Tiffany Poon dives with sharks. In fact, it’s one the biggest highlights of her diving year. “As soon as the first one appears, usually in spring, I’ll be at La Jolla Cove spending as much time as possible with them,” Poon says. “Sometimes they’re shy and keep their distance, but often they’ll come by close enough for a nice photograph, and every now and then come in close to eyeball me with my strange camera.” Poon is a citizen scientist for  ...read more

A 3-D image of Mars’ massive volcano, Olympus Mons, which is the largest in the solar system. (Credit: NASA) For millions of years, a group of tiny asteroids circled our solar system. Then, around 9 a.m. on June 28, 1911, one blazed into earthly skies near a village outside Cairo, Egypt. Locals watched the fireball, and they heard its explosion. A farmer even claimed a dog was killed by one meteorite fragment, making it—if true—the only known modern space rock casualty. Let&r ...read more

As galaxy in the Abell 1033 system (in orange at left) travels, it leaves a gas trail behind it that is somehow brighter at the oldest end, near a second white-orange galaxy. (Credit: Francesco de Gasperin/Leiden University) Imagine a sparkler, crackling and spitting, leaving behind a faint trail of smoke. Now imagine your surprise as, instead of dissipating away, that smoke trail actually got bright over time, or lit up. That’s effectively what astronomers have seen in the Abell 10 ...read more

That’s the spot! Thanks to drone technology, this polar bear was spotted getting cozy. (Credit: Intel Corporation) Polar bears’ fortunes deeply tied to the whims of a changing climate, and as the Arctic continues to warm it’s increasingly important to keep an eye on their populations. But the Arctic’s stark white terrain can make that a difficult task to accomplish. In the past, helicopters have been used to spot the bears, but those aircraft are both costly and disturbi ...read more

Wernher von Braun popped briefly back into his office before heading out to a pre-dinner reception. He’d spent the day giving General Bruce Medaris, head of the US Army Ballistic Missile Agency, and Neil McElroy, incoming Secretary of Defense, a tour of the facilities where his team was building America’s first intermediate range ballistic missile. But what von Braun really wanted was to use the same IRBM to launch a small satellite into orbit, ideally before the Soviet Union did the ...read more

(Credit: science photo/Shutterstock) Cancerous tumor cells get addicted to the very drugs meant to eradicate them. It’s an ironic twist in the field of cancer treatment. A small percentage of tumor cells can possess a resistance to cancer-fighting drugs, allowing tumors to return after treatment has stopped. These few cells usually possess a mutation that renders them immune, but the protection comes at a cost. To withstand the drug regimen, the cells must alter their meta ...read more

If you want to impress at a cocktail party, bust this term out. It’s just a fancy word for fat cells, which come in two varieties: brown and white. Brown adipose tissue (BAT), which most animals have, is also called “good” fat because it stores energy as small units that burn easily — think of kindling in a campfire. White adipose tissue (WAT), though, is like a log: It’s harder to burn because it stores energy as one big unit. Our bodies can transform WAT to BAT. U ...read more

Meet the microscale: essentially, a teeny-tiny ruler that’s a must-have for entomologists — researchers who investigate insects. For larger specimens, such as the metallic, wood-boring Chalcophora japonica (or ubatamamushi, as the Japanese call the beetle, pictured at right and below), the device helps measure morphological features, such as genitalia. For smaller species, such as water-dwelling riffle beetles (Optioservus fastiditus, also pictured), the miniature ruler helps measure ...read more

Cosmologists from the U.K., France and Germany have come up with new maps of how dark matter moves throughout the universe. Scientists can’t actually observe dark matter, which makes up about 27 percent of our universe’s total mass, since it doesn’t react to light. So these researchers had to infer its movement by using data from the Sloan Digital Sky Survey (SDSS), an ongoing project to create a 3-D map of the universe. Here, researchers have layered the location of galaxies ( ...read more

A.D. 1728 | Tooth worm, part II: French dentist Pierre Fauchard publishes work that helps dispel the tooth worm myth, at least among dentists. The myth persists in popular lore, however, until the 20th century. A.D. 1847 | Filling the gap: Edwin Truman introduces a natural latex called gutta-percha, made from trees found in Southeast Asia, for use in root canal fillings. Previously, dentists had used anything from silver to lead to asbestos. A.D. 1965 | Laser power: Researchers find that treatme ...read more