For the first time, astronomers have discovered the traces of a rare radioactive molecule, a molecule that does not exist on Earth, Phys.org .
The molecule 26-aluminum monofluoride (26AlF) in question is a radioactive isotope of aluminum bound with fluorine atoms and located outside. The limits of our solar system, in the very Vulpecula constellation ("The Little Fox"), about 2000 light-years from our planet.
While scientists have long suspected that this unstable aluminum isotope exists in large quantities in our galaxy ̵
The discovery was made by an international team of astronomers from three continents who published their findings on July 30 in the journal Nature Astronomy
have published spectral signature of these molecules in space, the scientists, who come from the United States, Australia and three European countries, could also observe the active source of the radioactive aluminum isotope – another "incredible first" , after Space. com .
"The first evidence of this kind of radioactive molecule is an important milestone in the exploration of the cool molecular universe," said study author Tomasz Kamiński, astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts
A radioactive molecule is found in the Space discovered – an incredible first! https://t.co/EfzojSDnhS pic.twitter.com/jkh61P8fH0
– SPACE.com (@SPACEdotcom) July 30, 2018
The source of 26Al was traced back to a red nova, known as CK Vulpeculae, or CK Vul – the remainder of a stellar explosion caused by the fusion of two sun-like stars.
The red nova was first seen from the ground nearly 350 years ago and shone brightly over the Englisch: www.mps.mpg.de/en/topics/topic_200603.html Only in 2013, as an astronomer around Kamiński studied with radio telescopes, they could identify the red nova as a kind of star in the sky of the 17th century in Europe. Source of radioactive aluminum isotope.
– Phys.org (@physorg_com) July 30, 2018
According to Space.com a red nova emerges when two low-mass stars collide in an explosive fusion, producing a cosmic burst of light and then cooling and starting to emit large quantities of molecular gas and dust.
In this molecular gas, the debris around CK Vul was that the team detected the signature of the 26AlF radioactive molecule, more than three hundred years after the two stars collided and shredded in a violent explosion.
Kamiński commented on the discovery of a lyrical twist on the celestial event that enabled his team to make an astonishing breakthrough.
"We observe the bowels of a star that was torn apart by a collision three centuries ago How cool is that?"
The observations were made thanks to the Atacama Pathfinder Experimental Telescope (APEX) in the Atacama Desert in Chile and the Northern Extended Millimeter Array (NOEMA) of the Institute of Radio Astronomy Millimetrique (IRAM). Kamiński mentions in a Nature Astronomy commentary that was published alongside the study.
Under normal circumstances, chemical molecules are detected in space after scientists have observed their molecular fingerprints in laboratory experiments, and then search for them using powerful sky telescopes. However, since 26Al can not be found on Earth, the team relied on a more stable aluminum isotope, 27Al, and used the fingerprint of 27AlF molecules to obtain the data needed for the rare 26AlF molecules.
EurekAlert (press release) A pair of colliding stars spill radioactive molecules into space EurekAlert (press release) About 348 years after this event, an international team of astronomers used the Atacama Large Millimeter / Submillimeter Array … https://t.co / qCoVl2Gaaq pic.twitter
– Hurshal (@Hurshal) July 30, 2018
In addition to the discovery of the radioactive aluminum isotope in the red nova, astronomers were also able to give some details about the original two Stars that merged three centuries ago.
For example, they found that one of these low-mass stars was a red giant weighing between 0.8 and 2.5 solar masses. The study also found that star collisions, such as the red nova investigated, can expose and eject space into even the deepest layers of a star where heavy elements and radioactive isotopes are forged.
"This first direct observation of this star The isotope in a stellar-like object is also important in the broader context of galactic chemical evolution," Kamiński said.
Although his team identified a fair amount of 26Al in CK Vul, it is not enough to explain all the radioactive isotopic molecules that are believed to exist in the Milky Way. Therefore, astronomers speculate that there may be other 26Al sources in space waiting to be discovered.
"The observation could be a springboard for the unambiguous identification of other galactic sources of 26Al," the authors write in their paper.