"In this new composite image, the Chandra data (purple) shows the diffuse X-ray emission and young stars in Cygnus OB2, and infrared data from NASA's now-retired Spitzer Space Telescope (red, green, ...

"If axion clouds, and thereby axions, are discovered, this would be a massive step toward solving the dark matter problem," Noordhuis told Space.com. "The question is: Why are neutron stars the ...