Science Times: The Kilogram Is Dead. Long Live the Kilogram!

Plus: Ice Age Asteroid Crater Discovered Beneath Greenland Glacier —

View in Browser | Add nytdirect@nytimes.com to your address book. Monday, November 19, 2018 NYTimes.com/Science »

40 Years of Science Times This issue of the Science Times newsletter is arriving in your mailbox a day early, because tomorrow we have a special newsletter for you.  On Nov. 14, 1978, The Times published the first issue of its weekly science section, part of a major redesign and expansion of the newspaper. (The paper's business side wanted a fashion section; A.M. Rosenthal, the executive editor at the time, preferred something more serious, and he prevailed.) Forty years later, we're still here, and this week's section will look at 11 questions for which we'd really like answers (plus others we don't really want answered). It also surveys other topics in science and our world. Look for it in your inbox on Tuesday.  For now, here is this week's wondrous news in science and health.

A one-kilogram sphere of single-crystal silicon, one of the roundest man-made objects in the world. The object helped redefine a kilogram in terms of the number of atoms it contains. Matt Roth for The New York Times The Kilogram Is Dead. Long Live the Kilogram! By XIAOZHI LIM After a vote (and a century of research), the standard measure for mass is redefined, and the long reign of Le Grand K is ended.

Natural History Museum of Denmark/Cryospheric Sciences Lab/ NASA Goddard Space Flight Center Ice Age Asteroid Crater Discovered Beneath Greenland Glacier By NICHOLAS ST. FLEUR It is the first impact crater discovered under one of Earth's ice sheets, according to the scientists who found it. Greek Culture Ministry Rich, Ancient City Is Unearthed in Greece By ILIANA MAGRA Archaeologists unearthed Tenea, which is thought to have been founded by Trojans. They also found tombs, coins and urns, among other items, in and around the city. Illustration by Jules Julien Sigrid Johnson Was Black. A DNA Test Said She Wasn't. By RUTH PADAWER The surge in popularity of services like 23andMe and Ancestry means that more and more people are unearthing long-buried connections and surprises in their ancestry. Gracia Lam Personal Health The Case Against Appendectomies By JANE E. BRODY The appendix is turning out to contain biologically useful tissue that may help prevent nasty gastrointestinal ills.

ADVERTISEMENT

Evan D'Alessandro/University of Miami Hurricane Harvey Passed Over, but These Fish Kept Making Babies By JOANNA KLEIN Underwater audio recordings rescued from Hurricane Harvey showed that the urge to spawn was more powerful than a category 4 storm. Saul Martinez/Getty Images The Psychology of Political Polarization By DANIEL YUDKIN Our country is divided, but science suggests the rift is less severe than it seems. Achmad Ibrahim/Associated Press Why Komodo Dragons Haven't Conquered the World By VERONIQUE GREENWOOD The razor-toothed predators are fierce, but scientists found that they're real homebodies. Illustration by Brian Rea From Gene Editing to A.I., How Will Technology Transform Humanity? By REGINA BARZILAY, GEORGE CHURCH, JENNIFER EGAN, CATHERINE MOHR AND SIDDHARTHA MUKHERJEE Five big thinkers — Regina Barzilay, George Church, Jennifer Egan, Catherine Mohr and Siddhartha Mukherjee — puzzle over the future of the future.

Trump Says California Can Learn From Finland on Fires. Is He Right? By PATRICK KINGSLEY Male Insect Fertility Plummets After Heat Waves By KAREN WEINTRAUB Campi Flegrei Volcano's Ancient Cycle Seems to End in Large Eruption By ROBIN GEORGE ANDREWS Dartmouth Brain Science Professors Are Accused of Sexual Abuse by 7 Women in Lawsuit By ANEMONA HARTOCOLLIS Dorothy Cheney, Who Studied Primates Up Close, Dies at 68 By NEIL GENZLINGER Zhores Medvedev, 93, Dissident Scientist Who Felt Moscow's Boot, Is Dead By ROBERT D. MCFADDEN

GIVE FEEDBACK Let us know what you like and don't like about this newsletter. What do you think about getting two Science Times newsletters in one week? Email us at sciencenewsletter@nytimes.com.

Climate Change Scott Olson/Getty Images 'Like a Terror Movie': How Climate Change Will Cause More Simultaneous Disasters By JOHN SCHWARTZ By the end of this century, some parts of the world could face as many as six climate-related crises at the same time, researchers have concluded. Josh Haner/The New York Times Your Children's Yellowstone Will Be Radically Different By MARGUERITE HOLLOWAY AND JOSH HANER Climate change is altering America's first national park so quickly that plants and animals may not be able to adapt.

We've got more newsletters! You might like Climate Fwd:.   What on Earth is going on? Sign up for the Climate Fwd: newsletter to get our latest stories and insights about climate change — along with answers to your questions and tips on how to help.

Health Joshua Bright for The New York Times The Price of Cool: A Teenager, a Juul and Nicotine Addiction By JAN HOFFMAN E-cigarettes may help tobacco smokers quit. But the alluring devices can swiftly induce a nicotine habit in teenagers who never smoked. This is the tale of one person's struggle. • Q&A: The ABCs of E-Cigarettes Joshua Bright for The New York Times She Couldn't Quit Smoking. Then She Tried Juul. By JAN HOFFMAN Millions embrace e-cigarettes as smoking cessation aids. Will restricting the devices for teenagers put former adult smokers who vape at risk to start again? Illustration by Brian Rea Data-Driven Medicine Will Help People — But Can It Do So Equally? By ZEYNEP TUFEKCI Technological advances threaten to make a crushingly unequal system even more so. Till Lauer There's a Stress Gap Between Men and Women. Here's Why It's Important. By KRISTIN WONG Between domestic duties and emotional labor, research shows, women are more stressed than men are — but it doesn't have to be that way. Here's what the data says, and how to take care of yourself. Stuart Bradford How a Low-Carb Diet Might Help You Maintain a Healthy Weight By ANAHAD O'CONNOR Adults who cut carbohydrates from their diets and replaced them with fat sharply increased their metabolisms. Jeenah Moon for The New York Times Very Brief Workouts Count Toward 150-Minute Goal, New Guidelines Say By GRETCHEN REYNOLDS New federal exercise recommendations include the first-ever federal activity parameters for 3-year-olds, as well as a few surprising omissions. iStock Baby Won't Sleep Through the Night? You're Not Alone By PERRI KLASS, M.D. Parents often feel bad if their babies aren't good sleepers, but a new study suggests there's a lot of variation, even at a year old. Eric Thayer for The New York Times Air Quality in California: Devastating Fires Lead to a New Danger By JULIE TURKEWITZ AND MATT RICHTEL A week after the most destructive fire in state history ripped through this small town, the flames have been replaced by a new danger: the air.

The Fight Against Malaria Has Reached a Standstill By DONALD G. MCNEIL JR. New Peanut Allergy Drug Shows 'Lifesaving' Potential By RONI CARYN RABIN Rapid Cure Approved for Sleeping Sickness, a Horrific Illness By DONALD G. MCNEIL JR. What to Know About Getting a Flu Shot This Year, No Matter Who's Paying By TARA SIEGEL BERNARD

Make a friend's day: Forward this email.  Got this from a friend? Subscribe to the Science Times newletter.

ADVERTISEMENT

FOLLOW SCIENCE FACEBOOK @nytscience Get more NYTimes.com newsletters » | Get unlimited access to NYTimes.com and our NYTimes apps. Subscribe »

ABOUT THIS EMAIL You received this message because you signed up for NYTimes.com's Science Times newsletter. Unsubscribe | Manage Subscriptions | Change Your Email | Privacy Policy | Contact | Advertise Copyright 2018 The New York Times Company 620 Eighth Avenue New York, NY 10018