Best Citation Awards

With the click of a mouse, a new mapping tool shows how places in the American West have changed over the last 70 years. With just a Web browser, anyone can open Landscape Explorer , which will pull up a modern Google map of the United States beside a black-and-white aerial image of the western states circa 1950. A slider button allows for scrolling back and forth between past and present. You can type a place or address into the search bar, then zoom in or out. Search for “Lake Powell” and watch the Colorado River’s red rock canyons of the past turn into a reservoir. Type in “Las Vegas” and see Sin City’s sprawling grid of streets disappear into desert arroyos as you swipe back in time. The free tool is an easy way for anyone with an interest in the American West to peruse the past. But Landscape Explorer also has a loftier purpose: helping government agencies, landowners and conservation professionals make complex decisions about how to manage land. The powerful visual contrast b

Doomsday came on May 25 for the payload of a pumpkin-shaped balloon at the edge of space. The floating gourd — inflated with more than 500,000 cubic meters of helium and large enough to fit 60 Goodyear blimps inside it — traversed the southern hemisphere some five times in 40 days, toting a telescope that could see the unseeable. NASA’s Super Pressure Balloon-borne Imaging Telescope, or SuperBIT, was on a mission to probe the cosmos for dark matter , the invisible substance thought to scaffold the universe and bind galaxy clusters together ( SN: 8/8/22, SN: 6/23/23 ). By observing how cosmic structures with strong gravity deflect nearby light, SuperBIT could infer dark matter’s presence. But things had not gone as planned. Early in the mission, satellite communications failed and the telescope’s operators could not retrieve data wirelessly. As SuperBIT made a sixth pass over South America, projections showed the solar-powered telescope heading toward gloomy weather and away from ano

Enormous polygon patterns in rock lie dozens of meters below Mars’ surface, ground-penetrating radar data suggest. Similar patterns develop on the surface in Earth’s polar regions when icy sediments cool and contract. A comparable process long ago may have created the shapes on Mars, found near the planet’s dry equator , researchers report November 23 in Nature Astronomy . If so, the finding hints that the Red Planet’s equator was much wetter and icier, more like a polar region, when the polygons formed 2 billion to 3 billion years ago. “ Buried possible polygons at that depth have yet to be reported” on Mars, says planetary scientist Richard Soare of Dawson College in Montreal, who was not involved in the study. Searching for ancient polygonal terrain on Mars using ground-penetrating radar is a new idea that “could be powerful,” he adds, and could help scientists understand how Mars’ climate has changed in the past. On Earth, polygonal terrain forms in chilly climes when sharp tem

A roughly 2,000-year-old woman with a potentially violent streak has emerged from skeletal rubble found on an island off southwestern England’s coast. A jumble of tooth and bone fragments in a Late Iron Age grave belonged to a young woman who was interred with items that include a sword, shield and bronze mirror, researchers report in the December Journal of Archaeological Science: Reports . The team used a sex-linked protein extracted from tooth enamel to classify the remains as female. The island grave dates to roughly 100 B.C. to 50 B.C., based on radiocarbon dating of a partial bone and the types of metal objects found in the burial. Given tooth wear, the woman died between the ages of 20 and 25. Since the burial’s accidental discovery in 1999 by a farmer plowing a field on England’s Bryher Island, researchers have wondered whether the stone-lined grave contained a man or woman. No other Western European Iron Age grave includes a sword, typically found in male burials from that

The world is in a climate crisis — and in the waning days of what’s likely to be the world’s hottest year on record, a new United Nations report is weighing the ethics of using technological interventions to try to rein in rising global temperatures. “The current speed at which the effects of global warming are increasingly being manifested is giving new life to the discussion on the kinds of climate action best suited to tackle the catastrophic consequences of environmental changes,” the report states. A broad variety of climate engineering interventions are already in development, from strategies that could directly remove carbon dioxide from the atmosphere to efforts to modify incoming radiation from the sun ( SN: 10/6/19; SN: 7/9/21; SN: 8/8/18 ). But “we don’t know the unintended consequences” of many of these technologies, said UNESCO Assistant Director-General Gabriela Ramos at a news conference on November 20 ahead of the report’s release. “There are several areas of grea

To snap up fish, bottlenosed dolphins may rely on more than just sharp sight and sonar detection. The creatures might also pick up on the weak electric pulses prey produce each time their hearts beat or air filters through their gills. In a new experiment, two bottlenosed dolphins named Dolly and Donna reliably sensed faint electric fields on the scale of microvolts , says Tim Hüttner, a sensory biologist formerly affiliated with the University of Rostock in Germany. That puts the marine mammals’ Spidey sense on par with the Guiana dolphin ( Sotalia guianensis ) and some egg-laying mammals like platypuses. The ability to detect the electrical signals living things give off is called electroreception. It has been previously documented in fish, amphibians and sharks (SN: 6/27/16 ). But it was only in 2011 that the Guiana dolphin made the list , as researchers discovered telltale sensory receptors hidden in an organ on the animals’ snouts ( SN : 7 /27/11 ). In 2022, Hüttner and his co