A pair of dwarf stars has been moving closer toward each other. These stars are located deep inside of the Henize 2-428, a planetary nebula. Their collision is expected to eventually result into a catastrophic supernova eruption. The stars are moving at a speed fast enough to circle each other in 4.2 hours, according a publication in the journal Nature.
The merging of two dwarfs will result in a mass approximately twice as heavy as the Sun. They cannot continue cooling when they get such heavy and are expected to compress to a nearly immeasurable pressure levels. The carbon compression at its core will re-start nuclear fusion, leading to a Type Ia supernova.
Surprisingly, the two stars are white dwarfs, which look extremely tiny but with a dense mass as heavy as about 1.8 times of the size of the Sun. The VLT (Very Large Telescope) of the European Southern Observatory in Chile was studying how some of the stars produce asymmetric nebula. Later they focused on Henize 2-248.
Dr. Henri Boffin of the ESO explained that when we looked at this object’s central star, we found not just one but a pair of dwarfs at the core of this glowing, strangely lopsided cloud.
Romano Corradi, a study co-author from the Instituto de Astrofísica de Canarias, said that further observations in the Canary Islands provides us the evidences to determine the orbit of the two stars and estimate the masses of the two stars. This was when the surprising assumptions revealed.
Leveraging the positioning of other telescopes around the world, Boffin and his team of researchers were able to estimate the size of the stars and their possible distance from each other.
Dr. David Jones of ESO noted that the phenomenon would help understand how the merging of two white dwarfs could lead to the formation of supernovae, which was so far purely theoretical.