ESO has published a new image of the planetary nebula ESO 577-24 captured by its Very Large Telescope (VLT) in Chile thanks to its FORS2 instrument, which for almost twenty years has been capturing some of the best astronomical images obtained by the VLT. ESO 577-24 represents the final phase of the life of the star at its center, cataloged as Abell 36, in astronomical terms an instant of agony since its duration is estimated around 10,000 Earth years.
The term planetary nebula is the result of an error of interpretation by astronomers who had limited tools available and mistooke them for formations similar to the solar system’s gas planets. Actually, they represent a phase that’s short from the astronomical point of view of the life of a star of mass similar to the Sun when it becomes a red giant and its outer layers get ejected.
Approximately 1,400 light years from Earth, the planetary nebula ESO 577-24, also known as IRAS F13378-1937 or 2MASS J13404134-1952553, was discovered in the 1950s during the National Geographic Society – Palomar Observatory Sky Survey. The central star went through its red giant phase and ejected its outer layers, but now the remaining core can no longer sustain nuclear fusion, so it’s contracting into a volume that will eventually be comparable to the Earth’s. It will become a white dwarf and at the moment it’s extremely hot, so it emits ultraviolets that ionize the materials that surround it and make them shine.
Because of that agony, the ejected materials are moving away from the central star, which will gradually cool down after reaching a new stability. All this will also cause a decrease in the ionization of the materials, with the consequence that their brightness will slowly fade away until it disappears. These are the reasons why a planetary nebula has a duration limited to few millennia and ESO 577-24 may already be close to its end in astronomical terms.
The image (ESO) shows the planetary nebula ESO 577-24 photographed by the FORS2 (FOcal Reducer and low dispersion Spectrograph) instrument, with the central star Abell 36 visible in white while the red and blue parts show the optical frequency emissions of those colors. In the image you can see a sort of cosmic photobombing because a passing asteroid left a trace in the lower left corner of the star. Several galaxies are visible behind ESO 577-24.
The images generated by the various ESO instruments during the observations are collected in an archive that can be useful for future research. In some cases the VLT can’t be used for scientific research, in these cases the Cosmic Gems Programme allows to produce images that can be interesting for educational use and attract attention even if just for aesthetic reasons. Many astronomical images are both spectacular and useful from a scientific point of view, initiatives to spread them can capture the public’s attention and generate interest in astronomy. This image of the planetary nebula ESO 577-24 perfectly matches this description.