Stingray Nebula (Hen 3-1357)

Hen 3-1357 is a planetary nebula in the southern constellation Ara, and its glowing shape resembles a stingray. It formed from gas shed by a dying central star, so planetary nebula does not mean a planet is present. [NASA](https://science.nasa.gov/missions/hubble/hubble-reveals-details-of-a-newly-born-planetary-nebula/)

NASA described it as the youngest known planetary nebula because astronomers caught its gas becoming ionized and visible on a very short human timescale. Matt Bobrowsky first observed its structure with Hubble in 1993, followed by detailed 1996 and 1997 observations. [NASA](https://science.nasa.gov/missions/hubble/hubble-reveals-details-of-a-newly-born-planetary-nebula/)

Hubble images from 1996 and 2016 show Hen 3-1357 fading and changing shape dramatically over only 20 years. NASA reported that its oxygen emission dropped by nearly a factor of 1,000 between those observations, an unusually rapid change for a nebula. [NASA](https://science.nasa.gov/missions/hubble/hubble-captures-unprecedented-fading-of-stingray-nebula/)

It is not vanishing because it is moving away, but because the gas is no longer being lit as strongly by the evolving central star. NASA's 2020 analysis estimated that at its then-current fading rate it might barely be detectable in 20 or 30 years, so that forecast should be treated as a historical estimate rather than a guaranteed date. [NASA](https://science.nasa.gov/missions/hubble/hubble-captures-unprecedented-fading-of-stingray-nebula/)