- Jul 29, 2021
The universe is incredibly huge and filled with horrific black holes that can tear the planets apart. However, in the moments immediately following the Big Bang, the universe was a rather dull and empty place filled only with hydrogen and helium atoms. Scientists believe that hydrogen and helium collided – forming the very first molecule the universe has ever seen.
For the first time, the NASA Infrared Astronomy Stratospheric Observatory (SOFIA) discovered the very first molecule in space — helium hydride. The discovery was made after studying the planetary nebula NGC 7027, a cloud of gas and dust escaping from a dying star at a distance of about 3000 light years from Earth.
The discovery of a molecule hiding in the solar system is an important step in confirming hypotheses about the ancient universe and the interactions that occurred after the Big Bang. The results were published in the journal Nature on Wednesday.
Astrophysical models predicted that the best place to search for HeH + are planetary nebulae, that is, extended gaseous shells, dropped by stars like the Sun in the process of becoming a white dwarf. In this case, the intense radiation of a hot compact star will ionize all the matter in the vicinity, which creates favorable conditions for the long existence of helium hydride, which otherwise would immediately react with any molecule or atom. It was there that the compound was found – in the planetary nebula NGC 7027.
“The discovery of HeH + is a thrilling and beautiful demonstration of nature’s desire to form molecules,” says co-author David Neufeld of Johns Hopkins University.
Despite the less promising ingredients available — a mixture of hydrogen and inert noble gas of helium — and an aggressive environment with temperatures of thousands of degrees, a fragile molecule still forms. It is worth noting that this phenomenon can not only be observed by astronomical methods but also understood using theoretical models
The discovered compound is not a relic of the Big Bang but re-formed under suitable conditions in the modern universe. However, its registration indicates a correct understanding of space chemistry, including early eras. In the future, the authors intend to use more sensitive devices, such as an array of ALMA antennas, to search for the signal of this molecule in distant galaxies of the early universe.