During the evolution, process stars will feature different traits. For example, small red dwarfs can continue to generate light for billions of years. Other stars that are larger and brighter may last considerably less before they vanish in the aftermath of supernovae.
In some cases, starts will display intense flaring events during their youth. A team of researchers harnessed the power of the Atacama Large Millimeter/submillimeter Array (also known as ALMA) to learn more about the phenomenon. The results of the study are quite impressive, and they may also solve one of the fascinating astronomical dilemmas.
The researchers focused on FU Orionis stars (FU Ori), with the name being used to designate a type of star and a particular star that can be found in the Orion constellation. This specific star was the first of its kind that was observed during a flaring event in 1937.
Scientists baffled by mysterious binary stars with accretion disks around them
Fu Ori stars are quite young, and they haven’t managed to attract all the required mass; hence they can flare by several orders of magnitude within one year. Previous research has shown that the flaring events can last for several decades, with scientists arguing that the accelerated accretion can cause them during the youth of the star. At the same time, the stars can collect a significant amount of the final mass during the flaring episodes.
Current models suggest that young proto-stars should be less luminous than expected. However, if young stars gather material at a regular rate, they should be brighter. The team surprised when ALMA revealed that FU Orionis features two stars, each with its own accretion disc. There is also a stream of gas that connects the two disks, which appear to be influenced by a flyby.
While it cannot be said that a definite answer has been provided to the luminosity dilemma, the researchers collected valuable data about accretion and flaring. The study was published in a scientific journal.