxis after a first shot were able to get fully vaccinated if the second dose was broken down into smaller doses (SN Online: 6/1/21).

The only side effect of the COVID-19 vaccines not seen with other vaccines is a rare combination of blood clots accompanied by low numbers of blood-clotting platelets. Called thrombosis with thrombocytopenia syndrome, or TTS, it’s most common among women younger than 50 who got the Johnson & Johnson vaccine or a similar vaccine made by AstraZeneca that’s used around the world (SN Online: 4/23/21).
About 5 to 6 TTS cases were reported for every 1 million doses of the J&J vaccine, the company reported to the U.S. Food and Drug Administration. The clots may result from antibodies triggering a person’s platelets to form clots (SN Online: 4/16/21). Such antibodies also cause blood clots in COVID-19 patients, and the risk of developing strokes or clots from the disease is much higher than with the vaccine, Talaat says. In one study, 42.8 of every 1 million COVID-19 patients developed one type of blood clot in the brain, and 392.3 per 1 million developed a type of abdominal blood clot, researchers reported in EClinicalMedicine in September.

“Your chances of getting any of these side effects, except for the sore arm, from an illness with COVID are much higher” than from the vaccines, Talaat says. — Tina Hesman Saey

Getting everyone vaccinated is … complicated
The quest to vaccinate as many people as quickly as possible this year faced two main challenges: getting the vaccine to people and convincing them to take it. Strategies employed so far — incentives, mandates and making shots accessible — have had varying levels of success.

“It’s an incredibly ambitious goal to try to get the large majority of the country and the globe vaccinated in a very short time period with a brand-new vaccine,” says psychologist Gretchen Chapman of Carnegie Mellon University in Pittsburgh, who researches vaccine acceptance. Usually “it takes a number of years before you get that kind of coverage.”
Globally, that’s sure to be the case due to a lack of access to vaccines, particularly in middle- and lower-income countries. The World Health Organization set a goal to have 40 percent of people in all countries vaccinated by year’s end. But dozens of countries, mostly in Africa and parts of Asia, are likely to fall far short of that goal.

In contrast, the United States and other wealthy countries got their hands on more than enough doses. Here, the push to vaccinate started out with a scramble to reserve scarce appointments for a free shot at limited vaccination sites. But by late spring, eligible people could pop into their pharmacy or grocery store. Some workplaces offered vaccines on-site. For underserved communities that may have a harder time accessing such vaccines, more targeted approaches where shots are delivered by trusted sources at community events proved they could boost vaccination numbers (SN Online: 6/18/21).

Simply making the shot easy to get has driven much of the progress made so far, Chapman says. But getting people who are less enthusiastic has proved more challenging. Many governments and companies have tried to prod people, initially with incentives, later with mandates.
Free doughnuts, direct cash payments and entry into million-dollar lottery jackpots were among the many perks rolled out. Before the pandemic, such incentives had been shown to prompt some people to get vaccines, says Harsha Thirumurthy, a behavioral economist at the University of Pennsylvania. This time, those incentives made little difference nationwide, Thirumurthy and his colleagues reported in September in a preliminary study posted to SSRN, a social sciences preprint website. “It’s possible they moved the needle 1 or 2 percentage points, but we’ve ruled out that they had a large effect,” he says. Some studies of incentives offered by individual states have found a marginal benefit.

“People who are worried about side effects or safety are going to be more difficult to reach,” says Melanie Kornides, an epidemiologist at the University of Pennsylvania. And with vaccination status tangled up in personal identity, “you’re just not going to influence lots of people with a mass communication campaign right now; it’s really about individual conversations,” she says, preferably with someone trusted.
“Or,” she adds, “they’re going to respond to mandates.” Historically, sticks such as being fired from a job or barred from school are the most effective way of boosting vaccination rates, Kornides says. For example, hospitals that require flu shots for workers tend to have higher vaccination rates than those that don’t. For decades, mandates in schools have helped push vaccination rates up for diseases like measles and chickenpox, she says.

As COVID-19 mandates went into effect in the fall, news headlines often focused on protests and refusals. Yet early anecdotal evidence suggests some mandates have helped. For instance, after New York City public schools announced a vaccine requirement in late August for its roughly 150,000 employees, nearly 96 percent had received at least one shot by early November. Still, about 8,000 employees opted not to get vaccinated and were placed on unpaid leave, the New York Times reported.

Many people remain vehemently opposed to the vaccines, in part because of rampant misinformation that can spread quickly online. Whether more mandates, from the government or private companies, and targeted outreach will convince them remains to be seen. — Jonathan Lambert

Vaccines can’t single-handedly end the pandemic
One year in, it’s clear that vaccination is one of the best tools we have to control COVID-19. But it’s also clear vaccines alone can’t end the pandemic.

While the jabs do a pretty good job preventing infections, that protection wanes over time (SN Online: 3/30/21). Still, the vaccines have “worked spectacularly well” at protecting most people from severe disease, says Luning Prak, the University of Pennsylvania immunologist. And as more people around the world get vaccinated, fewer people will die, even if they do fall ill with COVID-19.

“We have to make a distinction between the superficial infections you can get — [like a] runny nose — versus the lower respiratory tract stuff that can kill you,” such as inflammation in the lungs that causes low oxygen levels, Luning Prak says. Preventing severe disease is the fundamental target that most vaccines, including the flu shot, hit, she notes. Stopping infection entirely “was never a realistic goal.”
Because vaccines aren’t an impenetrable barrier against the virus, we’ll still need to rely on other tactics to help control spread amid the pandemic. “Vaccines are not the sole tool in our toolbox,” says Saad Omer, an epidemiologist at Yale University. “They should be used with other things,” such as masks to help block exposure and COVID-19 tests to help people know when they should stay home.

For now, it’s crucial to have such layered protection, Omer says. “But in the long run, I think vaccines provide a way to get back to at least a new normal.” With vaccines, people can gather at school, concerts or weddings with less fear of a large outbreak.

Eventually the pandemic will end, though when is still anyone’s guess. But the end certainly won’t mean that COVID-19 has disappeared.

Many experts agree that the coronavirus will most likely remain with us for the foreseeable future, sparking outbreaks in places where there are pockets of susceptible people. Susceptibility can come in many forms: Young children who have never encountered the virus before and can’t yet get vaccinated, people who choose not to get the vaccine and people whose immunity has waned after an infection or vaccination. Or the virus may evolve in ways that help it evade the immune system.

The pandemic’s end may still feel out of reach, with the high hopes from the beginning of 2021 a distant memory. Still, hints of normalcy have returned: Kids are back in school, restaurants and stores are open and people are traveling more.

Vaccines have proved to be an invaluable tool to reduce the death and destruction that the coronavirus can leave in its wake. — Erin Garcia de Jesús

‘The Dawn of Everything’ rewrites 40,000 years of human history

Concerns abound about what’s gone wrong in modern societies. Many scholars explain growing gaps between the haves and the have-nots as partly a by-product of living in dense, urban populations. The bigger the crowd, from this perspective, the more we need power brokers to run the show. Societies have scaled up for thousands of years, which has magnified the distance between the wealthy and those left wanting.

In The Dawn of Everything, anthropologist David Graeber and archaeologist David Wengrow challenge the assumption that bigger societies inevitably produce a range of inequalities. Using examples from past societies, the pair also rejects the popular idea that social evolution occurred in stages.

Such stages, according to conventional wisdom, began with humans living in small hunter-gatherer bands where everyone was on equal footing. Then an agricultural revolution about 12,000 years ago fueled population growth and the emergence of tribes, then chiefdoms and eventually bureaucratic states. Or perhaps murderous alpha males dominated ancient hunter-gatherer groups. If so, early states may have represented attempts to corral our selfish, violent natures.

Neither scenario makes sense to Graeber and Wengrow. Their research synthesis — which extends for 526 pages — paints a more hopeful picture of social life over the last 30,000 to 40,000 years. For most of that time, the authors argue, humans have tactically alternated between small and large social setups. Some social systems featured ruling elites, working stiffs and enslaved people. Others emphasized decentralized, collective decision making. Some were run by men, others by women. The big question — one the authors can’t yet answer — is why, after tens of thousands of years of social flexibility, many people today can’t conceive of how society might effectively be reorganized.
Hunter-gatherers have a long history of revamping social systems from one season to the next, the authors write. About a century ago, researchers observed that Indigenous populations in North America and elsewhere often operated in small, mobile groups for part of the year and crystallized into large, sedentary communities the rest of the year. For example, each winter, Canada’s Northwest Coast Kwakiutl hunter-gatherers built wooden structures where nobles ruled over designated commoners and enslaved people, and held banquets called potlatch. In summers, aristocratic courts disbanded, and clans with less formal social ranks fished along the coast.

Many Late Stone Age hunter-gatherers similarly assembled and dismantled social systems on a seasonal basis, evidence gathered over the last few decades suggests. Scattered discoveries of elaborate graves for apparently esteemed individuals (SN: 10/5/17) and huge structures made of stone (SN: 2/11/21), mammoth bones and other material dot Eurasian landscapes. The graves may hold individuals who were accorded special status, at least at times of the year when mobile groups formed large communities and built large structures, the authors speculate. Seasonal gatherings to conduct rituals and feasts probably occurred at the monumental sites. No signs of centralized power, such as palaces or storehouses, accompany those sites.

Social flexibility and experimentation, rather than a revolutionary shift, also characterized ancient transitions to agriculture, Graeber and Wengrow write. Middle Eastern village excavations now indicate that the domestication of cereals and other crops occurred in fits and starts from around 12,000 to 9,000 years ago. Ancient Fertile Crescent communities periodically gave farming a go while still hunting, foraging, fishing and trading. Early cultivators were in no rush to treat tracts of land as private property or to form political systems headed by kings, the authors conclude.

Even in early cities of Mesopotamia and Eurasia around 6,000 years ago (SN: 2/19/20), absolute rule by monarchs did not exist. Collective decisions were made by district councils and citizen assemblies, archaeological evidence suggests. In contrast, authoritarian, violent political systems appeared in the region’s mobile, nonagricultural populations at that time.

Early states formed in piecemeal fashion, the authors argue. These political systems incorporated one or more of three basic elements of domination: violent control of the masses by authorities, bureaucratic management of special knowledge and information, and public demonstrations of rulers’ power and charisma. Egypt’s early rulers more than 4,000 years ago fused violent coercion of their subjects with extensive bureaucratic controls over daily affairs. Classic Maya rulers in Central America 1,100 years ago or more relied on administrators to monitor cosmic events while grounding earthly power in violent control and alliances with other kings.

States can take many forms, though. Graeber and Wengrow point to Bronze Age Minoan society on Crete as an example of a political system run by priestesses who called on citizens to transcend individuality via ecstatic experiences that bound the population together.

What seems to have changed today is that basic social liberties have receded, the authors contend. The freedom to relocate to new kinds of communities, to disobey commands issued by others and to create new social systems or alternate between different ones has become a scarce commodity. Finding ways to reclaim that freedom is a major challenge.

These examples give just a taste of the geographic and historical ground covered by the authors. Shortly after finishing writing the book, Graeber, who died in 2020, tweeted: “My brain feels bruised with numb surprise.” That sense of revelation animates this provocative take on humankind’s social journey.

When James Webb launches, it will have a bigger to-do list than 1980s researchers suspected

he James Webb Space Telescope has been a long time coming. When it launches later this year, the observatory will be the largest and most complex telescope ever sent into orbit. Scientists have been drafting and redrafting their dreams and plans for this unique tool since 1989.

The mission was originally scheduled to launch between 2007 and 2011, but a series of budget and technical issues pushed its start date back more than a decade. Remarkably, the core design of the telescope hasn’t changed much. But the science that it can dig into has. In the years of waiting for Webb to be ready, big scientific questions have emerged. When Webb was an early glimmer in astronomers’ eyes, cosmological revolutions like the discoveries of dark energy and planets orbiting stars outside our solar system hadn’t yet happened.

“It’s been over 25 years,” says cosmologist Wendy Freedman of the University of Chicago. “But I think it was really worth the wait.”

An audacious plan
Webb has a distinctive design. Most space telescopes house a single lens or mirror within a tube that blocks sunlight from swamping the dim lights of the cosmos. But Webb’s massive 6.5-meter-wide mirror and its scientific instruments are exposed to the vacuum of space. A multilayered shield the size of a tennis court will block light from the sun, Earth and moon.

For the awkward shape to fit on a rocket, Webb will launch folded up, then unfurl itself in space (see below, What could go wrong?).

“They call this the origami satellite,” says astronomer Scott Friedman of the Space Telescope Science Institute, or STScI, in Baltimore. Friedman is in charge of Webb’s postlaunch choreography. “Webb is different from any other telescope that’s flown.”
Its basic design hasn’t changed in more than 25 years. The telescope was first proposed in September 1989 at a workshop held at STScI, which also runs the Hubble Space Telescope.

At the time, Hubble was less than a year from launching, and was expected to function for only 15 years. Thirty-one years after its launch, the telescope is still going strong, despite a series of computer glitches and gyroscope failures (SN Online: 10/10/18).

The institute director at the time, Riccardo Giacconi, was concerned that the next major mission would take longer than 15 years to get off the ground. So he and others proposed that NASA investigate a possible successor to Hubble: a space telescope with a 10-meter-wide primary mirror that was sensitive to light in infrared wavelengths to complement Hubble’s range of ultraviolet, visible and near-infrared.

Infrared light has a longer wavelength than light that is visible to human eyes. But it’s perfect for a telescope to look back in time. Because light travels at a fixed speed, looking at distant objects in the universe means seeing them as they looked in the past. The universe is expanding, so that light is stretched before it reaches our telescopes. For the most distant objects in the universe — the first galaxies to clump together, or the first stars to burn in those galaxies — light that was originally emitted in shorter wavelengths is stretched all the way to the infrared.

Giacconi and his collaborators dreamed of a telescope that would detect that stretched light from the earliest galaxies. When Hubble started sharing its views of the early universe, the dream solidified into a science plan. The galaxies Hubble saw at great distances “looked different from what people were expecting,” says astronomer Massimo Stiavelli, a leader of the James Webb Space Telescope project who has been at STScI since 1995. “People started thinking that there is interesting science here.”

In 1995, STScI and NASA commissioned a report to design Hubble’s successor. The report, led by astronomer Alan Dressler of the Carnegie Observatories in Pasadena, Calif., suggested an infrared space observatory with a 4-meter-wide mirror.

The bigger a telescope’s mirror, the more light it can collect, and the farther it can see. Four meters wasn’t that much larger than Hubble’s 2.4-meter-wide mirror, but anything bigger would be difficult to launch.

Dressler briefed then-NASA Administrator Dan Goldin in late 1995. In January 1996 at the American Astronomical Society’s annual meeting, Goldin challenged the scientists to be more ambitious. He called out Dressler by name, saying, “Why do you ask for such a modest thing? Why not go after six or seven meters?” (Still nowhere near Giacconi’s pie-in-the-sky 10-meter wish.) The speech received a standing ovation.

Six meters was a larger mirror than had ever flown in space, and larger than would fit in available launch vehicles. Scientists would have to design a telescope mirror that could fold, then deploy once it reached space.

The telescope would also need to cool itself passively by radiating heat into space. It needed a sun shield — a big one. The origami telescope was born. It was dubbed James Webb in 2002 for NASA’s administrator from 1961 to 1968, who fought to support research to boost understanding of the universe in the increasingly human-focused space program. (In response to a May petition to change the name, NASA investigated allegations that James Webb persecuted gay and lesbian people during his government career. The agency announced on September 27 that it found no evidence warranting a name change.)
Goldin’s motto at NASA was “Faster, better, cheaper.” Bigger was better for Webb, but it sure wasn’t faster — or cheaper. By late 2010, the project was more than $1.4 billion over its $5.1 billion budget (SN: 4/9/11, p. 22). And it was going to take another five years to be ready. Today, the cost is estimated at almost $10 billion.

The telescope survived a near-cancellation by Congress, and its timeline was reset for an October 2018 launch. But in 2017, the launch was pushed to June 2019. Two more delays in 2018 pushed the takeoff to May 2020, then to March 2021. Some of those delays were because assembling and testing the spacecraft took longer than NASA expected.

Other slowdowns were because of human errors, like using the wrong cleaning solvent, which damaged valves in the propulsion system. Recent shutdowns due to the coronavirus pandemic pushed the launch back a few more months.

“I don’t think we ever imagined it would be this long,” says University of Chicago’s Freedman, who worked on the Dressler report. But there’s one silver lining: Science marched on.

The age conflict
The first science goal listed in the Dressler report was “the detailed study of the birth and evolution of normal galaxies such as the Milky Way.” That is still the dream, partly because it’s such an ambitious goal, Stiavelli says.

“We wanted a science rationale that would resist the test of time,” he says. “We didn’t want to build a mission that would do something that gets done in some other way before you’re done.”

Webb will peek at galaxies and stars as they were just 400 million years after the Big Bang, which astronomers think is the epoch when the first tiny galaxies began making the universe transparent to light by stripping electrons from cosmic hydrogen.

But in the 1990s, astronomers had a problem: There didn’t seem to be enough time in the universe to make galaxies much earlier than the ones astronomers had already seen. The standard cosmology at the time suggested the universe was 8 billion or 9 billion years old, but there were stars in the Milky Way that seemed to be about 14 billion years old.

“There was this age conflict that reared its head,” Freedman says. “You can’t have a universe that’s younger than the oldest stars. The way people put it was, ‘You can’t be older than your grandmother!’”
In 1998, two teams of cosmologists showed that the universe is expanding at an ever-increasing rate. A mysterious substance dubbed dark energy may be pushing the universe to expand faster and faster. That accelerated expansion means the universe is older than astronomers previously thought — the current estimate is about 13.8 billion years old.

“That resolved the age conflict,” Freedman says. “The discovery of dark energy changed everything.” And it expanded Webb’s to-do list.

Dark energy
Top of the list is getting to the bottom of a mismatch in cosmic measurements. Since at least 2014, different methods for measuring the universe’s rate of expansion — called the Hubble constant — have been giving different answers. Freedman calls the issue “the most important problem in cosmology today.”

The question, Freedman says, is whether the mismatch is real. A real mismatch could indicate something profound about the nature of dark energy and the history of the universe. But the discrepancy could just be due to measurement errors.

Webb can help settle the debate. One common way to determine the Hubble constant is by measuring the distances and speeds of far-off galaxies. Measuring cosmic distances is difficult, but astronomers can estimate them using objects of known brightness, called standard candles. If you know the object’s actual brightness, you can calculate its distance based on how bright it seems from Earth.

Studies using supernovas and variable stars called Cepheids as candles have found an expansion rate of 74.0 kilometers per second for approximately every 3 million light-years, or megaparsec, of distance between objects. But using red giant stars, Freedman and colleagues have gotten a smaller answer: 69.8 km/s/Mpc.

Other studies have measured the Hubble constant by looking at the dim glow of light emitted just 380,000 years after the Big Bang, called the cosmic microwave background. Calculations based on that glow give a smaller rate still: 67.4 km/s/Mpc. Although these numbers may seem close, the fact that they disagree at all could alter our understanding of the contents of the universe and how it evolves over time. The discrepancy has been called a crisis in cosmology (SN: 9/14/19, p. 22).

In its first year, Webb will observe some of the same galaxies used in the supernova studies, using three different objects as candles: Cepheids, red giants and peculiar stars called carbon stars.

The telescope will also try to measure the Hubble constant using a distant gravitationally lensed galaxy. Comparing those measurements with each other and with similar ones from Hubble will show if earlier measurements were just wrong, or if the tension between measurements is real, Freedman says.

Without these new observations, “we were just going to argue about the same things forever,” she says. “We just need better data. And [Webb] is poised to deliver it.”
Exoplanets
Perhaps the biggest change for Webb science has been the rise of the field of exoplanet explorations.

“When this was proposed, exoplanets were scarcely a thing,” says STScI’s Friedman. “And now, of course, it’s one of the hottest topics in all of science, especially all of astronomy.”

The Dressler report’s second major goal for Hubble’s successor was “the detection of Earthlike planets around other stars and the search for evidence of life on them.” But back in 1995, only a handful of planets orbiting other sunlike stars were even known, and all of them were scorching-hot gas giants — nothing like Earth at all.

Since then, astronomers have discovered thousands of exoplanets orbiting distant stars. Scientists now estimate that, on average, there is at least one planet for every star we see in the sky. And some of the planets are small and rocky, with the right temperatures to support liquid water, and maybe life.

Most of the known planets were discovered as they crossed, or transited, in front of their parent stars, blocking a little bit of the parent star’s light. Astronomers soon realized that, if those planets have atmospheres, a sensitive telescope could effectively sniff the air by examining the starlight that filters through the atmosphere.

The infrared Spitzer Space Telescope, which launched in 2003, and Hubble have started this work. But Spitzer ran out of coolant in 2009, keeping it too warm to measure important molecules in exoplanet atmospheres. And Hubble is not sensitive to some of the most interesting wavelengths of light — the ones that could reveal alien life-forms.

That’s where Webb is going to shine. If Hubble is peeking through a crack in a door, Webb will throw the door wide open, says exoplanet scientist Nikole Lewis of Cornell University. Crucially, Webb, unlike Hubble, will be particularly sensitive to several carbon-bearing molecules in exoplanet atmospheres that might be signs of life.

“Hubble can’t tell us anything really about carbon, carbon monoxide, carbon dioxide, methane,” she says.

If Webb had launched in 2007, it could have missed this whole field. Even though the first transiting exoplanet was discovered in 1999, their numbers were low for the next decade.

Lewis remembers thinking, when she started grad school in 2007, that she could make a computer model of all the transiting exoplanets. “Because there were literally only 25,” she says.
Between 2009 and 2018, NASA’s Kepler space telescope raked in transiting planets by the thousands. But those planets were too dim and distant for Webb to probe their atmospheres.

So the down-to-the-wire delays of the last few years have actually been good for exoplanet research, Lewis says. “The launch delays were one of the best things that’s happened for exoplanet science with Webb,” she says. “Full stop.”

That’s mainly thanks to NASA’s Transiting Exoplanet Survey Satellite, or TESS, which launched in April 2018. TESS’ job is to find planets orbiting the brightest, nearest stars, which will give Webb the best shot at detecting interesting molecules in planetary atmospheres.

If it had launched in 2018, Webb would have had to wait a few years for TESS to pick out the best targets. Now, it can get started on those worlds right away. Webb’s first year of observations will include probing several known exoplanets that have been hailed as possible places to find life. Scientists will survey planets orbiting small, cool stars called M dwarfs to make sure such planets even have atmospheres, a question that has been hotly debated.

If a sign of life does show up on any of these planets, that result will be fiercely debated, too, Lewis says. “There will be a huge kerfuffle in the literature when that comes up.” It will be hard to compare planets orbiting M dwarfs with Earth, because these planets and their stars are so different from ours. Still, “let’s look and see what we find,” she says.

A limited lifetime
With its components assembled, tested and folded at Northrop Grumman’s facilities in California, Webb is on its way by boat through the Panama Canal, ready to launch in an Ariane 5 rocket from French Guiana. The most recent launch date is set for December 18.

For the scientists who have been working on Webb for decades, this is a nostalgic moment.

“You start to relate to the folks who built the pyramids,” Stiavelli says.

Other scientists, who grew up in a world where Webb was always on the horizon, are already thinking about the next big thing.

“I’m pretty sure, barring epic disaster, that [Webb] will carry my career through the next decade,” Lewis says. “But I have to think about what I’ll do in the next decade” after that.

Unlike Hubble, which has lasted decades thanks to fixes by astronauts and upgrade missions, Webb has a strictly limited lifetime. Orbiting the sun at a gravitationally fixed point called L2, Webb will be too far from Earth to repair, and will need to burn small amounts of fuel to stay in position. The fuel will last for at least five years, and hopefully as much as 10. But when the fuel runs out, Webb is finished. The telescope operators will move it into retirement in an out-of-the-way orbit around the sun, and bid it farewell.

Space rocks may have bounced off baby Earth, but slammed into Venus

Squabbling sibling planets may have hurled space rocks when they were young.

Simulations suggest that space rocks the size of baby planets struck both the newborn Earth and Venus, but many of the rocks that only grazed Earth went on to hit — and stick — to Venus. That difference in early impacts could help explain why Earth and Venus are such different worlds today, researchers report September 23 in the Planetary Science Journal.

“The pronounced differences between Earth and Venus, in spite of their similar orbits and masses, has been one of the biggest puzzles in our solar system,” says planetary scientist Shigeru Ida of the Tokyo Institute of Technology, who was not involved in the new work. This study introduces “a new point that has not been raised before.”

Scientists have typically thought that there are two ways that collisions between baby planets can go. The objects could graze each other and each continue on its way, in a hit-and-run collision. Or two protoplanets could stick together, or accrete, making one larger planet. Planetary scientists often assume that every hit-and-run collision eventually leads to accretion. Objects that collide must have orbits that cross each other’s, so they’re bound to collide again and again, and eventually should stick.
But previous work from planetary scientist Erik Asphaug of the University of Arizona in Tucson and others suggests that isn’t so. It takes special conditions for two planets to merge, Asphaug says, like relatively slow impact speeds, so hit-and-runs were probably much more common in the young solar system.

Asphaug and colleagues wondered what that might have meant for Earth and Venus, two apparently similar planets with vastly different climates. Both worlds are about the same size and mass, but Earth is wet and clement while Venus is a searing, acidic hellscape (SN: 2/13/18).

“If they started out on similar pathways, somehow Venus took a wrong turn,” Asphaug says.

The team ran about 4,000 computer simulations in which Mars-sized protoplanets crashed into a young Earth or Venus, assuming the two planets were at their current distances from the sun. The researchers found that about half of the time, incoming protoplanets grazed Earth without directly colliding. Of those, about half went on to collide with Venus.

Unlike Earth, Venus ended up accreting most of the objects that hit it in the simulations. Hitting Earth first slowed incoming objects down enough to let them stick to Venus later, the study suggests. “You have this imbalance where things that hit the Earth, but don’t stick, tend to end up on Venus,” Asphaug says. “We have a fundamental explanation for why Venus ended up accreting differently from the Earth.”

If that’s really what happened, it would have had a significant effect on the composition of the two worlds. Earth would have ended up with more of the outer mantle and crust material from the incoming protoplanets, while Venus would have gotten more of their iron-rich cores.

The imbalance in impacts could even explain some major Venusian mysteries, like why the planet doesn’t have a moon, why it spins so slowly and why it lacks a magnetic field — though “these are hand-waving kind of conjectures,” Asphaug says.

Ida says he hopes that future work will look into those questions more deeply. “I’m looking forward to follow-up studies to examine if the new result actually explains the Earth-Venus difference,” he says.

The idea fits into a growing debate among planetary scientists about how the solar system grew up, says planetary scientist Seth Jacobson of Michigan State University in East Lansing. Was it built violently, with lots of giant collisions, or calmly, with planets growing smoothly via pebbles sticking together?

“This paper falls on the end of lots of giant impacts,” Jacobson says.

Each rocky planet in the solar system should have very different chemistry and structure depending on which scenario is true. But scientists know the chemistry and structure of only one planet with any confidence: Earth. And Earth’s early history has been overwritten by plate tectonics and other geologic activity. “Venus is the missing link,” Jacobson says. “Learning more about Venus’ chemistry and interior structure is going to tell us more about whether it had a giant impact or not.”

Three missions to Venus are expected to launch in the late 2020s and 2030s (SN: 6/2/21). Those should help, but none are expected to take the kind of detailed composition measurements that could definitively solve the mystery. That would take a long-lived lander, or a sample return mission, both of which would be extremely difficult on hot, hostile Venus.

“I wish there was an easier way to test it,” Jacobson says. “I think that’s where we should concentrate our energy as terrestrial planet formation scientists going forward.”

NASA’s Perseverance rover snagged its first Martian rock samples

The Perseverance rover has captured its first two slices of Mars.

NASA’s latest Mars rover drilled into a flat rock nicknamed Rochette on September 1 and filled a roughly finger-sized tube with stone. The sample is the first ever destined to be sent back to Earth for further study. On September 7, the rover snagged a second sample from the same rock. Both are now stored in airtight tubes inside the rover’s body.

Getting pairs of samples from every rock it drills is “a little bit of an insurance policy,” says deputy project scientist Katie Stack Morgan of NASA’s Jet Propulsion Lab in Pasadena, Calif. It means the rover can drop identical stores of samples in two different places, boosting chances that a future mission will be able to pick up at least one set.

The successful drilling is a comeback story for Perseverance. The rover’s first attempt to take a bit of Mars ended with the sample crumbling to dust, leaving an empty tube (SN: 8/19/21). Scientists think that rock was too soft to hold up to the drill.
Nevertheless, the rover persevered.

“Even though some of its rocks are not, Mars is hard,” said Lori Glaze, director of NASA’s planetary science division, in a September 10 news briefing.

Rochette is a hard rock that appears to have been less severely eroded by millennia of Martian weather (SN: 7/14/20). (Fun fact: All the rocks Perseverance drills into will get names related to national parks; the region on Mars the rover is now exploring is called Mercantour, so the name Rochette — or “Little Rock” — comes from a village in France near Mercantour National Park.)

Rover measurements of the rock’s texture and chemistry suggests that it’s made of basalt and may have been part of an ancient lava flow. That’s useful because volcanic rocks preserve their ages well, Stack Morgan says. When scientists on Earth get their hands on the sample, they’ll be able to use the concentrations of certain elements and isotopes to figure out exactly how old the rock is — something that’s never been done for a pristine Martian rock.

Rochette also contains salt minerals that probably formed when the rock interacted with water over long time periods. That could suggest groundwater moving through the Martian subsurface, maybe creating habitable environments within the rocks, Stack Morgan says.

“It really feels like this rich treasure trove of information for when we get this sample back,” Stack Morgan says.

Once a future mission brings the rocks back to Earth, scientists can search inside those salts for tiny fluid bubbles that might be trapped there. “That would give us a glimpse of Jezero crater at the time when it was wet and was able to sustain ancient Martian life,” said planetary scientist Yulia Goreva of JPL at the news briefing.

Scientists will have to be patient, though — the earliest any samples will make it back to Earth is 2031. But it’s still a historic milestone, says planetary scientist Meenakshi Wadhwa of Arizona State University in Tempe.

“These represent the beginning of Mars sample return,” said Wadhwa said at the news briefing. “I’ve dreamed of having samples back from Mars to analyze in my lab since I was a graduate student. We’ve talked about Mars sample return for decades. Now it’s starting to actually feel real.”

Astronomers may have seen a star gulp down a black hole and explode

For the first time, astronomers have captured solid evidence of a rare double cosmic cannibalism — a star swallowing a compact object such as a black hole or neutron star. In turn, that object gobbled the star’s core, causing it to explode and leave behind only a black hole.

The first hints of the gruesome event, described in the Sept. 3 Science, came from the Very Large Array (VLA), a radio telescope consisting of 27 enormous dishes in the New Mexican desert near Socorro. During the observatory’s scans of the night sky in 2017, a burst of radio energy as bright as the brightest exploding star — or supernova — as seen from Earth appeared in a dwarf star–forming galaxy approximately 500 million light-years away.

“We thought, ‘Whoa, this is interesting,’” says Dillon Dong, an astronomer at Caltech.

He and his colleagues made follow-up observations of the galaxy using the VLA and one of the telescopes at the W.M. Keck Observatory in Hawaii, which sees in the same optical light as our eyes. The Keck telescope caught a luminous outflow of material spewing in all directions at 3.2 million kilometers per hour from a central location, suggesting that an energetic explosion had occurred there in the past.
The team then found an extremely bright X-ray source in archival data from the Monitor of All Sky X-ray Image (MAXI) telescope, a Japanese instrument that sits on the International Space Station. This X-ray burst was in the same place as the radio one but had been observed back in 2014.

Piecing the data together, Dong and his colleagues think this is what happened: Long ago, a binary pair of stars were born orbiting each other; one died in a spectacular supernova and became either a neutron star or a black hole. As gravity brought the two objects closer together, the dead star actually entered the outer layers of its larger stellar sibling.

The compact object spiraled inside the still-living star for hundreds of years, eventually making its way down to and then eating its partner’s core. During this time, the larger star shed huge amounts of gas and dust, forming a shell of material around the duo.

In the living star’s center, gravitational forces and complex magnetic interactions from the dead star’s munching launched enormous jets of energy — picked up as an X-ray flash in 2014 — as well as causing the larger star to explode. Debris from the detonation smashed with colossal speed into the surrounding shell of material, generating the optical and radio light.

While theorists have previously envisioned such a scenario, dubbed a merger-triggered core collapse supernova, this appears to represent the first direct observation of this phenomenon, Dong says.

“They’ve done some pretty good detective work using these observations,” says Adam Burrows, an astrophysicist at Princeton University who was not involved in the new study. He says the findings should help constrain the timing of a process called common envelope evolution, in which one star becomes immersed inside another. Such stages in stars’ lives are relatively short-lived in cosmic time and difficult to both observe and simulate. Most of the time, the engulfing partner dies before its core is consumed, leading to two compact objects like white dwarfs, neutron stars or black holes orbiting one another.

The final stages of these systems are exactly what observatories like the Advanced Laser Interferometer Gravitational-Wave Observatory, or LIGO, detect when capturing spacetime’s ripples, Dong says (SN: 8/4/21). Now that astronomers know to look for these multiple lines of evidence, he expects them to find more examples of this strange phenomenon.

UEFA Champions League draw: Date, teams qualified, seeds, rules for Round of 16

The complete field of 16 teams that will advance to the 2021-22 UEFA Champions League knockout rounds has not yet been finalized, but we already have several clubs that have booked their spots.

European giants Liverpool, Ajax, Bayern Munich and Juventus were the first four teams to clinch on Matchday 4 of the group stage, while Manchester United and Chelsea joined them on Matchday 5.
Only the top two teams in each group advance, and there's incentive to win the group when it comes to the Round of 16 draw on Monday, Dec. 13. The first-place team from each group will be seeded, and their Round of 16 opponent will be drawn from a pot of the second-place finishers.

Champions League Round of 16 qualifiers
Group 1st Place 2nd Place
Grp A — —
Grp B Liverpool —
Grp C Ajax —
Grp D — —
Grp E Bayern Munich —
Grp F Manchester United —
Grp G — —
Grp H Chelsea / Juventus Chelsea / Juventus
When is the Champions League Round of 16 draw?
The Round of 16 draw will be held on Dec. 13 at 6 a.m. ET from the UEFA headquarters in Switzerland. It will be streamed by UEFA.com.

The eight group winners will be seeded for purposes of the draw. They will make up one pot, while the other pot will contain the runners-up from each group.

The two key details to remember for this Round of 16 draw:

Teams from the same country cannot be drawn against one another (see table below);
The group winners (i.e. seeded teams) will host the second leg of each Round of 16 series. This is perceived to be an advantage because, if an extra-time session or penalty-kick shootout is needed, it would happen on home soil.
Knockout round qualifiers by country
Nation Total Clubs Clubs
England 3 Chelsea, Liverpool, Manchester United
Germany 1 Bayern Munich
Italy 1 Juventus
Netherlands 1 Ajax Amsterdam
The two legs of the Round of 16 will be spread over eight days between February and March. The second leg of each series will take place three weeks after the first leg.

The eight teams left standing will participate in a quarterfinal draw on March 18, 2022, which will determine the rest of the Champions League bracket through the final in Saint Petersburg on May 28. There are no seedings involved in this draw, and unlike the Round of 16, teams from the same country can be drawn against one another.

Champions League Round of 16 schedule
Round of 16, 1st Legs
Date Match Time (ET) TV channels Stream
Feb. 15 Round of 16 #1 3 p.m. TBD fuboTV, Paramount+
Feb. 15 Round of 16 #2 3 p.m. TBD fuboTV, Paramount+
Feb. 16 Round of 16 #3 3 p.m. TBD fuboTV, Paramount+
Feb. 16 Round of 16 #4 3 p.m. TBD fuboTV, Paramount+
Feb. 22 Round of 16 #5 3 p.m. TBD fuboTV, Paramount+
Feb. 22 Round of 16 #6 3 p.m. TBD fuboTV, Paramount+
Feb. 23 Round of 16 #7 3 p.m. TBD fuboTV, Paramount+
Feb. 23 Round of 16 #8 3 p.m. TBD fuboTV, Paramount+
Round of 16, 2nd Legs
Date Match Time (ET) TV channels Stream
March 8 Round of 16 #1 3 p.m. TBD fuboTV, Paramount+
March 8 Round of 16 #2 3 p.m. TBD fuboTV, Paramount+
March 9 Round of 16 #3 3 p.m. TBD fuboTV, Paramount+
March 9 Round of 16 #4 3 p.m. TBD fuboTV, Paramount+
March 15 Round of 16 #5 3 p.m. TBD fuboTV, Paramount+
March 15 Round of 16 #6 3 p.m. TBD fuboTV, Paramount+
March 16 Round of 16 #7 3 p.m. TBD fuboTV, Paramount+
March 16 Round of 16 #8 3 p.m. TBD fuboTV, Paramount+
Who will win the UEFA Champions League 2021-22?
As the tournament progresses, the oddsmakers are constantly adjusting the future prices for each team when it comes to winning the Champions League. Here are the latests odds courtesy of U.S.-based DraftKings (asterisk denotes teams that have already qualified for the Round of 16):

Champions League outright winner odds
Team Nov. 23
Manchester City +300
Bayern Munich* +350
PSG +500
Liverpool* +550
Chelsea* +600
Manchester United* +1200
Ajax* +2000
Real Madrid +2200
Atletico Madrid +3500
Juventus* +3500
Inter Milan +5000
B. Dortmund +5000
Barcelona +5000
Atalanta +10000
Porto +15000
Benfica +15000
Villarreal +15000
RB Salzburg +15000
Sevilla +20000
Wolfsburg +30000
Lille +50000
Club Brugge +80000
Sporting CP +100000
UEFA Champions League 2021-2022: Tournament format
The 2021-2022 edition of the UEFA Champions League features a familiar format — and one massive new twist.

As usual, the tournament started out with a group stage (eight groups of four teams each), and only the top two finishers in each group advance to the Round of 16 that kicks off in February 2022. Two-leg, aggregate-goal knockout rounds are played the rest of the way through to the single game final that will be held in Russia on May 28, 2022.

Group Stage: Sept. 14-15, Sept. 28-29, Oct. 19-20, Nov. 2-3, Nov. 23-24, Dec. 7-8
Round of 16: Feb. 15-16, March 8-9 / Feb. 22-23, March 15-16
Quarterfinals: April 5-6, April 12-13
Semifinals: April 26-27, May 3-4
Final: May 28, 2022 (St. Petersburg, Russia)
No away goals tiebreaker in Champions League
Here's that twist: For the first time since 1965, there will be no away goals tiebreaker used in the knockout rounds of UEFA competitions, including the Champions League, after it was abolished in June 2021.

Series that are tied on aggregate goals after the conclusion of the second leg will go straight to extra time and, if necessary, a penalty-kick shootout.

How to watch the UEFA Champions League
The 2021-22 UEFA Champions League will be carried in the United States by CBS (English) and Univision (Spanish) across a number of TV and streaming platforms.

CBS Sports will have live pregame, halftime and postgame studio shows, which will air on CBS Sports Network and stream on Paramount+. Also back this year is the RedZone-like whip-around show called "The Golazo Show," also on CBS Sports Network and Paramount+, with all the goals and best chances from the concurrent matches.

Univision will mirror that coverage with its own pregame and postgame shows. Its whip-around show is called "Zona Fútbol."

Nearly every Champions League match is available to be streamed on fuboTV, which offers a free seven-day trial to new subscribers. The streaming platform carries all the Univision family of channels: Univision, TUDN, UniMas, Galavision and TUDNxtra.

Univision will stream select matches on its ad-supported platform PrendeTV, which is available free of charge across mobile and connected TV devices, Amazon Fire TV, Apple (iOS and tvOS), Google (Android phones and TV devices), Roku, and via the web on Prende.tv.

Fantasy QB Rankings Week 12: Who to start, sit at quarterback in fantasy football

Those who spent up on Patrick Mahomes and Kyler Murray will be without their studs as the Chiefs and Cardinals take the week off. Of course, Murray owners are used to that, but hopefully that will change after his bye. This week also features three Thursday games, so your start 'em, sit 'emi decisions will feel a little more rushed. Winning the week starts with deciding who to start at quarterback, and our Week 12 fantasy QB rankings can help you makes those tough start 'em, sit 'em decisions.

We mentioned Murray and Mahomes are out, but season-long stud Matthew Stafford (@ Packers) and popular streaming option Teddy Bridgewater (vs. Chargers) are back in action after their byes. For those Mahomes and Murray owners, we'll admit it's not a very deep week for streamers, but there are just enough options to get by. Again, Murray owners are used to this routine, so they should have a decent backup. 

Stafford, along with Aaron Rodgers (vs. Rams), Justin Herbert (@ Broncos), and Joe Burrow (vs. Steelers), headline the "studs with tough matchups" category, but again, it's not the greatest week for streamers, so they all remain QB1s in our rankings.
The best streamers include Mac Jones (vs. Titans), Cam Newton (@ Dolphins), Trevor Lawrence (vs. Falcons), and Justin Fields (@ Lions). Matt Ryan (@ Jaguars) is over 50-percent owned, but if you consider him a streamer, he's in play, too. Those QBs either play teams that are downright awful against the pass statistically or bottom-dwellers that haven't forced many pass-happy game scripts. So, yes, we're counting on three rookies, a guy who was just signed off the street a few weeks ago, and a boom-or-bust veteran. What else did you expect at this point in the season? Also, he's not a streamer at this point either, but start Carson Wentz (vs. Buccaneers). The matchup and game script should set him up for a nice fantasy day.

On the other side of the start-or-sit bubble, we're out on Ryan Tannehill (@ Patriots), Daniel Jones (vs. Eagles), Tua Tagovailoa (@ Panthers), and Teddy Bridgewater (vs. Chargers). These guys have been mentioned several times by us on the "start" side of the conversation, but the matchups just aren't favorable enough to tout them as viable considerations this week. They're looking at some top defenses against fantasy QBs, so we'd opt to play the guys listed above. If you're forced to start one of the three, Jones has the highest upside because of his rushing ability.

This week isn't quite as disastrous of a week as we thought it could be in the preseason, so you can survive. This is the last week with two elite fantasy QBs out of commission, so there should be less competition for streamers going forward. Still, you have to stay on top of everything. We saw last Sunday with Lamar Jackson's surprise scratch that injuries and illnesses can strike with little warning, so always have a plan going into a week.

Note: We'll be updating these QB rankings throughout the week, so check back for the latest player movement and analysis.

Fantasy QB Rankings Week 12: Who to start at quarterback
Rankings are based on standard, four-point passing TD formats.

Rank Player
1 Russell Wilson, SEA @ WAS
2 Josh Allen, BUF @ NO
3 Tom Brady, TB @ IND
4 Lamar Jackson, BAL vs. CLE
5 Dak Prescott, DAL vs. LV
6 Jalen Hurts, PHI @ NYG
7 Matthew Stafford, LAR @ GB
8 Aaron Rodgers, GB vs. LAR
9 Carson Wentz, IND vs. TB
10 Joe Burrow, CIN vs. PIT
11 Justin Herbert, LAC @ DEN
12 Mac Jones, NE vs. TEN
13 Derek Carr, LV @ DAL
14 Cam Newton, CAR @ MIA
15 Kirk Cousins, MIN @ SF
16 Matt Ryan, ATL @ JAX
17 Tyrod Taylor, HOU vs. NYJ
18 Trevor Lawrence, JAX vs. ATL
19 Justin Fields, CHI @ DET
20 Daniel Jones, NYG vs. PHI
21 Jimmy Garoppolo, SF vs. MIN
22 Ryan Tannehill, TEN @ NE
23 Tua Tagovailoa, MIA vs. CAR
24 Teddy Bridgewater, DEN vs. LAC
25 Taylor Heinicke, WAS vs. SEA
26 Baker Mayfield, CLE @ BAL
27 Joe Flacco, NYJ @ HOU
28 Ben Roethlisberger, PIT @ CIN
29 Trevor Siemian, NO vs. BUF
30 Tim Boyle, DET vs. CHI

Terence Crawford vs. Shawn Porter results: Crawford retains WBO welterweight title with 10th-round stoppage

LAS VEGAS — All the questions about Terence Crawford have been answered.

For years, the only knock on him was that he lacked a signature victory. He finally picked up one — and in exceptional fashion — when he became the first fighter to stop Shawn Porter, recording a 10th-round TKO to retain his WBO welterweight championship in front of 11,568 fans at Michelob ULTRA Arena.
Now, the world will be clamoring for a unification bout with IBF and WBC champion Errol Spence Jr.

As it always has been against Porter, winning didn't come easy.

At the time of the stoppage, Crawford was up on all three scorecards: 86-85, 86-85 and 87-84. Porter routinely barreled inside and kept Crawford off balance with aggression and pressure. But Crawford began to time Porter's advances and then picked him off with counters that eventually wore down the former two-time champion.

In the 10th round, Crawford opened with a thudding left hand that deposited Porter on his backside. A frustrated Porter made it to his feet but was met with a scintillating combination that dropped Porter to his knees. Porter pounded on the canvas out of frustration and made it back to his feet again. Unfortunately, his father and trainer, Kenny Porter, decided that his son had had enough and threw in the towel.

Crawford improved to 38-0 with 29 knockouts. Porter became his ninth consecutive knockout victim. As for Porter, his career is at a crossroads of sorts as he falls to 31-4-1 and goes to the back of the line when it comes to title opportunities.

Here's how it all went down in Las Vegas.

Terence Crawford vs. Shawn Porter live updates, highlights
(All times Eastern.)

Round 10 (12:15 a.m.): Crawford drops Porter with a left hand to open the round! Porter is up and Crawford is a killer. He’s looking to finish the job. Crawford with a barrage that drops Crawford. Porter beats the canvas on his way up. Porter’s corner stops it! Wow!

Round 9 (12:13 a.m.): Short left hand by Porter lands to open the round. Big hook by Porter barely lands. Bud is unbothered. Body shot by Porter. Crawford looking for his spots and Porter isn’t making it easy. Crawford lands an uppercut on the inside and a body shot. 10-9, Crawford (86-85, Crawford)

Round 8 (12:09 a.m.): Crawford with a hard right hand and Porter comes straight at him throwing bombs. Crawford avoids and picks him off with a right hand. Beautiful sequence by Bud. Porter chops him on the inside with a short left and barrels inside. Hard left hand by Porter. Big right hand by Porter rattles Crawford. Crawford smiles and centers himself. How do you score this round? 10-9, Crawford (76-76)

Round 7 (12:04 a.m.): Porter strafes Bud with a left hand. Crawford gives Porter different looks and feints. They exchange left hands. Right hand by Porter lands and Crawford bounces off the ropes. Short counter right by Crawford as Porter rolls in. Porter won’t stop coming. Bud is smiling again. But he’s not throwing enough. 10-9, Porter (67-66, Porter)

Round 6 (12:01 a.m.): Crawford lands a big right hand They are going to war again. Crawford looking for the big shot and loading up. Porter comes roaring back. They clash heads. Crawford looks like he’s enjoying the dog fight. Porter roughs him up on the inside. Man, this is a damn fight. Counter left on the inside by Crawford. Lots of infighting to close a tight round. 10-9, Crawford (57-57)

Round 5 (11:57 p.m.): Porter working on Bud from the inside with some roughhousing. Crawford trying to walk Porter down. Flashes the jab. Porter bombing away on Crawford as he covers up. Not a lot gets through. Crawford walking him down. Porter is just outworking him in this round but Crawford is hoping he spent up his gas tank. 10-9, Porter (48-47, Porter)

Round 4 (11:52 p.m.): Hard left hook from Porter to open the round. Crawford lands a combination and a left hand. They exchange hard shots. Porter lands a right hand and Bud smiles. Porter with a jab and Bud responds to the body. Porter with a lunging hook that lands. Crawford with a check hook that almost Ricky Hatton'd Porter. They start swinging again. Closer round. 10-9, Crawford (38-38)

Round 3 (11:48 p.m): Crawford looks comfortable fighting lefty. Starts pushing Porter back. Porter lands a hard combination. Crawford tried to time and barely missed a counter hook. Porter stuns Bud with a left hand! Bud smiles but he was cracked. They are talking now. Porter is cut over the right eye. Crawford smiling but he knows that he's now in a fight. 10-9, Porter (29-28, Porter)

Round 2 (11:44 p.m.): Porter lands a jab and Bud switches to southpaw. Barely misses a counter. Lands a hard right hand on Porter. Porter cracks Bud with a hard right hand in response. Crawford lands a right hand and barely misses an uppercut. A firefight breaks out. Both landing hard shots. Bud with a counter uppercut and Porter with a right hand. Crawford lands the jab and smiles. We're about to have a good one. 10-9, Crawford (19-19)

Round 1 (11:40 p.m.): Porter rushes right at Crawford with a left hook and follows with a right hand that lands. Porter aims to rough Bud up along the ropes and gets tied up. Crawford is reading and timing Porter. Starts to fire the jab. Left hand by Porter lands. Hard jab by Bud lands. Crawford smirks at Porter. He may have figured out something already. 10-9, Porter

11:30 p.m.: "Showtime" Shawn Porter makes his entrance with WWE champion Big E and Grammy-nominated Hip Hop artist Rapsody while Terence Crawford keeps it simple by walking alone to LL Cool J's "I'm Bad."

10:58 p.m.: Through six rounds, Esquiva Falcao, the 2012 Olympic silver medalist from Brazil, has been applying immense pressure to Patrice Volny. Volny tried to work from the outside but Falcao's persistence to throttle Volny from the inside racked up rounds. But a nasty clash of heads in the sixth round split Falcao open above the left eye. Falcao is in a lot of pain and it's likely this fight is going to be stopped. Yup, it's over. Main event is next.

10:22 p.m.: Janibek Alimkhanuly didn't have much trouble turning back the challenge of Hassan N'Dam. He chopped him down over the course of eight rounds to earn the TKO stoppage. N'Dam's best years as a contender are clearly behind him, while Alimkhanuly remains one to watch in the middleweight division. As the rounds wore on, it became target practice for Alimkhanuly. N'Dam offered little resistance and was routinely clocked by power punches and a hard left hand. The mounting damage was too much for referee Kenny Bayless and the fight was called at the 2:40 mark of the eighth.

9:37 p.m.: As expected, Muratalia mowed down Araujo with an exceptional display of body punching and aggression to pick up the fifth-round TKO.

9 p.m.: We're live from Las Vegas and the pay-per-view portion of Crawford-Porter will kick off with Raymond Muratalla and Elias Araujo competing in a lightweight showdown.

Terence Crawford vs. Shawn Porter start time
Date: Saturday, Nov. 20
Main card time: 9 p.m. ET | 6 p.m. PT
Main event: 11 p.m. ET | 8 p.m. PT (approx.)
Crawford and Porter are set to step into the ring at about 11 p.m. ET. The night will begin with early prelims at 6 p.m. ET, followed by the prelim card at 7 p.m. ET and the main card at 9 p.m. ET.

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