(Left to right): Bo Veisland, MI&I/Science Source; NASA/JPL; Ronaldo Schemidt/AFP/Getty Images

Top stories: A Viking warrior woman, PETA’s targeting of postdocs, and where spacecraft go to die

DNA proves fearsome Viking warrior was a woman

A 10th century Viking unearthed in the 1880s was like a figure from Richard Wagner’s Ride of the Valkyries: an elite warrior buried with a sword, an ax, a spear, arrows, a knife, two shields, and a pair of warhorses. And like a mythical Valkyrie, a new study published late last week found that the warrior was a woman—the first high-status female Viking warrior to be identified.

PETA versus the postdoc: Animal rights group targets young researcher for first time

For decades, the animal rights group People for the Ethical Treatment of Animals (PETA) has focused its efforts on established researchers. But the group has recently launched an aggressive campaign against a postdoc at Yale University studying stress in wild house sparrows who is still near the beginning of her scientific career. PETA insists that the postdoc’s status as an early-career scientist has nothing to do with its campaign, but critics worry that the organization is trying to send a message to all young scientists: Don’t even think about getting into animal research.

Solar system graveyard: Where spacecraft go to die

After 13 years in orbit, NASA’s Cassini spacecraft this morning completed its “death dive” into Saturn’s upper atmosphere. But Cassini is just one of the 42 spacecraft that found their final resting places on other planets. Where did these other robotic explorers go? Who sent them? And how did they die?

Unusual Mexico earthquake may have relieved stress in seismic gap

When a magnitude-8.2 earthquake struck the coast of Mexico’s Chiapas state early this month, the handful of scientists that study the region were stunned, but not altogether surprised. For more than a century, there had been little activity to study—precisely why they thought the area could be due for a big one. Now, they are working to figure out how much, if any, of the 125-kilometer-long Tehuantepec gap along Mexico’s Pacific coast slipped in the quake, which killed more than 90 people and destroyed or severely damaged the homes of 2.3 million more.

Gut microbes could help trigger multiple sclerosis

The trillions of bacteria that live in our intestines, known collectively as the gut microbiome, have been linked to maladies from eye disease to rheumatoid arthritis. Now, two new studies have added another disease: multiple sclerosis, an autoimmune disorder that strips away nerve cells’ protective covers, leading to muscle weakness, blindness, and even death. What’s more, the studies suggest how our gut microbes make the immune system turn against nerve cells—a finding that could lead to treatments, like drugs based on microbial byproducts, that might improve the course of the disease.