Astronomers have discovered a rare celestial jewel — a so-called Planetary Nebula (PN) inside a 500 million-year-old Galactic Open Cluster (OC) called M37 (also known as NGC2099). This is a very rare finding of high astrophysical value.
Click here for original story, Discovery of the oldest visible planetary Nebula hosted by a 500-million-year-old Galactic cluster — a rare beauty with a hot blue heart
Source: ScienceDaily