Month: May 2024

Enlarge / The surface of Ryugu. Image credit: JAXA, University of Tokyo, Kochi University, Rikkyo University, Nagoya University, Chiba Institute of Technology, Meiji University, Aizu University, AIST (credit: JAXA)

An asteroid that has been wandering through space for billions of years is going to have been bombarded by everything from rocks to radiation. Billions of years traveling through interplanetary space increase the odds of colliding with something in the vast emptiness, and at least one of those impacts had enough force to leave the asteroid Ryugu forever changed.

When the Japanese Space Agency’s Hayabusa2 spacecraft touched down on Ryugu, it collected samples from the surface that revealed that particles of magnetite (which is usually magnetic) in the asteroid’s regolith are devoid of magnetism. A team of researchers from Hokkaido University and several other institutions in Japan are now offering an explanation for how this material lost most of its magnetic properties. Their analysis showed that it was caused by at least one high-velocity micrometeoroid collision that broke the magnetite’s chemical structure down so that it was no longer magnetic.

“We surmised that pseudo-magnetite was created [as] the result of space weathering by micrometeoroid impact,” the researchers, led by Hokkaido University professor Yuki Kimura, said in a study recently published in Nature Communications.

Enlarge (credit: Géza Bálint Ujvárosi / EyeEm via Getty)

Ruth Ann Norton used to look forward to seeing the blue flame that danced on the burners of her gas stove. At one time, she says, she would have sworn that preparing meals with the appliance actually made her a better cook.

But then she started learning about the toxic gasses, including carbon monoxide, formaldehyde and other harmful pollutants that are emitted by stoves into the air, even when they’re turned off.

“I’m a person who grew up cooking, and love that blue flame,” said Norton, who leads the environmental advocacy group known as the Green & Healthy Homes Initiative. “But people fear what they don’t know. And what people need to understand really strongly is the subtle and profound impact that this is having—on neurological health, on respiratory health, on reproductive health.”