This week, a striking astronomical event could take place in the sky as two stars explode in a huge explosion.
The two-star system, called T Coronae Borealis (or T CrB), is located in the northern hemisphere of the sky, 3,000 light-years away from Earth.
It is currently invisible, but astronomers say it will ignite in a blaze so bright it will be visible to the naked eye for about a week. It is expected to be as bright as the North Star, Polaris.
The galaxy undergoes this dramatic transformation only once every 80 years.
“It’s a unique event that will provide many new astronomers with opportunities,” Rebekah Hounsell, an associate research scientist at NASA’s Goddard Space Flight Center, said in a statement.
Astronomers can’t say for sure when and exactly what time the explosion will occur, but they do predict that the explosion will light up the night sky before the end of the month.
The T CrB star will be visible from Earth at a distance of 3,000 light-years and is expected to shine as brightly as the North Star
To see this cosmic wonder, go outside on a dark, clear night and look northeast.
You want to be as far away from light pollution as possible. If you live in a city, you may have to travel to a rural area to see light pollution.
When T CrB is ignited, it appears in a faint constellation called the Northern Crown or Corona Borealis. It is located in a semicircular region between the constellations Bootes and Hercules.
To help you find this little patch of the night sky, you can start by finding the Big Dipper. Follow the curve of its “handle” until you find a bright, reddish star above the eastern horizon.
That star is called Arcturus. Look straight northeast from there and you should see another bright star called Vega.
Halfway between Arcturus and Vega you will find a faint curl of seven stars. This is the Northern Crown where T CrB will appear.
There is no way to know exactly when T CrB will ignite, so it is best to check several times a week.
The T CrB system consists of a white dwarf—an Earth-sized remnant of a dead star with a mass about that of the Sun—and an old red giant.
The white dwarf star will emit a nova explosion sometime before the end of the month
These two stars are trapped in each other’s gravity. But the red giant is slowly being stripped of its hydrogen by the force of its neighbor.
When the red giant’s hydrogen collects on the white dwarf, pressure and heat are created.
The temperature and pressure on the red giant star increase from about 2,000 to 3,000 degrees Celsius to over 180,000 degrees Celsius. This causes T CrB to eject its outer layers, which accumulate on the surface of the white dwarf planet.
When the red giant’s matter reaches its maximum temperature, a nuclear reaction begins, causing an apocalyptic explosion that releases 10,000 to 100,000 times the annual energy output of the sun.
Such a thermonuclear explosion is called a nova, not to be confused with a supernova. This is the final, enormous explosion that destroys a number of dying stars.
In a nova, the white dwarf remains intact, allowing this event to repeat approximately every 80 years.
The most recent observations of the T CrB nova explosion date back to 1946, 1866. However, records show that the observations were made hundreds of years earlier.
Most nova explosions can last thousands of years, but T CrB is unique in that the entire process is completed in just a week.
When T CrB ignites, its brightness will peak and should be visible to the naked eye for a little less than a week before fading again, which could take as long as 80 years, NASA said.