Researchers at the University of Arizona, led by Lucy Ziurys, have discovered organic molecules in planetary nebulae using the ALMA radio telescope complex in Chile’s Atacama Desert.
Planetary nebulae occupy 90% of the interstellar medium. Previously, scientists believed that the matter of planetary nebulae is composed of atoms, but planetary nebulae serve as sources of molecules for the formation of new stars and planets.
At the end of its life, the star loses most of its mass and becomes a white dwarf: during this period, it usually emits strong ultraviolet radiation. It was believed that this radiation destroys any molecules in the interstellar medium, turning them into atoms. Observation results have shown that this is not the case.
During the work, the authors discovered molecular clouds of methanol in distant from the center of the Galaxy: they studied 20 molecular clouds in the Cygnus arms and found methanol in all twenty. They were located at a distance of 13 to 23.5 kiloparsecs from the center of the Galaxy, which is much farther than the outer border of the habitable zone – the region with the most favorable conditions for the origin and safe evolution of life, located within 10 kiloparsecs from the center of the Milky Way.
This tells us that in a dying star, spherical until its last phase, after passing through the planetary nebula stage, there is a very interesting dynamics that changes this spherical shape.
Lucy Ziuris, researchers at the University of Arizona