The study of the abundance and reactions of molecules in the Universe, as well as their interactions with radiation, is known as astro chemistry. The field is a mixture of astronomy and chemistry. The study of the abundance and reactions of molecules in the Universe, as well as their interactions with radiation, is known as astrochemistry. The field is a mixture of astronomy and chemistry. While molecular astrophysics is the study of interstellar atoms and molecules and their encounters with radiation. The structure, atomic and chemical composition, evolution, and fate of molecular gas clouds are of particular interest because solar systems are formed from these clouds. The study of how interstellar and circumstellar molecules shape and interact is advancing, for example, by using non-trivial quantum mechanical phenomena in synthesis pathways on interstellar particles. This study may have a major effect on our understanding of the molecules present in the molecular cloud when our solar system formed, which led to the rich carbon chemistry of comets and asteroids, and thus meteorites and interstellar dust particles that fall to Earth by the tons every day. In characterizing the nuclear reactions that occur in stars, as well as the composition of stellar interiors, astrochemistry intersects with astrophysics and nuclear physics. Dredge-up events will occur if a star forms a largely convective shell, carrying the products of nuclear burning to the surface. Expelled material may contain molecules whose rotational and vibrational spectral transitions can be detected with radio and infrared telescopes if the star is losing a lot of mass. Since symmetry-forbidden reactions can only occur on the longest timescales, the sparseness of interstellar and interplanetary space results in some peculiar chemistry. As a consequence, molecules and molecular ions that are unstable on Earth can be contained in large amounts in space.