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Aisha, Miriam and Akhi are three young factory workers in Dhaka, the capital of Bangladesh. They are poorly educated and badly paid. But, like millions of other young women, they relish their freedom from the stultifying conformity of rural life, where women are at the constant beck and call of fathers, brothers and husbands. There is something else. The three women together have 22 siblings. But Aisha plans three children, Miriam two and Akhi just one....

QUITO, May 25 (Reuters) - A volcano perched atop one of Ecuador’s Galapagos Islands erupted in the early hours of Monday, the local authorities said, potentially threatening a unique species of pink iguanas. The roughly 1.7-kilometer (1.1-mile) high Wolf volcano is located on Isabela Island, home to a rich variety of flora and fauna typical of the archipelago that helped inspire Charles Darwin’s theory of evolution following his 1835 visit. “The Wolf volcano is not located near a populated area....

Nearly 100 years ago Edwin Hubble discovered that the universe is expanding: almost all galaxies are speeding away from our own Milky Way, and faraway galaxies are receding faster. That discovery was profound, but it was followed, in 1998, by an even more startling realization: the expansion is accelerating. For most of the 20th century, scientists had expected that over time gravity would pull galaxies toward one another, slowing the expansion....

Key concepts Electricity Magnetism Gravity From National Science Education Standards: Light, heat, electricity and magnetism Introduction Have you ever noticed your hair standing out on a dry day, or how a fuzzy fleece blanket can make sparks if you rub two sections of the blanket together in the dark? Both of these things are caused by electricity—which also runs as current through wires behind light switches and electrical outlets. But the form of electricity that causes hair to stand up, known as static electricity, is much weaker (though strong enough that a buildup of static electricity can cause a slightly painful shock if you touch the right surface)....

Plain white office paper could be the basis for efficient batteries. Scientists have converted sheets of them into efficient electrical storage devices using ink loaded with carbon nanotubes. This new spin on an ancient invention is the latest in a line of research striving to incorporate paper into batteries to reduce their weight, one of battery technology’s major shortcomings. To trim weight, researchers have tried several approaches, including the use of thin films of materials laid down as inks....

Coral reefs are the backbone of marine life. Now, these rainbow-hued constructions of millions of tiny polyps are being bleached bone-white by pollution and climate change, among other causes. The exquisitely sensitive creatures that make up the reefs live in symbiosis with algae, which give the reefs their color and the polyps their food. But when ocean temperatures rise too high, the corals must expel their algae and, when their stores of food energy run out, die....

Nanotech systems based on DNA may be on the verge of becoming very large and complex, if not immediately useful to medicine or manufacturing. Researchers have combined simple strands of DNA into the most elaborate logic circuits yet, with potential for even more growth, the creators say. Another group has turned DNA chains into a rudimentary robotic system, namely a grid containing dozens of flipperlike arms. Both systems get by on nothing more than the zipping and unzipping of complementary DNA sequences....

Call it the end of an era. Harold Varmus, director of the US National Cancer Institute (NCI) and former director of the National Institutes of Health (NIH), announced on March 4 that he will be stepping down from his post at the end of the month. Varmus is leaving the institute with few regrets. “I got the big things I wanted to start in motion,” he says. This includes expanding research on cancer genomics and changing how investigators are funded in an environment in which grant money has been tight....

Over the past decade Iran has been cautiously, but steadily, putting in place all the elements it needs to construct a nuclear weapon in short order. But as James R. Clapper, director of National Intelligence, told the U.S. Senate in January, while the Iranians are “moving on that path … we don’t believe they have actually made the decision to go ahead with a nuclear weapon.” For several years experts have debated the possibility of a “breakout” scenario in which Iran makes a mad dash to complete and test its first bomb before other nations can act to stop it....

When I first heard the reports of a “mysterious pneumonia” spreading in Wuhan, China, in January 2020, I thought I would write a story or two about it and move on to the next big medical news development. As a health journalist, disease outbreaks are not a rare occurrence on my beat, and most do not rise to the level of an international emergency. But the story of COVID-19 would turn out to be unlike anything I had covered before or am likely—I hope—to ever cover again....

By Virginia Gewin of Nature magazine More than 275 million people have moderate-to-profound hearing loss, and many of those cases are caused by a breach in the connection between the inner ear and the brain. Researchers have now shown how to repair a key component of that connection — the auditory nerve — by using human embryonic stem cells to restore hearing in gerbils. “We have the proof of concept that we can use human embryonic stem cells to repair the damaged ear,” says lead author Marcelo Rivolta, a stem-cell biologist at the University of Sheffield, UK, whose research appears in Nature today....

A ball of string tied into countless knots could very well be seen as a source of frustration. But for the ancient Inca civilization, carefully tied knots formed the basis of a method of recordkeeping known as khipus. Now researchers report that the ledger system is more complex than previously believed and includes a way of communicating information to higher-ups in the well-categorized Incan chain of command between workers and administrators with higher rank....

Six months after the birth of her second child, Patricia, a woman with an active and fulfilling sex life, found herself unable to achieve orgasm. “My partner and I tried everything,” she says. “And it was so frustrating because I’d almost reach climax, time and time again, and then … nothing.” After a few months, her frustration led her to visit a local clinic for sexual disorders. “They brought in a social worker who asked me a lot of questions about abuse....

Working late in the developmental biology lab one night, Matthew Harris of the University of Wisconsin noticed that the beak of a mutant chicken embryo he was examining had fallen off. Upon closer examination of the snubbed beak, he found tiny bumps and protuberances along its edge that looked like teeth–alligator teeth to be specific. The accidental discovery revealed that chickens retain the ability to grow teeth, even though birds lost this feature long ago....

Don’t be fooled by the innocuous name—Curiosity, NASA’s new Mars rover, is a brute. Curiosity, which is slated to launch Saturday morning on an Atlas 5 rocket from Cape Canaveral Air Force Station in Florida, is the biggest planetary rover ever built. The six-wheel-drive robot is three meters long—longer than a Smart ForTwo mini car—and its headlike mast rises 2.1 meters above the ground. With a suite of 10 science instruments, Curiosity weighs in at nearly 900 kilograms, more than NASA’s last three Mars rovers combined....

When a star the size of 20 suns dies, it becomes, in the words of astrophysicist Zaven Arzoumanian, “the most outrageous object that most people have never heard of”—a city-size body of improbable density known as a neutron star. A chunk of neutron star the size of a Ping-Pong ball would weigh more than a billion metric tons. Below the star’s surface, under the crush of gravity, protons and electrons melt into one another to form a bulk of mostly neutrons—hence the name....

TALES OF ENTANGLEMENT “Spooky Action,” by Ronald Hanson and Krister Shalm, discusses quantum entanglement, in which two particles exhibit a “spooky” connection regardless of distance. The authors do not explain why something as nonspooky as the following can’t be going on: Suppose I hide a pair of gloves in two different envelopes and send one (without knowing which) to my friend on Mars, with a note to open it on receipt....

Parasites give new meaning to the cliché “eat or be eaten.” Often their life cycle can be completed only if they are ingested by a host—multiple times for some—making the odds of their survival seemingly minuscule. To improve their chances, certain parasites manipulate their hosts’ behavior to make it more likely the eater will get eaten. The parasitic cestode Schistocephalus solidus requires a much larger host—specifically, a three-spined stickleback fish—to grow in and then a bird to breed in....

From Nature magazine A trio of researchers has encoded a draft of a whole book into DNA. The 5.27-megabit tome contains 53,246 words, 11 JPG image files and a JavaScript program, making it the largest piece of non-biological data ever stored in this way. DNA has the potential to store huge amounts of information. In theory, two bits of data can be incorporated per nucleotide — the single base unit of a DNA string — so each gram of the double-stranded molecule could store 455 exabytes of data (1 exabyte is 1018 bytes)....

Editor’s Note: This story was originally printed in the February 2004 issue of Scientific American. We are reposting this story because author Adam Riess was selected as a MacArthur Fellow in 2008 by the MacArthur Foundation. From the time of Isaac Newton to the late 1990s, the defining feature of gravity was its attractive nature. Gravity keeps us grounded. It slows the ascent of baseballs and holds the moon in orbit around the earth....