Scientists have seen evidence of the earliest chemistry in the universe, thanks to telescope measurements on the modified Boeing 747.
After the Great Burial, the universe began to cool, and atoms such as hydrogen, helium, and lithium began to form from free particles. When the whole universe reached a temperature of several thousand degrees, these atoms should begin to associate with each other (otherwise we would not exist), and physics theory suggests that the first bond would be a helium atom bound to a hydrogen atom. But the resulting ion helium hydride has never been found in the universe – so far, thanks to the Stratosphere Observatory for Infrared Astronomy, or SOFIA.
"This was anticipated 30 to 40 years ago in early chemical models,"
the first author of the study, Rolf Güsten from the Institute of Radioastronomy Max Planck, told Gizmodo.
Scientists should first check whether they could even create such a molecule. Researchers have in the 1970s theorized that nearby plasma in planetary mags, dying stars surrounded by dumped material, may contain helium hydride. But scientists have faced challenges in detecting the molecule, questioning whether the molecule exists in space, according to a paper published today in Nature.
"Until recently there was no technology for that," Güsten explained. The signal wavelengths of light that liberates the molecule would absorb the Earth's atmosphere.
Geoffrey Blake, a California Institute of Technology professor who was not involved in the study, told Gizmodo that scientists stopped searching for a molecule in the early universe – meaning a very remote universe – because they could not find it nearby.
But now, NASA and the German Aerospace Center (DLR) have a customized Boeing 747, SOFIA, which was ready to perform a search.
SOFIA is flying at 38,000 to 45,000 feet, according to NASA's list of data, which is more than 99 percent of the infrared radiation absorbing atmospheres. Researchers have put the instrument on SOFIA called the German receiver for astronomy at the Terahertz frequencies (GREAT) and directed it to the planetary NGC 7027, known for providing scientists with a number of other astrochemical discoveries. After three flights in May 2016 and some data analysis, the work revealed the presence of helium hydride molecules in the mags.
These findings showed researchers that the universe could form the molecule itself and improve the understanding of astronomers about the earliest periods after the Great Burst. That's a big deal.
"I would say that this is probably the most important discovery made by the SOFIA Observatory," said Mike Barlow, a professor at University College London, who was not involved in the survey and who reviewed the article. The data are convincing.
So, no, they did not find the exact oldest helium hydride, but now scientists can go back to the search for signatures from further sources, Blake said. It is good to know that the research on the origin of chemistry is going right. It is even cooler for research to take place at one of the least conventional telescopes.