When it comes to lithium, modern people are no strangers. Whether smartphones, tablets, drones, electric vehicles, they are powered by lithium batteries. But this modern element is almost as old as the universe, and it is one of the earliest elements in the universe. Recently, Astrophysical Journal express published an important research achievement on ultra lithium rich dwarfs. Based on the medium resolution spectral data of the GuoShouJing telescope (LAMOST), Chinese astronomers have found nine non evolved stars with extremely high lithium content at one time, namely ultra lithium rich dwarfs. The lithium content of one of the super lithium rich dwarfs is 31 times that of the sun, breaking the record of lithium content of such stars. "This research achievement has important scientific significance in revealing the origin and evolution mechanism of lithium in ultra lithium rich dwarfs, and it is also an important discovery made by LAMOST in frontier basic research." On July 6, in an interview with science and technology daily, Shi Jianrong, a researcher at the National Astronomical Observatory of the Chinese Academy of Sciences, stressed. With the big bang 13.8 billion years ago, lithium appeared within 20 minutes of the birth of the universe. As one of the basic elements of the universe, lithium is the key element connecting the big bang, interstellar matter and stars. The evolution of lithium in the universe and stars has always been an important topic in the field of astronomy. "However, the understanding of lithium in contemporary astronomy still has great limitations." Shi Jianrong said frankly. In the past, astronomers have found that there is an abnormally high content of lithium in a very small number of stars that have evolved. These stars are called lithium rich giant stars. In the past few years, LAMOST has made a series of breakthroughs in the research of lithium rich giant stars, and has found more than 10000 lithium rich giant stars, which has deepened human understanding of such rare objects and the evolution of lithium in giant stars. The existence of lithium rich giant stars shows that there is an unknown mechanism in the evolution of stars, which can significantly change the lithium content on the surface of stars. However, the newly discovered nine strange lithium rich dwarfs show that not only giant stars, but also a very small number of dwarfs that have not yet evolved also show an abnormally high lithium content. "The lithium content of these nine lithium rich dwarfs is at least three times higher than that of the sun, which means that these stars may have formed in an environment with higher lithium content than that near the sun, or some special mechanism has increased the lithium content on the surface of these stars." Shi Jianrong explained. In fact, such lithium rich dwarfs that have not yet evolved into giant stars are very rare. In the past, astronomers found only four stars, so little is known about their formation mechanism. The formation mechanism of lithium rich dwarfs has always been controversial. "Astronomers believe that atomic diffusion, the accretion of lithium rich material around stars, and the interaction between stars and companion stars in binary systems may lead to the abnormally high lithium content of ultra lithium rich dwarfs." Shi Jianrong said. Through in-depth analysis of the nine newly discovered ultra lithium rich dwarfs, researchers found that for most of the ultra lithium rich dwarfs, the accretion of surrounding lithium rich materials may be the main mechanism for their abnormal increase in lithium content, but it does not rule out that a few ultra lithium rich dwarfs are the result of binary star interaction. (Xinhua News Agency)