The Stingray Nebula, aka Hen3-1357, appeared for the first time in 1990 when bright nebular lines and radio emission that had not been observed before were unexpectedly discovered (Parthasarathy et al. 1993). In the ensuing years the nebula faded precipitously. We report changes in shape and large decreases in its nebular emission-line fluxes based on well-calibrated images obtained by the Hubble Space Telescope in 1996 and 2016. Hen3-1357 is now a "recombination nebula".
@article{arxiv.2009.01701,
title = {The Decline and Fall of the Youngest Planetary Nebula},
author = {Bruce Balick and Martín A. Guerrero and Gerardo Ramos-Larios},
journal= {arXiv preprint arXiv:2009.01701},
year = {2021}
}