An image (NASA, ESA, CSA, STScI, Michael Ressler (NASA-JPL), Dave Jones (IAC)) captured by the James Webb Space Telescope depicts NGC 1514, a planetary nebula with a dying star at its center. The MIRI (Mid-Infrared Instrument) captured details never seen before, especially of the rings visible only in infrared. The dying star has a companion, although in the images, it seems that there’s a single bright star at the center of the nebula. This show will continue for many more millennia before the materials disperse into interstellar space. In the meantime, the dying star already only has a compact core left in the form of a white dwarf.
NGC 1514 has been known since 1790, and the planetary expression reflects the astronomical knowledge of the time. The instruments available to today’s astronomers allowed them to understand the true nature of this type of formation. There’s a star that is going through or has gone through an agony in the form of the ejection of the outer layers of its atmosphere, which generate the nebula. The shows they offer, with a unique geometry for each star, would have astonished William Herschel, the astronomer who observed several planetary nebulae and gave them this name thinking they resembled planets.
About 1,500 light-years away from Earth, the planetary nebula NGC 1514 is peculiar because the dying star has a companion. Due to the amount of material surrounding the pair, examining the two stars has been difficult, to the point that astronomers had originally estimated that they orbit each other in about 10 days, and only observations conducted over the years showed that their orbital period is actually closer to 9 years.
It was only in 2010 that astronomers were able to detect the rings of the planetary nebula NGC 1514 thanks to NASA’s WISE space telescope because they’re so faint that they require instruments very sensitive to infrared. The discovery deserved an article about it, which was published in “The Astronomical Journal” in November of that year.
Those rings are formed by the materials ejected by the dying star and are probably composed of very small grains of dust. The result was compared to an hourglass with the edges cut off. It’s normal for the shapes of planetary nebulae to be irregular due to the chaotic and violent processes that form them, and in this case, there’s also the second star that influences them.
Another unusual feature of the planetary nebula NGC 1514 is the absence of complex carbon molecules. Typically, the elements that mix in planetary nebulae form complex molecules such as polycyclic aromatic hydrocarbons (PAHs). One possibility is that the presence of the second star interfered with the processes that lead to the formation of those molecules. The positive effect for astronomers is that simpler molecules allow more light to pass through, which creates the show of the rings.
The evolution of the planetary nebula NGC 1514 will continue for many millennia. The James Webb Space Telescope has already captured never-before-seen details of this formation, proving once again its power and sensitivity. The images obtained are breathtaking and, at the same time, help astronomers better understand the processes at work during the final phase of the life of many stars.
