Using NASA’s Chandra Telescope, astronomers have discovered for the first time evidence of a rare white dwarf supernova near the core of our Milky Way galaxy.
Supernovae come in various shapes and sizes but are widely considered “the largest fireworks” in the universe.
X-ray: NASA / CXC / Nanjing Univ./P. Zhou et al. Radio: NSF / NRAO / VLA
Astronomers originally classified these supernovae as either a type 1 supernova or a type 2 supernova, although today we know that there are many species that have their own quirks. One of these classifications is a type Ia supernova, which originates from a white dwarf, the hot core of a star that has shed its outer layers, where it is torn apart by a runaway thermonuclear reaction resulting from the star’s merging or the withdrawal of a lot of material from its neighbor.
Until recently, the remnants of a Type Ia explosion were thought to have been found near the core of the Milky Way, a supermassive black hole dubbed Sagittarius A *.
Astronomers have called the object near Rami A * area “Sgr East A”.
But data from NASA’s Chandra X-ray Space Telescope challenged that classification, and instead indicated that astronomers had found something even rarer.
Instead of being torn apart by a rapid thermonuclear reaction, this white dwarf was destroyed by an unknown process.
Astronomers from the United States, China and the Netherlands believe they have found evidence of an Iax supernova.
These species do not always kill the star, and according to a 2014 study by the Space Telescope Science Institute (STScI), they may leave behind a “Zombie star”.
One theory suggests that Iax supernovae are caused by thermonuclear reactions that travel more slowly.
The resulting eruptions are thus much weaker and can leave part of the star behind.
In other galaxies, these supernovae account for a third of the repeating type Ia supernovae.
Scientists say that the really amazing thing about this new discovery “is that we have never seen evidence of such a supernova in our galaxy.”
“While we have found Iax supernovae in other galaxies, we have not identified evidence of one of them in the Milky Way galaxy yet. This discovery is important for identifying the many ways in which white dwarves explode,” said Ping Zuo of Nanjing University.
And the explosive death of white dwarves is an important source of heavy elements throughout the universe. And when it erupted, it released iron, nickel and chromium into space, effectively feeding space with the elements that make up planets and life.
And just like the massive nuclear furnace, the stars are the only place where these elements can form.
“This finding shows us the types and causes of white dwarf explosions, and the different ways in which these basic elements are made,” said study co-author Cheng Zhi Leung of the California Institute of Technology in Pasadena. The closest known example to Earth. “
The team using the Chandra data was able to identify the object over a period of 35 days by detecting unusual X-ray signals from this region of the Milky Way.
The results are supported by computer simulations that predict a white dwarf torn by a slow-moving thermonuclear reaction.
“The supernova remnant is in the background of many Chandra images of the supermassive black hole of our galaxy that were taken over the past 20 years,” said Jiuan Li of Nanjing University. “We may have finally come to terms with what this object is and how it became.”