Researchers discovered in a new study that a rare type of white dwarf has erupted among the most massive supergiant stars of its kind.
The star in question, called V2487 Oph, is what astronomers call a repeating nova. A rare type of variable star, these objects are white dwarfs, or super-dense dead stars, which sometimes steal material from a nearby star in the binary system. These thefts cause the white dwarf to “come to life” for a short time and appear bright for up to several weeks or even months at a time.
However, in a new study, three astronomers have found that V2487 Oph has a superluminescence or explosion 100,000 times more powerful than any other known explosion, according to a statement.
“The amazing discovery of a supernova from a repeating nova is exciting because it poses a profound astrophysics challenge for astronomers and because of the implications for life in places where it’s not. other in our galaxy,” study author Bradley E. Schaefer, a professor at Louisiana State University, said in the statement.
The team discovered the superlumin on V2487 Oph using archival data from NASA’s planet-hunting Kepler space telescope and confirmed their discovery using publicly available data from the NASA Space Telescope. fleeting Zwicky, a wide-field astronomical survey of the sky.
The team estimates that the energy of just one of the supernovas from the periodic nova is equivalent to about 20 million times the energy of the Carrington Event of 1859, the most intense geomagnetic storm in Earth’s recorded history. again.
“A staggering comparison is that one of the daily super flares on V2487 Oph would be enough to power all of humanity on Earth at a current rate 24 times the age of the universe,” said Schaefer.
Co-author Ashey Pagnotta, a professor at Charleston University in South Carolina, said: ‘These flares occur about once per day, and they appear to have occurred almost continuously from at least 2016 to now”.
Pagnotta added that these super flares “start with a spike in brightness, take about a minute to peak, then fade back to their previous levels. Typical duration of a flare. is about an hour, and at the peak of the flare, the star can be as bright as 2.8 degrees (up to 1.1 on the richter scale).”
So far, supergiants have only been identified in “normal” star types such as “normal” (non-periodic) white dwarfs, giants, supergiant stars and more. This is the first time a supergiant has been detected on a star of the “exotic” type. V2487 Oph is only the tenth known repeat nova in the Milky Way, and the repeat nova remains the rarest class of variable stars.
Kill all possible life
Superstars can occur on any type of star; about 1.6% of stars like our sun produce such outbursts, according to the statement. Due to their extreme nature, superluminescence on a star has the potential to kill off any possible surface life on orbiting planets..
“Super flares will disinfect life on various exoplanet surfaces, destroy all electronic technology, and remove the entire atmosphere from any exoplanet,” the statement noted.
This is a key element in the study of alien planets and the search for evidence of life.
“To take a recent and well-studied case, a supernova was seen coming from Proxima Centauri, the closest star to our sun, which has a planet,” Schaefer said. has a mass approximately one Earth and is in the ‘habitable zone'”. . (The habitable zone is the range of orbital distances over which water can settle on the surface of the world.)
“That is to say, this Earth-like planet is the best-case scenario for finding life, and it’s also the best-case scenario for sending out survey ships and future colonies. But the waves themselves. the supernova will quickly kill all life as we know it, and in fact the supernova will ‘quickly’ tear apart the planet of all its atmospheres, so in this case a planet Earth-like planets around the nearest star, the supergiant prevents the formation of life on any of the planets in the system, and it makes Schaefer added.
While supernovas on V2487 Oph appear to be frequent, as Pagnotta revealed, the star’s last nova event occurred in 1998, fading over several weeks. While studying this unique star, Schaefer conjectured that it is likely that this nova erupts about every 20 years. Given this, the star is “expected to erupt again in any given year,” Schaefer said.
https://www.space.com/superflares-discovered-recurrent-nova-v2487-oph Super-strong superstars discovered erupting from super-dense star bodies