20 Years of Hubble Photos Show how the Stingray Nebula is Fading

The Stingray Nebula is the youngest known planetary nebula. For half a century astronomers have witnessed its formation, and now they’ve noticed something strange: it’s fading away. "This is very, very dramatic, and very weird," said Martín A. Guerrero of the Instituto de Astrofísica de Andalucía in Granada, Spain, one of the co-authors of a …