Image of the butterfly nebula, NGC 6302.
From the dense and dusty Toro that surrounds the hidden star in the center of the nebula to its jets: this is a portrait never before seen from a dynamic and structured planetary nebula.
The James Webb Space Telescope of NASA/ESA/CSA revealed new details of the Nebula Butterfly, NGC 6302. The nebula Butterfly, located about 3400 light years away from the scorpion constellation, is one of the best studied planetary nebulae in our galaxy. This astonishing nebula was previously photographed by the NASA/ESA Hubble Space Telescope. Now the webb has captured a new image of this nebula.
Planetary nebula are among the most beautiful and most elusive “creatures” of the cosmic zoo. These nebulae form when stars with masses between 0.8 and 8 times the mass of the sun lose most of their mass at the end of their lives. The phase of planetary nebula is ephemeral, lasting only about 20,000 years.
Contrary to what the name implies, the planetary nebulae have nothing to do with planets: The confusion of names began several hundred years ago, when astronomers mentioned that these nebulas seemed round, like the planets. The name took, although many planetary nebulars are not round at all – and the butterfly nebula is an excellent example of the fantastic forms these nebulae can assume.
NGC 6302 is a bipolar nebulawhich means that there are two lobes that extend in opposite directions, forming the “wings” of the butterfly. A dark band of dusty gas constitutes the “body” of the butterfly.
This band is actually a Donut -shaped torus that is being seen aside, hiding the central star of the nebula – the old core of a sun -like star that gives the nebula energy and makes it shine. The dusty Donute can be responsible for the insectoid form of the nebula, preventing gas from going out of the star, also in all directions, according to the results in Monthly Notices of The Royal Astronomical Society.
This new image of the webb zoom to the center of the butterfly nebula and to its dusty toro, providing an unprecedented vision of its complex structure. The image uses webb MIDI (Mid-Infred Instrument) data, working in full field unit mode.
This mode combines a camera and a concert to get images in many different wavelengths simultaneously, revealing how the appearance of an object changes with the wavelength. The investigation team complemented Webb observations with Alma (Atacama Large Millimeter/Submillimeter Array) data, a powerful network of radio antennas.
Researchers who analyzed this webb data identified about 200 spectral lines, each of which contains information about the nebula atoms and molecules. These lines reveal nestled and interconnected structures defined by different chemicals.
The investigation team identified the position of the central star of the nebula Butterfly, which warms a cloud of dust previously not detected around them, causing it to shine intensely in the wavelengths of the medium infrared to which Miri is sensitive. The location of the central star of the nebula has remained uncertain so far, because the dust that surrounds it makes it invisible in optical wavelengths.
Previous research to find the star did not have the combination of infrared sensitivity and resolution required to detect the cloud of warm dust that obscures it. With one temperature of 220,000 k, this is one of the hottest central stars known in a planetary nebula of our galaxy.
This burning star engine is responsible for the stunning brightness of the nebula, but its total power can be channeled by the dense dusty gas band around it: Toro. The new webb data show that the Toro is made up of crystalline silicates such as quartz, as well as irregularly dust grains. Dust grains have sizes of the order of a millionth of meter – large, if we consider cosmic dust – indicating that they have been growing for a long time.
Outside the Toro, the emission of different atoms and molecules assumes a structure in various layers. The ions that require the most energy to graduate are concentrated near the center, while those that require less energy are further from the central star. Iron and nickel are particularly interesting, drawing a pair of jets that project out of the star in opposite directions.
Interestingly, the team also detected light emitted by carbon -based molecules known as polycyclic aromatic hydrocarbons, or HAPS. These molecules form flat -shaped flat structures, very similar to honeycomb for shapes found in hives.
On Earth, it is often found Haps in bonfires smoke, car exhaust or burnt toasted bread. Given the location of the HAPS, the investigation team suspects that these molecules form when a “wind bubble” from the central star erupts in the surrounding gas. This can be First evidence of HAPS formation In an oxygen -rich planetary nebula, providing an important glimpse of the details of the formation of these molecules.
