One-millionth level of divinity, lasting only a few hours… Star Explosion Type Zoom
A star with a luminosity of thousands or tens of thousands of times within a few days is called a ‘nova’.
In the last stage of stellar evolution, the energy generated by the explosion of a star is momentarily released and the brightness becomes brighter, so it is named as if a new star was formed.
A ‘supernova’ or ‘supernova’ is called a ‘supernova’ or ‘supernova’ when it is thousands or tens of thousands of times brighter than such a nova.
However, in contrast to supernovae, a new stellar explosion phenomenon called ‘micronova’, which has much less energy than a nova, has been identified and reported in the academic world for the first time.
According to the European Southern Observatory (ESO), a research team led by astronomer Dr Simon Scaringe of Durham University in the UK has conducted NASA’s astronomical transit exoplanet exploration satellite ‘TESS’ and the ESO Supergiant Telescope (VLT). The results of finding the micronova were published in the scientific journal ‘Nature’.
Although dubbed ‘micro’, it is suggested that they release a tremendous amount of energy capable of burning the material equivalent to 3.5 billion of the Great Pyramid of Giza, Egypt, weighing 20 million tera (T), for example, about 5.9 billion kilograms, in a matter of hours. .
Like nova, Micronova has been observed in a white dwarf, a dead star similar to Earth’s, with half the mass of the Sun but the same size.
A white dwarf in a binary system absorbs material such as hydrogen mainly from a nearby companion (stellar partner), and hydrogen atoms are fused to helium.
These explosions ignite the surface of the white dwarf, glowing brightly for weeks.
Micronova goes through a similar process, but the explosion is small and fast, so it lasts only a few hours.
Among white dwarfs, it occurs in stars that have a strong magnetic field and send matter to the magnetic pole.
It is said that hydrogen fuel sucked from a companion star is focused on the stimulus of a white dwarf, and hydrogen fusion takes place only here, and an explosion that is only one millionth of a nova occurs.
The research team discovered three short explosions by chance while analyzing the TESS data.
Of these, two were captured from a location identified as a white dwarf, and the other was confirmed to be a white dwarf through additional observation using the X-shooter, a spectrometer mounted on the VLT.
The research team predicts that the discovery of micronovas will broaden the types of star explosions and will lead to the discovery of more micronovas.
“These results show how dynamic the universe is,” said Dr. Scaringe, the first author of the paper.
/yunhap news