New spacey stories: killer asteroids, stellar DNA, and rogue planets

I meant to post at least once a month, but I think you’ll understand that it’s hard to find the time while juggling new freelance science writing work with a 9-month-old kiddo at home. Anyway, here’s a couple pieces I’ve published over the past month. Enjoy! (See links below for the full articles.) As usual, thanks go to my helpful editors: Heather D’Angelo, Lisa Grossman, Lauren Morello and Jane Lee.


Maybe Dark Matter Didn’t Kill the Dinosaurs after All

Artist’s impression of the Chicxulub impact. Credit: Donald E. Davis, via Wikimedia Commons

A giant asteroid or comet the size of a city smashed into the Yucatán 66 million years ago, likely causing the demise of dinosaurs and many other species. Scientists have wondered: is that a random, unfortunate event, or has life on Earth been subjected to periodic impacts from outer space?

Some researchers proposed that, if the dinosaur extinction — the last of five mass extinctions — had an astronomical origin, rather than being driven by volcano eruptions or global warming, for example, then maybe others did too. And if impacts from huge boulders of rock and ice drove these extinctions, they had to come from somewhere. It’s possible that dark matter could periodically dislodge distant comets from their tenuous orbits beyond Pluto, sending a few of them dangerously in Earth’s direction — thus linking the fates of dark matter and dinosaurs.

But a new study by a team of physicists and geologists from Durham University and Lancaster University in the United Kingdom appears to shoot down that dark matter interpretation. If it were true, extinctions would have happened in cycles. But these scientists pored over the fossil record over the past 500 million years, looking for extinctions occurring periodically, but they didn’t find any significant patterns like that in the data.

“We needn’t search the heavens to find reasons for these extinction events. The vast majority of them are due to Earth processes, not astronomical ones,” says David Harper, lead author of the study.

The dark matter idea, popularized by Lisa Randall’s 2015 book, “Dark Matter and the Dinosaurs,” might sound far-fetched. But…

[Read the entire story in, published on 14 March 2017.]

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My new freelance writings: climate costs, light pollution, binary stars

I set out as a freelance science writer this month, and here’s a few excerpts from my latest pieces in Slate, New Scientist, and Inside Science. (See links below for the full articles.) As usual, thanks go to my insightful editors, Susan Matthews, Lisa Grossman, and Chris Gorski, and thanks to Abigail Malate, who provided illustrations for the light pollution article.


Here’s One Way Trump’s Team Could Manipulate Government Data

It has plans to recalculate the social cost of carbon, which has been called “the most important number you’ve never heard of.”



…Would Trump try to meddle with the government’s data-collection process? His transition team is interested in doing exactly that. One of the first things that might be under attack? A number known as the “social cost of carbon.”

Since 2008, the final year of the Bush administration, agencies like the Environmental Protection Agency, Department of Energy, and Department of Transportation have been required to take the social cost of carbon into account when assessing and enacting regulations. Everything from refrigerators to cars and trucks to power plants emits carbon, which then goes on to hurt our health, our lands, our long-term viability on this planet, etc. The social cost of carbon allows more than 70 federal regulations, and even some local and state ones, to meaningfully and uniformly account for these costs while regulating. It’s sort of like a carbon tax that only applies to government decisions and is never actually paid but still incentivizes long-term good behavior over short-term economic gains.

“It’s the most important number you’ve never heard of,” says Michael Greenstone, a University of Chicago economist.

It exists thanks to a 2007 federal court case that forced the Bush administration to account for the social cost of carbon when regulating the fuel economy of trucks and SUVs. The suit argued, among other things, that the Energy Policy and Conservation Act’s “calculation of the costs and benefits of alternative fuel economy standards assigns zero value to the benefit of carbon dioxide (CO2) emissions reduction” and that these benefits should be included. This was achieved by calculating and accounting for the social cost of carbon. Another court finding upheld and reinforced that decision just last year: A trade association of refrigerator companies had tried to argue that the cost of carbon estimate was just a guess and that the government didn’t have the authority to consider it. The court disagreed, upholding that the calculation “is supported by substantial evidence and is neither arbitrary nor capricious”…

[Read the entire story in Slate, published on 26 January 2017.]

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Trump Transition News in Nature: Budget Situation, Scientists Respond

Here’s a pair of stories I’ve worked on recently on the transition to the Trump era and what that means for science. The second one was written by Heidi Ledford, Sara Reardon and me. Thanks as usual to Lauren Morello for help editing. Thanks also go to my very informative sources. At the end of this post, I’ve also included links to a couple related stories by my Nature colleagues, and I recommend checking them out, too.


Stopgap spending bill leaves US scientists in limbo

Proposal would keep funding flat for most research agencies, but cuts could come early next year.

In what has become a year-end tradition in Washington DC, the US Congress is getting ready to approve a stopgap spending measure before it adjourns for the holidays.

The legislation introduced yesterday in the House of Representatives would hold spending flat at most science agencies, with some limited increases. These include an extra US$872 million to implement provisions of the 21st Century Cures Act, a bill that would reform drug development and biomedical research. The money would be split between the National Institutes of Health, the Food and Drug Administration and state governments…

The stopgap funding bill, which would expire on 28 April, also allows for extra funding to keep a handful of major multiyear space programmes on track. These include the National Oceanic and Atmospheric Administration’s Joint Polar Satellite System, a series of probes designed to monitor Earth’s weather and climate, as well as NASA efforts to explore deep space and develop a replacement for the retired space shuttle.

But for most science programmes, funding would remain at roughly the same level as in the past fiscal year. And continuing to operate under a temporary funding measure means that agencies cannot start new programmes or end old ones without explicit permission from Congress.

“Every time you delay a [final] spending bill, it prevents the science agencies from doing the planning they need, and it keeps them in limbo,” says Lexi Shultz, director of public affairs for the American Geophysical Union in Washington DC…

Many researchers are more worried about what might come after this temporary funding extension, if it is approved. When president-elect Donald Trump takes office on 20 January 2017, Republicans will control the White House and both houses of Congress — and their science priorities are very different from those of outgoing President Barack Obama, a Democrat…

[For more, read the entire story in Nature, published on 7 December 2016.]

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My election polling coverage for Nature

Here’s a few stories I’ve been working on lately for Nature. If you’re interested in them, you can read the whole thing on Nature‘s website. (And if you quote or cite any of them, please give proper credit.) Special thanks go to my editors, Lauren Morello and Richard Monastersky. At the bottom of this, I’ve also posted a few other election-related articles from my colleagues.


Pollsters struggle to explain failures of US presidential forecasts

Most surveys did not predict Donald Trump’s victory over Hillary Clinton.

What went wrong? That’s the question that many political pollsters in the United States are asking themselves in the aftermath of the 8 November presidential election. Republican Donald Trump won in an electoral landslide, but for months most polls forecast a victory for his Democratic opponent, Hillary Clinton.

Many types of polls, including randomized telephone polls and online polls that people opt into, tightened in the weeks leading up to the election — but still pointed to a Clinton win.

“The industry is definitely going to be spending a lot of time doing some soul-searching about what happened and where do we go from here,” says Chris Jackson, head of US public polling at Ipsos, a global market-research and polling firm based in Paris.

(Credit: Reuters/Danny Moloshok)

(Credit: Reuters/Danny Moloshok)

The most recent national polls — including those conducted by ABC/Washington Post, Ipsos, YouGov, and Fox News — all estimated a Clinton lead of 3 to 4% over Trump. Minor-party candidates, such as Gary Johnson of the Liberal Party and Jill Stein of the Green Party, were forecast to win single-digit support. Yet as this article went to press, as the last votes were being counted, Clinton leads the popular vote by a razor-thin margin: just 0.2%. The majority of states have tipped for Trump, awarding him their valuable electoral-college votes and ensuring his victory.

Poll aggregators such as FiveThirtyEight and New York Times nonetheless forecast Clinton’s chances of victory at 71% or higher, while the Huffington Post predicted a Clinton landslide. This dramatic polling failure could have been due to factors such as poorly assessed likely voters, people misreporting their voting intentions, or pollsters poorly surveying some segments of the population.

“It’s a big surprise that such a wide variety of polls using such a wide variety of methodologies have all the errors fall in the same direction,”says Claudia Deane, vice president of research at the Pew Research Center in Washington DC…

[For more, read the entire story in Nature, published on 9 November 2016.]

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News from Nature: Gender Bias in Geoscience, Psychological Disputes, and Mining Asteroids

Here’s a few intriguing and nuanced stories I’ve been working on lately for Nature in Washington, D.C. If you’re interested in them, you can read the whole thing on Nature‘s website. (And if you quote or cite any of them, please give proper credit.) Special thanks go to my editors, Lauren Morello and Jane Lee.


Women postdocs less likely than men to get a glowing reference

Women and men applying for geoscience postdocs receive very different letters of support from their mentors.

Gender bias in scientific fields is no secret, and it is pervasive. It even creeps into the all-important recommendation letter, in which mentors typically bolster the credentials of their protégés.

Globally, female applicants are about 10% less likely than their male counterparts to receive ‘excellent’ letters for postdoctoral positions in the Earth sciences, according to a study published in Nature Geoscience on 3 October. The finding holds regardless of the gender of their recommenders or what part of the world the applicant works in.

“These results uncover a real problem in the geosciences, just like other disciplines,” says Kuheli Dutt, a social scientist at Columbia University in New York City and lead author of the paper. Women start off at a disadvantage, she adds, because they’re perceived as less competent than their male counterparts.

For example, in the US, women in science, technology, engineering and mathematics earn 41% of doctoral degrees, yet in 2012–13 they accounted for only 24% of postdoctoral positions at US federally funded research centres and labs, according to the National Science Foundation. In the geosciences, less than 10% of full professors are women, indicating that the postdoctoral stage — the usual gateway into faculty jobs — is the point at which many women leave the field.

[For more, read the entire story in Nature, published on 3 October 2016.]

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Book review: “Dark Matter and the Dinosaurs” by Lisa Randall

On the one hand, we have the elusive dark matter particles, dispersed throughout the universe across billions of light-years; on the other, we have the sorely missed dinosaurs, who lived in our own proverbial backyard but were driven extinct by a mysterious impactor 66 million years ago. What if these fascinating yet disparate phenomena, separated by so much space and time, were somehow related?


That, in essence, is the premise of Lisa Randall’s book, “Dark Matter and the Dinosaurs.” Maybe the “vanilla” cold dark matter model we have isn’t the only possible explanation of observations of the expanding universe and the cosmic web of millions of surveyed galaxies, she argues. It’s more fun to consider other more exotic models, even if they turn out to be wrong.

Dark matter particles don’t interact with each other the way our familiar atoms do. In fact, they hardly interact at all. They mostly just move apart with the growing universe and then clump together as they feel the effects of gravity over time. As a result, we end up with nearly spherical dark matter clumps throughout the universe, and we and the rest of the Milky Way are living inside one of those clumps. But if some dark matter interacts like normal matter, it could form a dense and thin disk—even thinner than the disk of our own galaxy. (Picture a compact disk hidden inside a bagel. Here’s a good composite image of our galaxy, on edge, which would be the bagel.)

If that’s the case, then as our solar system moves up and down through the disk, we’ll experience an extra little gravitational nudge each time we go through. This could periodically dislodge comets traveling in tenuous orbits in the Oort cloud in the distant realms of our solar system, flinging one comet away forever and sending another in an unfortunate Earthbound direction, where the consequences of its destructive impact in the Yucatan kills off the dinosaurs some 66 million years ago, thus finally linking dinosaurs to dark matter.

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News from Nature: women in physics, atom wranglers, musical preferences

Here’s some fascinating stories I’ve been working on lately for Nature in Washington, D.C. I’m proud of these first three news stories for them, and if you’re interested, check them out on Nature‘s website. (And if you quote or cite any of them, please give proper credit.) Special thanks go to my editors, Lauren Morello and Jane Lee.


Women in physics face big hurdles — still

Persistent biases continue to affect the numbers of female physicists.

There are more women in the sciences than ever before. They hold leading faculty and administrative positions while their representation in fields such as biology, sociology and psychology has increased. Yet the physical sciences are woefully behind when it comes to the number of women at all levels.

“Physics and engineering both have big gender divides,” says Eric Brewe, a physics education researcher at Florida International University in Miami.

This persistent problem prompted a special issue of the journal Physical Review Physics Education Research, with 17 papers and an editorial on gender issues in physics, published on 1 August. Brewe was one of two guest editors for the issue.

(Credit: ullstein bild/Getty)

(Credit: ullstein bild/Getty)

…The special issue addresses the reasons why relatively few women enter the field of physics, as well as the factors that deter them from completing their degrees. They include a lack of role models, entrenched stereotypes and an undervaluing of their abilities. Many authors also highlighted the fact that women are — usually inadvertently — made to feel like they don’t fit in…

[For more, read the entire story in Nature, published on 1 August 2016.]

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Inside Science reviews: “The Big Picture” (Sean Carroll’s book) and “The Man Who Knew Infinity”

Here are excerpts from a new book review and movie review I’ve written recently for Inside Science News Service. I have a few additional thoughts about Sean Carroll’s book, below this excerpt.


Sean Carroll’s ‘Big Picture’ Tours Physics And Philosophy

In a new book, Sean Carroll brings together physics and philosophy while advocating for “poetic naturalism.”

Quantum physics, cosmology, existentialist philosophy and morality may seem like disparate subjects. But Sean Carroll, a theoretical physicist at Caltech, ties them all together into a cohesive and comprehensive worldview he calls “poetic naturalism.” He lays out his views while trying to find meaning in a vast and chaotic universe in his newly published book, “The Big Picture” (Dutton, Penguin Random House Inc.).

Having written two previous popular physics books as well as being active on Twitter and his blog, Carroll takes an interest in communicating complex scientific discoveries. In his new book, he describes some of the fundamental ideas in modern physics with a philosophical lens, while exploring life’s biggest mysteries: the origin of the universe and the meaning of life itself. At the same time, with references to Wile E. Coyote, Captain Kirk and “Bill and Ted’s Excellent Adventure,” he avoids an overly serious tone.

In recent years, prominent scientists like Neil deGrasse Tyson, Bill Nye and Stephen Hawking have downplayed the importance of philosophy or even denigrated it. Carroll is not among this crowd.

“There are a lot of scientists and science promoters who have said not entirely complimentary things about philosophy, but that misses the point about what it’s for,” Carroll said in an interview. “The purpose of philosophy is not to be the handmaiden of science.”

(Credit: Dutton, Penguin Random House, Inc.)

(Credit: Dutton, Penguin Random House, Inc.)

Though his Ph.D. is in physics, Carroll has a strong interest in philosophy as well, and minored in it in college. He sees philosophy as a method for interpreting science and for a deeper understanding of physical phenomena. He uses philosophical concepts such as causality, determinism and mind-body dualism to explore everything from the tiniest subatomic particles to the accelerating expansion of the universe — as well as the role humans play somewhere in between.

For Carroll, naturalism means that there’s one world, the natural world, it obeys the laws of nature, and you can discover it using science. To this he adds that “there are many ways of talking about the world,” stories that people can tell to make sense and meaning of the world and their place in it. He even address issues of free will, consciousness, ethics, and life after death…

…The situation becomes murkier when Carroll discusses quantum mechanics, the interpretation of which has continually generated debates among physicists and philosophers since Max Planck and Albert Einstein discovered light “quanta” in the early 20th century. Physicists interpret quantum systems with probabilities: for example, for a hydrogen atom, the electron doesn’t have a particular position or momentum, but if someone measures them, it has probabilities of being observed in particular states.

Carroll supports the controversial “many-worlds interpretation” in which every quantum possibility is literally a separate world (or universe). We happen to live in one of them, and we have no way of seeing or even confirming the existence of the many unobservable parallel universes. This interpretation seems to conflict with his claim of endorsing a “sparse ontology,” which would mean accepting only a few fundamental concepts for describing the natural world.

“What I took Carroll to be promoting was a kind of ‘verificationism’: what is true is what can be measured,” said Elise Crull, philosopher of science at the City College of New York. “But what counts as ‘measurable,’ and how we distinguish theoretical from observational statements, are complex issues.” This is why, she argues, philosophers considered the view problematic and abandoned it long ago…

[For more, check out the entire story in Inside Science, published on 19 May 2016. Thanks to Chris Gorski and Emily DeMarco for editing assistance.]

Additional thoughts:
I think Carroll’s book does a great job of tying together so many disparate concepts, and I commend his efforts to communicate philosophical ideas. It’s important to encourage people to think and talk about “what it all means.” However, I think Carroll comes across as a little overconfident sometimes, as if he has all the answers. (But he’s more modest at other times.) Furthermore, he’s clearly more of an expert on the physics than the philosophy. His philosophical views don’t seem very nuanced or even self-consistent, and his book lacked a discussion of some important questions. (Exactly what are “laws” of nature and what do they tell us about how things actually behave? How do we assess the simplicity or predictive or explanatory power of a scientific theory?) He also missed some influential philosophers and physicists who have studied “scientific realism” in the context of cosmology and quantum physics for decades.

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Inside Science: Dark Matter Particles, Cosmic Lenses, and Super-Earths

Here’s a few new stories I reported on and wrote for Inside Science News Service over the past couple weeks:


Physicists Look Beyond WIMPs For Dark Matter

Physicists are on the hunt for elusive dark matter, the hypothesized but as yet unidentified stuff that makes up a large majority of the matter in the universe. They had long favored “weakly interacting massive particles,” known as WIMPs, as the most likely dark matter candidate, but after an exhaustive search, some scientists are moving on to more exotic particles.

Most estimates suggest that there’s 5-6 times as much dark matter as there are things that we can see, such as galaxies, stars, and planets. Yet physicists know very little about what the mysterious dark matter particles actually are, as they cannot be directly observed and barely interact with normal matter.

New research leaves dwindling room for WIMPs, motivating a search for other particles that could fit the bill.

“The WIMPs are getting harsh experimental scrutiny, and may get ruled out,” said Kathryn Zurek, a physicist at Lawrence Berkeley National Laboratory in California. [Note: She later clarified that WIMPs may become more “strongly constrained” rather than “ruled out.”]

Physicists have used the Large Hadron Collider's ATLAS experiment to probe for potential dark matter particles. (Credit: CERN)

Physicists have used the Large Hadron Collider’s ATLAS experiment to probe for potential dark matter particles. (Credit: CERN)

Zurek and others presented ongoing work on dark matter alternatives to WIMPs in April at an American Physical Society meeting in Salt Lake City. “We should broaden the searchlight, and the natural place is to go lighter,” Zurek said.

She and her colleagues are looking into less massive particles that interact more weakly with ordinary matter. These include an array of particles with exotic names like “axion,” “sterile neutrino,” and “Higgsino,” a theoretical super-partner of the famous Higgs boson.

Axions are hypothetically abundant particles originally proposed in the 1970s to solve a problem with nuclear physics. In the presence of a powerful magnetic field, these minuscule particles, which are lighter than electrons, are predicted to turn into detectable photons. In spite of years of searching, however, they have yet to be found. But the Axion Dark Matter eXperiment, currently being upgraded, should definitely determine whether the particle exists, said Leslie Rosenberg of the University of Washington in Seattle.

Kevork Abazajian, a cosmologist at the University of California, Irvine, sees a new trend in the field over the past decade. “The new generation of early-career physicists is more open to dark matter other than WIMPs,” he said.

He argued that physicists should consider sterile neutrinos, which interact even more weakly than their neutrino counterparts. As they decay, the particles—which are tinier than electrons—could produce detectable X-ray radiation such as that observed in clusters of galaxies. But scientists struggle to distinguish between X-rays that could be emitted by sterile neutrinos versus traditional astrophysical events. Research along these lines suffered a setback when Japan’s powerful X-ray satellite Hitomi broke into pieces last month. But it may have accumulated limited science data before it was lost…

[For more, check out the entire story in Inside Science, published on 28 April 2016. Thanks to Chris Gorski and Sara Rennekamp for editing assistance.]

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More News from Monterey: Otter Rescue, Coastal Economy, Fog Maps

Here’s a few new stories I reported on and wrote for the Monterey Herald newspaper over the past couple weeks:


Helping otter pups survive El Niño

When a stranded sea otter baby was rescued on Carmel Beach by Monterey Bay Aquarium workers in January, it was a rare enough event to be featured on the television news.

But with more El Niño-strengthened rainstorms returning to the Monterey Bay, these rescues might become more commonplace.

Monterey Bay Aquarium visitors enjoy the sea otter exhibit during the 1:30 feeding at the Monterey Bay Aquarium on Friday. (Vern Fisher - Monterey Herald)

Monterey Bay Aquarium visitors enjoy the sea otter exhibit during the 1:30 feeding at the Monterey Bay Aquarium on Friday. (Vern Fisher – Monterey Herald)

Storms increase the potential for pups to be separated, said Tim Tinker, a biologist for the U.S. Geological Survey and UC Santa Cruz. Otters like to feed closer to shore in shallower water, where the waves are bigger during El Niño. Storms also rip up kelp forests, giving the animals less shelter and resting areas, he added.

Only a few otters have been rescued so far this year, said Andrew Johnson, manager of the aquarium’s Sea Otter Program. “We’re holding our collective breath about the effect of conditions out there.”

Most pups are born between late fall and early spring, and they require many months of nursing and weaning. Adult otters spend much of their time foraging for food, as they need to eat 25 percent of their body weight every day. But an otter mother can’t forage as much and becomes weak by the end of the weaning period.

“She’s on the razor’s edge. It sounds pretty harrowing, but that’s the way they are,” said Tinker. Storms can split up otter pups from their mothers during this particularly vulnerable period. On their own, pups struggle to survive and don’t have much time before they starve or freeze to death.

This is where the aquarium’s sea otter rescue program comes in. Often responding to calls from citizens and networks of volunteers, their staff annually rescue dozens of distressed otters stranded on the shore. Sometimes a pup can be heard before it is seen, chirping or squeaking for its lost mother. In addition to suffering from food limitations, older otters are sometimes found to be sick with disease or injured by white sharks.

When the animals meet certain criteria and respond well to treatment, then the rescue program adopts them. Staff members feed and care for the otters in giant circular tanks, filled with kelp and companions, with plenty of room to swim, play and rest. They pair the pups with a surrogate mother, who helps them grow and learn to survive on their own. After they recuperate, which can take months, the otters are tagged and released back into the wild. “We want them to go out and be a productive member of sea otter society,” said Johnson…

[For more, check out the entire story in the Monterey Herald, published on 5 March 2016. As usual, thanks to David Kellogg for editing assistance and to Vern Fisher and David Royal for their excellent photography.]

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