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By Geoff Brumfiel of Nature magazine Contrary to what many students are taught, quantum uncertainty may not always be in the eye of the beholder. A new experiment shows that measuring a quantum system does not necessarily introduce uncertainty. The study overthrows a common classroom explanation of why the quantum world appears so fuzzy, but the fundamental limit to what is knowable at the smallest scales remains unchanged. At the foundation of quantum mechanics is the Heisenberg uncertainty principle....

Scientific American has learned that finance ministers from at least three Western countries are scheduled to meet in Rome next week to announce a pilot program for delivering next-generation vaccines more rapidly to poor nations. An official for the GAVI Alliance, an international vaccines group, confirmed that the project would be the first step of a controversial plan to pay qualifying vaccine makers a higher price than they would ordinarily receive for their products in impoverished areas hard hit by infectious diseases....

Researchers have weighed a planet orbiting a distant star by measuring the starlight passing through its atmosphere. The technique could accelerate the hunt for Earth-like worlds. Knowing the mass of an extrasolar planet, or exoplanet, is an important step in determining whether it is rocky, and thus potentially home to life. To find that mass, astronomers usually rely on radial-velocity measurements, in which tiny wobbles in a star’s orbit reveal the gravitational tug (and hence mass) of an orbiting planet....

(Editor’s note: This article originally appeared in the October 1997 issue of Scientific American magazine. We are posting it because of some related news.) Before Chuck Yeager broke the sound barrier in 1947 in the X-1 experimental plane, engineers had predicted that the buffeting produced by supersonic shock waves might tear apart his sleek craft. As drivers—one might call them pilots—of two custom-made supersonic cars recently prepared to punch through Mach 1, the engineering community voiced similar concerns, perhaps this time with more reason....

SACRAMENTO, California (Reuters) - A moderate dose of winter rainfall hasn’t ended California’s historic drought, but it has dropped just enough moisture on the beleaguered state to help 14 communities that had risked running out of water. In January, public health officials in the most populous U.S. state said that 17 communities were at risk of running out of water in 60 to 90 days. But now just three small communities were at risk, one in the central part of the state and two in the north, Department of Public Health spokeswoman Anita Gore said on Thursday....

In 1994 biologists seeded patches of grassland in Cedar Creek, Minn. Some plots got as many as 16 species of grasses and other plants—and some as few as one. In the first few years plots with eight or more species fared about as well as those with fewer species, suggesting that a complex mix of species—what is known as biodiversity—didn’t affect the amount of a plot’s leaf, blade, stem and root (or biomass, as scientists call it)....

It’s the dreaded part of morning for a dog: watching his or her owner scramble out the door and being left alone for a day of silent waiting. But since the spring of 2020, dogs across the globe who used to longingly stare out the window have suddenly found themselves curled up under the desk by their owners’ feet, hearing the chatter of Zoom calls from above. We gave in to their request for that morning walk—and that midday belly rub, too....

Yet a recent study suggests that at current growth rates, humanity could practically exhaust the most accessible riches in our stellar neighborhood within less than five centuries. To prevent an interplanetary economic crisis, the study’s co-authors suggest that our civilization must somehow build sustainable practices into our expansion out to space, potentially setting aside more than seven eighths of our stellar system’s off-world “real estate” as protected wilderness. The findings appear in the journal Acta Astronautica....

Reviving the moribund US human space-flight program requires shooting not just for the Moon, but also for Mars, says a report released today by the US National Academy of Sciences. It lays out three potential paths to the red planet — while warning that reaching Mars will require NASA to rethink how it plans its missions. Continuing on the agency’s present course “is to invite failure, disillusionment, and the longstanding international perception that human space-flight is something that the United States does best,” the report says....

Kisses are at a premium in the capital of Liberia. Even a hug or a handshake between friends is often out of the question. That’s the new normal ever since Ebola began ravaging communities throughout Liberia, Sierra Leone and Guinea. For much of the past year, residents of these west African countries have wondered if daily life will ever be able to return to the way things once were. And at the heart of the matter is a scientific question: has Ebola now found a permanent foothold among humans?...

Perhaps the only funny item in Jared Diamond’s new book Upheaval: Turning Points for Nations in Crisis is an anecdote about what was known as the Winter War. When the Soviet Union invaded Finland in late 1939, the Finns resisted against the much larger Soviet forces until the two countries compromised on an uneasy peace. Various countries sent equipment to help Finland defend itself. One such gift was World War I artillery from Italy....

In the 1930s French scientists determined that bees could not fly. They knew, of course, that the insects could and did. But according to their calculations, this feat was aerodynamically impossible. They based that conclusion on the fact that wings as small as a bee’s could not possibly produce enough lift to allow the bee to get airborne. The problem was, they presumed that the bee’s wings were stable, like an airplane’s, when in fact honeybees flap and rotate their wings 240 times a second....

In 1915 only 56 years had passed since the publication of Charles Darwin’s On the Origin of Species by Means of Natural Selection. Then, as now, the ramifications of evolution were still being discovered and understood. The study of natural history continued to evolve as a collection of several related sciences, but was generally understood to mean the study of plants and animals and their natural settings. The subset of natural history that studied living human beings had come to be called anthropology....

Scrambling up the steep bank of a small wadi, or gully, near the western shore of Lake Turkana in northern Kenya, I stop on a little knoll that offers a view across the vast, mostly barren desert landscape. The glittering, jade-blue lake contrasts in every way with the red-brown landscape around it. This long, narrow desert sea, nestled within Africa’s Great Rift Valley, owes its existence to the Omo River, whose winding flow delivers runoff that comes from summer monsoon rains in the Ethiopian highlands, hundreds of miles north....

By Ivan Semeniuk , Jeff Tollefson , Meredith Wadman , Adam Mann & Gwyneth Dickey Zakaib On the morning his administration unveiled its budget request for the 2012 fiscal year, US President Barack Obama was addressing students at a school with a specialized science and technology programme in Baltimore, Maryland. The choice was deliberate. Obama has made numerous public appearances in recent weeks to push his strategy of “winning the future” for an embattled US economy by investing in research, innovation and education....

By Alison Abbott of Nature magazineThe increasingly sophisticated blending of different species to create chimeras is pushing biology into a new ethical dimension. Last year, scientists used new stem-cell technologies to create a mouse with a functioning pancreas composed entirely of rat cells. So might it soon be possible to create a monkey with a brain composed entirely of human neurons? And would it think like a human?Such an animal might be useful to researchers studying human cognition or human-specific pathogens....

A mother gives everything to care for her child. Biologists have recently demonstrated the truth of that greeting-card adage at the molecular and cellular levels. It comes as no surprise that the prenatal environment supplies nourishment, hinders embryonic development in the presence of metabolites from smoke or drink–and can even influence which of a child’s genes get turned on or stay silenced. Now French researchers have found that biochemicals from the mother can get involved directly in the development of the embryo and fetus....

Most people assume that their trash ends up in a landfill somewhere far away (if they think about this at all). But growing concern over the environmental impact of waste—discarded electronics, in particular—has prompted a team of researchers at the Massachusetts Institute of Technology (M.I.T.) to take a high-tech approach to studying exactly what people are tossing out and where those items are ending up. The researchers, part of M.I.T.’s Senseable City Lab, have developed electronic tags that they’re hoping as many as 3,000 volunteers in Seattle and New York City will affix to different items they throw away this summer as part of the Trash Track program....

Technology is all around us, expanding the limits of what is possible. but every once in a while, some invention or insight has an outsize effect; it creates a large dis­continuity, dividing history into “before” and “after.” The steam engine, the transistor, the World Wide Web—each of these ideas seemed to emerge from nowhere to change our world in fundamental ways. Which key technology will arise fromtoday’s vast cauldron of innovation to become tomorrow’s world changing idea?...

LEH, INDIA—In the high-altitude desert of the Indian trans-Himalayas, one man is buying time for villagers suffering from global warming by creating artificial glaciers. The ancient kingdom of Ladakh is the highest inhabited region on Earth. Wedged between Pakistan, Afghanistan and China, Ladakh consists entirely of mountains and is home to a mostly Tantric Buddhist population. In the so-called rain shadow of the Himalayas, Ladakh receives just five centimeters of rainwater a year—about the same as the Sahara Desert....